The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake were investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria （DPB） sludge. The lab-scale experiments...The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake were investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria （DPB） sludge. The lab-scale experiments were accomplished under conditions of various nitrite concentrations （5.5, 9.5, and 15 mg/L） and mixed liquor suspended solids （MLSS） （1844, 3231, and 6730 mg/L）. The results obtained confirmed that nitrite, MLSS, and pH were key factors, which had a significant impact on anaerobic phosphorus release and anoxic phosphorus uptake in the biological phosphorous removal process. The nitrites were able to successfully act as electron acceptors for phosphorous uptake at a limited concentration between 5.5 and 9.5 mg/L. The denitrification and dephosphorous were inhibited when the nitrite concentration reached 15 mg/L. This observation indicated that the nitrite would not inhibit phosphorus uptake before it exceeded a threshold concentration. It was assumed that an increase of MLSS concentration from 1844 mg/L to 6730 mg/L led to the increase of denitrification and anoxic P-uptake rate. On the contrary, the average P-uptake/N denitrifying reduced from 2.10 to 1.57 mg PO4^3--P/mg NO3^--N. Therefore, it could be concluded that increasing MLSS of the DEPHANOX system might shorten the reaction time of phosphorus release and anoxic phosphorus uptake. However, excessive MLSS might reduce the specific denitrifying rate. Meanwhile, a rapid pH increase occurred at the beginning of the anoxic conditions as a result of denitrification and anoxic phosphate uptake. Anaerobic P release rate increased with an increase in pH. Moreover, when pH exceeded a relatively high value of 8.0, the dissolved P concentration decreased in the liquid phase, because of chemical precipitation. This observation suggested that pH should be strictly controlled below 8.0 to avoid chemical precipitation if the biological denitrifying phosphorus removal capability is to be studied accurately.展开更多
The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH4-, NO3-...The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH4-, NO3-, NO2- as well as the total dissolved inorganic nitrogen （DIN）. The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 ~mol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and could easily lead to phytoplankton blooms in nature if discarded with no treatment. The de-eutrophication abilities of U. pertusa varied greatly and depended mainly on the original eutrophic level the U. pertusa material was derived from. U. pertusa used to living in low DIN conditions had poor DIN removal abilities, while materials cultured in DIN-enriched seawater showed strong de-eutrophication abilities. In other words, the de-eutrophication ability of U. pertusa was evidently induced by high DIN levels. The de-eutrophication capacity of U. pertusa seemed to also be light dependent, because it was weaker in darkness than under illumination. However, no further improvement in the de-eutrophication capacity of U. pertusa was observed once the light intensity exceeded 300 pmolM2 S1. Results of semi-continuous wastewater replacement experiments showed that U. pertusa permanently absorbed nutrients from eutrophicated wastewater at a mean rate of 299 mg/kg fresh weight per day （126 mg/kg DIN during the night, 173 mg/kg in daytime）. Based on the above results, engineered de-eutrophication of wastewater by using a U. pertusa filter system seems feasible. The algal quantity required to purify all the eutrophicated outflow wastewater from the Qingdao Yihai Hatchery Center into oligotrophic level I dean seawater was also estimated using the daily discharged wastewater, the average DIN concentration released and the de-eutrophication capacity of U. pertusa.展开更多
Non-specific lipid transfer proteins(nsLTPs) are small, basic proteins that are characterized by an eight-cysteine motif. The biological functions of these proteins have been reported to involve plant reproduction and...Non-specific lipid transfer proteins(nsLTPs) are small, basic proteins that are characterized by an eight-cysteine motif. The biological functions of these proteins have been reported to involve plant reproduction and biotic or abiotic stress response. With the completion of the barley genome sequence, a genome-wide analysis of nsLTPs in barley(Hordeum vulgare L.)(HvLTPs) will be helpful for understanding the function of nsLTPs in plants. We performed a genome-wide analysis of the nsLTP gene family in barley and identified 70 nsLTP genes,which can be divided into five types(1, 2, C, D, and G). Each type of nsLTPs shares similar exon and intron gene structures. Expression analysis showed that barley nsLTPs have diverse expression patterns, revealing their various roles. Our results shed light on the phylogenetic relationships and potential functions of barley nsLTPs and will be useful for future studies of barley development and molecular breeding.展开更多
In order to</span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> study the meat quality characteristics of </span>...In order to</span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> study the meat quality characteristics of </span><span style="font-family:Verdana;">Ningdu</span><span style="font-family:Verdana;"> yellow rooster, the 7 indexes of 120 healthy </span><span style="font-family:Verdana;">Ningdu</span><span style="font-family:Verdana;"> yellow rooster</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> after </span><span style="font-family:Verdana;">slaughter</span><span style="font-family:Verdana;"> at the age of 16 weeks were determined, and correlation analysis, regression analysis </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> principal component analysis were carried out among the indexes.</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The results showed that the variation coefficient of PH value was smaller than that of water drop rate and meat colorimetric, and the lactic acid produced by anaerobic glycolysis of glycogen in chicken meat was slower.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Through correlation analysis, the 24-hour drip rate was strongly correlated with the 48-hour drip rate (coefficient ≥</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.7,</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">p</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">≤</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.05), and the other indicators were independent of each other.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">By means of</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> regression analysis, the regression equation (fitting degree R</span><sup><span style="font-family:Verdana;">2</span></sup></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">=</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">0.984) of </span><span style="font-family:Verdana;">24</span><span style="font-family:Verdana;">- and 48-hour drip rate was established.</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Principal component analysis synthesized 7 indicators into 3 principal components, with a cumulative contribution rate of 70.13%, indicating that the meat quality of Ningdu Yellow chicken rooster is mainly selected by water drop rate, PH value </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> meat color test.展开更多
Wheat is one of the most important staple crops worldwide.Fusarium head blight severely reduces wheat yield and quality.Cultivation of a novel type of cleistogamous wheat mutant,ZK001,which was created by static magne...Wheat is one of the most important staple crops worldwide.Fusarium head blight severely reduces wheat yield and quality.Cultivation of a novel type of cleistogamous wheat mutant,ZK001,which was created by static magnetic field treatment,is a new strategy for controlling Fusarium head blight.However,little is known about the mechanism of cleistogamy in wheat.The present study demonstrated that anthers of ZK001 were retained on the glumes at all flowering stages,whereas those of YM18 were extruded from the paleae and lemmae.There was a clear difference in the morphological characteristics of lodicules between YM18 and ZK001.Lodicule calcium and potassium contents were significantly higher in YM18 than in ZK001 from white to yellow anther stages.In Fusarium head blight resistance,the diseased kernel rate and deoxynivalenol content of ZK001 were markedly lower than those of YM18 and QM725.Comparative transcriptome analysis of YM18 and ZK001 was performed to identify regulatory mechanisms of cleistogamy.The main differentially expressed genes identified in the spikelets of YM18 and ZK001 at the green anther stage were associated with cell walls,carbohydrates,phytohormones,water channel,and ion binding,transport,and homeostasis.These differentially expressed genes may play an important role in regulating cellular homeostasis,osmotic pressure,and lodicule development.The results indicate that ZK001 lost the ability to push the lemmae and paleae apart during the flowering stage because of the thin lodicules.ZK001 was speculated to provide structural barriers for Fusarium head blight during the flowering stage.The thin lodicule of ZK001 results from low levels of soluble sugar,calcium ions,and potassium ions in the lodicules.These levels are regulated by differentially expressed genes.展开更多
In order to let drug addicts withdraw their toxic ma-nia, the work of drug prohibiting must be launched extensively to construct a quiet environment, so we put forward a systematic engineering imagine, which includes ...In order to let drug addicts withdraw their toxic ma-nia, the work of drug prohibiting must be launched extensively to construct a quiet environment, so we put forward a systematic engineering imagine, which includes a comprehensive administration of medical psychology and society. Now we put forward the following report to explore the direction of the World Health Organization (WHO).展开更多
Agrobacterium-mediated transformation has been widely used in plants.However,the mechanism in plant cells’response to Agrobacterium infection was very complex.The mechanism of the determinants in host cell remains ob...Agrobacterium-mediated transformation has been widely used in plants.However,the mechanism in plant cells’response to Agrobacterium infection was very complex.The mechanism of the determinants in host cell remains obscure,especially in barley,which is recalcitrant for Agrobacterium-mediated transformation.In the present study,microspore-derived embryogenic calli(MDEC)from barley elite cultivar were employed as unique subjects to characterize the mechanisms during the Agrobacterium infection process.Hua 30 MDEC can be successfully infected by Agrobacterium.RNA-sequencing at different infection points(0,2,6,12,24 hpi)was performed.The average expressional intensity of the whole genomics increased from 0 to 2 hpi,and then decreased subsequently.More upregulated than downregulated differentially expressed genes(DEGs)were counted at the same time.GO enrichment analysis showed that protein modification was significantly overrepresented in upregulated DEGs.Chromosome-related biological processes,gene expression and cellular metabolic processes were significantly overrepresented in downregulated DEGs.KEGG analysis showed that plant defense responses,phenylpropanoid biosynthesis and biosynthesis of amino acids were significantly enriched across the infection time course.Nine DEGs related to defense responses were identified.All DEGs were upregulated from 2 to 24 hpi.We speculate that these genes are possibly related to Agrobacterium infection.These findings will provide deep insights into the molecular events occurring during the process of Agrobacterium-mediated transformation.展开更多
Phytohormones play important roles in plant growth and development,and polyploids are thought to be an important method for plant breeding.However,the relationship between ploidy and phytohormone is still unclear.In t...Phytohormones play important roles in plant growth and development,and polyploids are thought to be an important method for plant breeding.However,the relationship between ploidy and phytohormone is still unclear.In this study,barley at three ploidy levels were produced by microspore culture.Therefore,we further analyzed the phytohormone content in the shoots and roots of the three kinds of barley materials to study the effect of ploidy on phytohormones accumulation and distribution.The results showed that Abscisic acid(ABA),gibberellin(GA),jasmonic acid(JA),auxin(IAA),salicylic acid(SA)and cytokinin(CTK)were successfully determined in shoots and roots using LC-MS(liquid chromatography mass spectrometry).By comparing the shoots of the haploid and diploid plants,it was found that the distribution trend of the six phytohormones was consistent,and another consistent trend was found in the roots of the diploid and tetraploid plants.In addition,we further analyzed the shoot/root ratio of the different phytohormones to identify the potential differences for haploid,diploid and tetraploid.Here,the relationship between ploidy and phytohormone we provided would provide new insights into understanding the new phenotypes that occur in polyploid species.展开更多
Successful reproduction depends on the stable germination and growth of the pollen tubes(PT).However,the molecular mechanisms involved in rice PT growth and development remain largely unknown.In a previous study,micro...Successful reproduction depends on the stable germination and growth of the pollen tubes(PT).However,the molecular mechanisms involved in rice PT growth and development remain largely unknown.In a previous study,microarray transcriptome analysis identified 627 genes preferentially expressed in the tricellular and germinating pollen of rice(i.e.,Oryza sativa ssp.japonica).To elucidate key genes involved in the gene transfer process facilitated by male gametophytes,we systematically screened T-DNA lines containing disrupted sequences that corresponded to these 627 genes and analyzed the genotypes of heterozygote progeny from 107 T-DNA-indexed lines covering 105 genes.We found that 42 lines exhibited a distorted segregation ratio among the wild-type(WT),heterozygote(HT),and homozygote(HM)genotypes,which deviated from the expected Mendelian ratio of 1:2:1(WT:HT:HM).Further characterization using CRISPR/Cas9 mutants revealed that knockout mutants of certain genes that exhibited segregation distortion in the T-DNA insertion region were completely sterile.Moreover,even when T-DNA insertion lines followed Mendelian segregation patterns,sterility could be induced by simultaneously mutating functionally redundant genes,thereby overcoming genetic compensation.Interestingly,although some T-DNA insertion lines exhibited segregation ratios approximating 1:1:0,the corresponding CRISPR/Cas9 mutants produced homozygous seeds and showed partial sterility.Partial sterility suggests that despite mutant pollen grains being less competitive than WT pollen,they retain their fertilization potential under relaxed competition from WT pollen.Beyond mutant-based analysis,transcriptomic profiling of sterile mutant lines provided additional insight into the regulatory relationship between key germination regulators and the 105 target genes studied here.Overall,this study demonstrates the effectiveness of a multi-pronged strategy to accelerate the identification of defective phenotypes using mutant studies and provides valuable genetic resources for inducing novel male sterility in rice.展开更多
Convergent and divergent evolution lead to plants with stronger adaptability to higher temperatures,thus averting crop biomass yield reductions.NADP-dependent malate dehydrogenase(NADP-MDH)is a redox-regulated enzyme ...Convergent and divergent evolution lead to plants with stronger adaptability to higher temperatures,thus averting crop biomass yield reductions.NADP-dependent malate dehydrogenase(NADP-MDH)is a redox-regulated enzyme that catalyzes the reversible reduction of oxaloacetate to malate.The sole NADP-MDH gene in rice,OsMDH8.2,is expressed in mesophyll cells of photosynthetic organs and various sink tissues.However,it is unknown whether NADP-MDH functions in heat stress in rice.We characterized a transgenic OsMDH8.2 overexpression line under thermal stress treatment(40℃).The transgenic line exhibited better adaptability to heat stress than the wild type;it better maintained biomass and a lower surface temperature through stomatal closure,and photosynthetic activity was less affected.OsMDH8.2 was found to affect peroxidase activity by reducing the hydrogen peroxide content in flag leaves after 3 and 5 days of thermal stress.Analysis results of OsMDH8.2 knockout lines confirmed that OsMDH8.2 contributes to heat tolerance.Transcriptome and metabolome analyses demonstrated that OsMDH8.2 plays a key role in energy homeostasis by reducing tricarboxylic acid cycle activity while inducing the glyoxylate cycle to produce more energy,and by regulating amino acid metabolism to rescue heatstress damage.Collectively,these results suggest that OsMDH8.2 enhances glyoxylate cycle efficiency,resulting in lower carbon dioxide release into the environment through stomatal closure,providing an excellent strategy for improving plant heat tolerance through genetic engineering.展开更多
Pollen hydration,germination,and tube growth are vital processes for the successful fertilization of flowering plants.These processes involve complex signaling pathways.Reactive oxygen species(ROS)generated in apoplas...Pollen hydration,germination,and tube growth are vital processes for the successful fertilization of flowering plants.These processes involve complex signaling pathways.Reactive oxygen species(ROS)generated in apoplast involves signaling for the cell wall expansion during tube growth,however molecular regulators are less known.We identified pollen-specific receptor-like kinase(OsPRK)family genes from rice(Oryza sativa),which have conserved leucine-rich repeat(LRR)and kinase domains.To understand the function of these genes,we produced single and triple mutations for OsPRK1,OsPRK2,and OsPRK3 using the clustered regularly interspaced palindromic repeats(CRISPR/Cas9)system.Among these mutants,triple knockout(KO)lines(osprk1/2/3)exhibited the male-sterile phenotype with normal vegetative growth and floret formation.Through cytological analysis,we confirmed that the reduced seed fertility was due to defects in pollen hydration and germination with low ROS accumulation.This defect of pollen germination was partially recovered by treatment with exogenous H_(2)O_(2).We also confirmed that OsPRKs could interact with the LRR extension protein.Our results suggest that rice PRKs redundantly play a role in ROS signaling for pollen hydration and germination,and fertility can be controlled by exogenous application.展开更多
Rice eating and cooking quality(ECQ)is significantly influenced by the physicochemical properties of rice starch.This study integrates whole-genome resequencing,transcriptomic data,and phenotypic analysis to identify t...Rice eating and cooking quality(ECQ)is significantly influenced by the physicochemical properties of rice starch.This study integrates whole-genome resequencing,transcriptomic data,and phenotypic analysis to identify the genetic factors that regulate transcript expression levels and contribute to phenotypic variation in rice ECQ traits.A TWAS(transcriptome-wide association study)identified 285 transcripts linked to 6 ECQ traits.Genome-wide mapping of these transcripts revealed 21747 local eQTLs(expression quantitative trait loci)and 45158 distal eQTLs.TWAS and eQTL analysis detected several known and novel genes,including starch synthesis-related genes,heat shock proteins,transcription factors,genes related to ATP accumulation,and UDP-glucosyltransferases,showcasing the complex genetic regulation of rice ECQ.WGCNA(weighted gene co-expression network analysis)uncovered key co-expression networks,including a module that links alpha-globulin1(GLB1)tostarchandsucrosemetabolism.GeneticdiversityanalysisoftheGLB1geneacrossaKorean rice collection identified 26 haplotypes,with indica and aus forming 7 and 3 haplotypes,respectively,which showedsignificantphenotypiceffectsonECQtraits.CRISPR-Cas9-createdknockoutlinesvalidatedthesefind-ings,demonstrating that loss of GLB1 function caused significant changes in seed storage proteins,reduced amylose content,altered starch granules,and modified pasting properties without affecting plant phenotypes.By integrating TWAS,eQTL mapping,haplotype analysis,gene expression networks,and CRISPR validation,this study establishes GLB1 as a regulator of ECQ,linking starch biosynthesis and protein accumulation path-ways.This transcriptogenomic convergence approach provides novel insights into the genetic regulation of ECQ in rice,demonstrating its effectiveness for characterizing complex traits and enabling precision breeding.展开更多
Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we ide...Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 （OsDOF11）, which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdofll mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type （WT） plants. Although sucrose enhanced root elongation in young WT seedlings, this enhance- ment did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdofll plants than in the WT. Expression of four Sucrose Transporter （SUT） genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters （SWEET） genes, OsSWEETll and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOFll directly binds the promoter regions of SUT1, OsSWEETll, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apopiastic loading is coordinately controlled by OsDOFll. We also observed that osdofll mutant plants were less susceptible to infection byXanthomonas oryzae pathovar oryzae, suggesting that OsDOFll participates in sugar distribution during pathogenic in- vasion. Collectively, these results suggest that OsDOFll modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.展开更多
Lignin is an important factor affecting agricultural traits, biofuel production, and the pulping industry. Most lignin biosynthesis genes and their regulatory genes are expressed mainly in the vascular bundles of stem...Lignin is an important factor affecting agricultural traits, biofuel production, and the pulping industry. Most lignin biosynthesis genes and their regulatory genes are expressed mainly in the vascular bundles of stems and leaves, preferentially in tissues undergoing Iignification. Other genes are poorly expressed during normal stages of development, but are strongly induced by abiotic or biotic stresses. Some are expressed in non-lignifying tissues such as the shoot apical meristem. Alterations in lignin levels affect plant develop- ment. Suppression of lignin biosynthesis genes causes abnormal phenotypes such as collapsed xylem, bending stems, and growth retardation. The loss of expression by genes that function early in the lignin biosynthesis pathway results in more severe developmental phenotypes when compared with plants that have mutations in later genes. Defective lignin deposition is also associated with phenotypes of seed shattering or brittle culm. MYB and NAC transcriptional factors function as switches, and some homeobox proteins negatively control lignin biosynthesis genes. Ectopic deposition caused by overexpression of lignin biosynthesis genes or master switch genes induces curly leaf formation and dwarfism.展开更多
Nucleotide-binding leucine-rich repeat(NLR)proteins play critical roles in plant immunity.However,how NLRs are regulated and activate defense signaling is not fully understood.The rice(Oryza sativa)NLR receptor Piz-t ...Nucleotide-binding leucine-rich repeat(NLR)proteins play critical roles in plant immunity.However,how NLRs are regulated and activate defense signaling is not fully understood.The rice(Oryza sativa)NLR receptor Piz-t confers broad-spectrum resistance to the fungal pathogen Magnaporthe oryzae and the RING-type E3 ligase AVRPIZ-T INTERACTING PROTEIN 10(APIP10)negatively regulates Piz-t accumulation.In this study,we found that APIP10 interacts with two rice transcription factors,VASCULAR PLANT ONEZINC FINGER 1(OsVOZ1)and OsVOZ2,and promotes their degradation through the 26S proteasome pathway.OsVOZ1 displays transcriptional repression activity while OsVOZ2 confers transcriptional activation activity in planta.The osvoz1 and osvoz2 single mutants display modest but opposite M.oryzae resistance in the non-Piz-t background.However,the osvoz1 osvoz2 double mutant exhibits strong dwarfism and cell death,and silencing of both genes via RNA interference also leads to dwarfism,mild cell death,and enhanced resistance to M.oryzae in the non-Piz-t background.Both OsVOZ1 and OsVOZ2 interact with Piz-t.Double silencing of OsVOZ1 and OsVOZ2 in the Piz-t background decreases Piz-t protein accumulation and transcription,reactive oxygen species-dependent cell death,and resistance to M.oryzae containing AvrPiz-t.Taken together,these results indicate that OsVOZ1 and OsVOZ2 negatively regulate basal defense but contribute positively to Piz-t-mediated immunity.展开更多
Rice （Oryza sativa） is one of the most important staple food crops for more than half of the world＇s population. The demand is increasing for food security because of population growth and environmental challenges ...Rice （Oryza sativa） is one of the most important staple food crops for more than half of the world＇s population. The demand is increasing for food security because of population growth and environmental challenges triggered by climate changes. This scenario has led to more interest in developing crops with greater productivity and sustainability. The process of genetic transformation, a major tool for crop improvement, utilizes promoters as one of its key elements. Those promoters are generally divided into three types： constitutive, spatiotemporal, and condition-dependent. Tran- scriptional control of a constitutive promoter often leads to reduced plant growth, due to a negative effect of accumu- lated molecules during cellular functions or energy consump- tion. To maximize the effect of a transgene on transgenic plants, it is better to use condition-dependent or tissue- specific promoters. However, until now, those types have not been as widely applied in crop biotechnology. In this review, we introduce and discuss four groups of tissue-specific promoters （5o promoters in total） and six groups of condition-dependent promoters （27 promoters）. These pro- moters can be utilized to fine-tune desirable agronomic traits and develop crops with tolerance to various stresses, enhanced nutritional value, and advanced productivity.展开更多
Jasmonic acid （JA） functions in plant development, including senescence and immunity. Arabidopsis thaliana CORONATINE INSENSITIVE 1 encodes a JA receptor and functions in the JA‐responsive signaling pathway. The Ar...Jasmonic acid （JA） functions in plant development, including senescence and immunity. Arabidopsis thaliana CORONATINE INSENSITIVE 1 encodes a JA receptor and functions in the JA‐responsive signaling pathway. The Arabidopsis genome harbors a single COI gene, but the rice （Oryza sativa） genome harbors three COI homologs, OsCOI1a, OsCOI1b, and OsCOI2. Thus, it remains unclear whether each OsCOI has distinct, additive, synergistic, or redundant func-tions in development. Here, we use the oscoi1b‐1 knockout mutants to show that OsCOI1b mainly affects leaf senescence under senescence‐promoting conditions. oscoi1b‐1 mutants stayed green during dark‐induced and natural senescence, with substantial retention of chlorophylls and photosyn-thetic capacity. Furthermore, several senescence‐associated genes were downregulated in oscoi1b‐1 mutants, including homologs of Arabidopsis thaliana ETHYLENE INSENSITIVE 3 and ORESARA 1, important regulators of leaf senescence. These results suggest that crosstalk between JA signaling and ethylene signaling affects leaf senescence. The Arabidopsis coi1‐1 plants containing 35S：OsCOI1a or 35S：OsCOI1b rescued the delayed leaf senescence during dark incubation, sug-gesting that both OsCOI1a and OsCOI1b are required for promoting leaf senescence in rice. oscoi1b‐1 mutants showed significant decreases in spikelet fertility and grain weight, leading to severe reduction of grain yield, indicating that OsCOI1‐mediated JA signaling affects spikelet fertility and grain filling.展开更多
Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus （QTL） mapping and candidate gene analysis using ...Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus （QTL） mapping and candidate gene analysis using whole- genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 （OsPRR37; hereafter PRR37） is respon- sible for the Early heading7-2 （EH7-2）/Heading date2 （Hd2） QTL which was identified from a cross of late-heading rice ＇Milyang23 （M23）＇ and early-heading rice ＇H143＇. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT （CONSTANS, CO-like, and TOC1） domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day condi- tions, and are adapted to the northernmost regions of rice cultivation, up to 53~ N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and GhdT/ Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.展开更多
Biotic and abiotic stresses impose a serious limitation on crop productivity worldwide. Prior or simultaneous exposure to one type of stress often affects the plant response to other stresses, indicating extensive ove...Biotic and abiotic stresses impose a serious limitation on crop productivity worldwide. Prior or simultaneous exposure to one type of stress often affects the plant response to other stresses, indicating extensive overlap and cross-talk between stress-response signaling pathways. Systems biology approaches that integrate large genomic and prot-eomic data sets have facilitated identification of candidate genes that govern this stress-regulatory crosstalk. Recently, we constructed a yeast two-hybrid map around three rice proteins that control the response to biotic and abiotic stresses, namely the immune receptor XA21, which confers resistance to the Gram-negative bacterium, Xanthomonas oryzae pv. oryzae; NH1, the rice ortholog of NPR1, a key regulator of systemic acquired resistance; and the ethylene-responsive transcription factor, SUBIA, which confers tolerance to submergence stress. These studies coupled with transcriptional profiling and co-expression analyses identified a suite of proteins that are positioned at the interface of biotic and abiotic stress responses, including mitogen-activated protein kinase 5 （OsMPK5）, wall-associated kinase 25 （WAK25）, sucrose non-fermenting-l-related protein kinase-1 （SnRK1）, SUBIA binding protein 23 （SAB23）, and several WRKY family tran- scription factors. Emerging evidence suggests that these genes orchestrate crosstalk between biotic and abiotic stresses through a variety of mechanisms, including regulation of cellular energy homeostasis and modification of synergistic and/or antagonistic interactions between the stress hormones salicylic acid, ethylene, jasmonic acid, and abscisic acid.展开更多
Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.I...Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.展开更多
基金Project supported by the National Natural Science Foundation of China(No. 50608064)the Natural Science Foundation of Zhejiang Province(No. Y505031)the National Post-doctoral Science Foundation ofChina (No. 2005037296)
文摘The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake were investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria （DPB） sludge. The lab-scale experiments were accomplished under conditions of various nitrite concentrations （5.5, 9.5, and 15 mg/L） and mixed liquor suspended solids （MLSS） （1844, 3231, and 6730 mg/L）. The results obtained confirmed that nitrite, MLSS, and pH were key factors, which had a significant impact on anaerobic phosphorus release and anoxic phosphorus uptake in the biological phosphorous removal process. The nitrites were able to successfully act as electron acceptors for phosphorous uptake at a limited concentration between 5.5 and 9.5 mg/L. The denitrification and dephosphorous were inhibited when the nitrite concentration reached 15 mg/L. This observation indicated that the nitrite would not inhibit phosphorus uptake before it exceeded a threshold concentration. It was assumed that an increase of MLSS concentration from 1844 mg/L to 6730 mg/L led to the increase of denitrification and anoxic P-uptake rate. On the contrary, the average P-uptake/N denitrifying reduced from 2.10 to 1.57 mg PO4^3--P/mg NO3^--N. Therefore, it could be concluded that increasing MLSS of the DEPHANOX system might shorten the reaction time of phosphorus release and anoxic phosphorus uptake. However, excessive MLSS might reduce the specific denitrifying rate. Meanwhile, a rapid pH increase occurred at the beginning of the anoxic conditions as a result of denitrification and anoxic phosphate uptake. Anaerobic P release rate increased with an increase in pH. Moreover, when pH exceeded a relatively high value of 8.0, the dissolved P concentration decreased in the liquid phase, because of chemical precipitation. This observation suggested that pH should be strictly controlled below 8.0 to avoid chemical precipitation if the biological denitrifying phosphorus removal capability is to be studied accurately.
基金Supported by the Knowledge Innovation Program of the Chinese Adademy of Sciences (No. KZCX3-SW-215)Special Project for Marine Public Walfare Industry (No. 200705010)
文摘The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH4-, NO3-, NO2- as well as the total dissolved inorganic nitrogen （DIN）. The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 ~mol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and could easily lead to phytoplankton blooms in nature if discarded with no treatment. The de-eutrophication abilities of U. pertusa varied greatly and depended mainly on the original eutrophic level the U. pertusa material was derived from. U. pertusa used to living in low DIN conditions had poor DIN removal abilities, while materials cultured in DIN-enriched seawater showed strong de-eutrophication abilities. In other words, the de-eutrophication ability of U. pertusa was evidently induced by high DIN levels. The de-eutrophication capacity of U. pertusa seemed to also be light dependent, because it was weaker in darkness than under illumination. However, no further improvement in the de-eutrophication capacity of U. pertusa was observed once the light intensity exceeded 300 pmolM2 S1. Results of semi-continuous wastewater replacement experiments showed that U. pertusa permanently absorbed nutrients from eutrophicated wastewater at a mean rate of 299 mg/kg fresh weight per day （126 mg/kg DIN during the night, 173 mg/kg in daytime）. Based on the above results, engineered de-eutrophication of wastewater by using a U. pertusa filter system seems feasible. The algal quantity required to purify all the eutrophicated outflow wastewater from the Qingdao Yihai Hatchery Center into oligotrophic level I dean seawater was also estimated using the daily discharged wastewater, the average DIN concentration released and the de-eutrophication capacity of U. pertusa.
基金supported by funds from the National Key Research and Development Program of China (2016YFD0100903)
文摘Non-specific lipid transfer proteins(nsLTPs) are small, basic proteins that are characterized by an eight-cysteine motif. The biological functions of these proteins have been reported to involve plant reproduction and biotic or abiotic stress response. With the completion of the barley genome sequence, a genome-wide analysis of nsLTPs in barley(Hordeum vulgare L.)(HvLTPs) will be helpful for understanding the function of nsLTPs in plants. We performed a genome-wide analysis of the nsLTP gene family in barley and identified 70 nsLTP genes,which can be divided into five types(1, 2, C, D, and G). Each type of nsLTPs shares similar exon and intron gene structures. Expression analysis showed that barley nsLTPs have diverse expression patterns, revealing their various roles. Our results shed light on the phylogenetic relationships and potential functions of barley nsLTPs and will be useful for future studies of barley development and molecular breeding.
文摘In order to</span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> study the meat quality characteristics of </span><span style="font-family:Verdana;">Ningdu</span><span style="font-family:Verdana;"> yellow rooster, the 7 indexes of 120 healthy </span><span style="font-family:Verdana;">Ningdu</span><span style="font-family:Verdana;"> yellow rooster</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> after </span><span style="font-family:Verdana;">slaughter</span><span style="font-family:Verdana;"> at the age of 16 weeks were determined, and correlation analysis, regression analysis </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> principal component analysis were carried out among the indexes.</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The results showed that the variation coefficient of PH value was smaller than that of water drop rate and meat colorimetric, and the lactic acid produced by anaerobic glycolysis of glycogen in chicken meat was slower.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Through correlation analysis, the 24-hour drip rate was strongly correlated with the 48-hour drip rate (coefficient ≥</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.7,</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">p</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">≤</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.05), and the other indicators were independent of each other.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">By means of</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> regression analysis, the regression equation (fitting degree R</span><sup><span style="font-family:Verdana;">2</span></sup></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">=</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">0.984) of </span><span style="font-family:Verdana;">24</span><span style="font-family:Verdana;">- and 48-hour drip rate was established.</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Principal component analysis synthesized 7 indicators into 3 principal components, with a cumulative contribution rate of 70.13%, indicating that the meat quality of Ningdu Yellow chicken rooster is mainly selected by water drop rate, PH value </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> meat color test.
基金the National Key Research and Development Program of China,China(2018YFD0300901)the Science and Technology Service Programof Chinese Academy of Sciences,China(KFJ-STS-ZDTP-054)+2 种基金the Key Program of 13th Five-Year Plan,Hefei Institutes of Physical Science,Chinese Academy of Sciences,China(No.kp-2017-21)Shanghai Agriculture Applied Technology Development Program,China(G2015060104)the Opening Fund of State Key Laboratory of Crop Genetics and Germplasm Enhancement,China(ZW2013003).
文摘Wheat is one of the most important staple crops worldwide.Fusarium head blight severely reduces wheat yield and quality.Cultivation of a novel type of cleistogamous wheat mutant,ZK001,which was created by static magnetic field treatment,is a new strategy for controlling Fusarium head blight.However,little is known about the mechanism of cleistogamy in wheat.The present study demonstrated that anthers of ZK001 were retained on the glumes at all flowering stages,whereas those of YM18 were extruded from the paleae and lemmae.There was a clear difference in the morphological characteristics of lodicules between YM18 and ZK001.Lodicule calcium and potassium contents were significantly higher in YM18 than in ZK001 from white to yellow anther stages.In Fusarium head blight resistance,the diseased kernel rate and deoxynivalenol content of ZK001 were markedly lower than those of YM18 and QM725.Comparative transcriptome analysis of YM18 and ZK001 was performed to identify regulatory mechanisms of cleistogamy.The main differentially expressed genes identified in the spikelets of YM18 and ZK001 at the green anther stage were associated with cell walls,carbohydrates,phytohormones,water channel,and ion binding,transport,and homeostasis.These differentially expressed genes may play an important role in regulating cellular homeostasis,osmotic pressure,and lodicule development.The results indicate that ZK001 lost the ability to push the lemmae and paleae apart during the flowering stage because of the thin lodicules.ZK001 was speculated to provide structural barriers for Fusarium head blight during the flowering stage.The thin lodicule of ZK001 results from low levels of soluble sugar,calcium ions,and potassium ions in the lodicules.These levels are regulated by differentially expressed genes.
文摘In order to let drug addicts withdraw their toxic ma-nia, the work of drug prohibiting must be launched extensively to construct a quiet environment, so we put forward a systematic engineering imagine, which includes a comprehensive administration of medical psychology and society. Now we put forward the following report to explore the direction of the World Health Organization (WHO).
基金the Shanghai Agriculture Applied Technology Development Program,China(Grant No.G2016060102)National Key Research and Development Program of China(2018YFD1000702-5)Earmarked Fund for China Agriculture Research System(CARS-05-01A-02)。
文摘Agrobacterium-mediated transformation has been widely used in plants.However,the mechanism in plant cells’response to Agrobacterium infection was very complex.The mechanism of the determinants in host cell remains obscure,especially in barley,which is recalcitrant for Agrobacterium-mediated transformation.In the present study,microspore-derived embryogenic calli(MDEC)from barley elite cultivar were employed as unique subjects to characterize the mechanisms during the Agrobacterium infection process.Hua 30 MDEC can be successfully infected by Agrobacterium.RNA-sequencing at different infection points(0,2,6,12,24 hpi)was performed.The average expressional intensity of the whole genomics increased from 0 to 2 hpi,and then decreased subsequently.More upregulated than downregulated differentially expressed genes(DEGs)were counted at the same time.GO enrichment analysis showed that protein modification was significantly overrepresented in upregulated DEGs.Chromosome-related biological processes,gene expression and cellular metabolic processes were significantly overrepresented in downregulated DEGs.KEGG analysis showed that plant defense responses,phenylpropanoid biosynthesis and biosynthesis of amino acids were significantly enriched across the infection time course.Nine DEGs related to defense responses were identified.All DEGs were upregulated from 2 to 24 hpi.We speculate that these genes are possibly related to Agrobacterium infection.These findings will provide deep insights into the molecular events occurring during the process of Agrobacterium-mediated transformation.
基金Key Technology R&D Project of Shanghai Agriculture-developed with Science&Technology Program,China(Grant No.2018(1-2))the Natural Science Foundation of Shanghai,China(Grant No.19ZR1417000)+2 种基金the National Key Research and Development Program of China(2018YFD1000702-5)the Climbing Plan of Shanghai Academy of Agricultural Sciences(2022)the earmarked fund for China Agriculture Research System of MOF and MARA(CARS-05-01A-02).
文摘Phytohormones play important roles in plant growth and development,and polyploids are thought to be an important method for plant breeding.However,the relationship between ploidy and phytohormone is still unclear.In this study,barley at three ploidy levels were produced by microspore culture.Therefore,we further analyzed the phytohormone content in the shoots and roots of the three kinds of barley materials to study the effect of ploidy on phytohormones accumulation and distribution.The results showed that Abscisic acid(ABA),gibberellin(GA),jasmonic acid(JA),auxin(IAA),salicylic acid(SA)and cytokinin(CTK)were successfully determined in shoots and roots using LC-MS(liquid chromatography mass spectrometry).By comparing the shoots of the haploid and diploid plants,it was found that the distribution trend of the six phytohormones was consistent,and another consistent trend was found in the roots of the diploid and tetraploid plants.In addition,we further analyzed the shoot/root ratio of the different phytohormones to identify the potential differences for haploid,diploid and tetraploid.Here,the relationship between ploidy and phytohormone we provided would provide new insights into understanding the new phenotypes that occur in polyploid species.
基金supported by grants from the New Breeding TechnologiesDevelopmentProgram(RS-2024-00322278 to S.M.)the Rural Development Administration,Republic of Korea,and the National Research Foundation(NRF)of Korea,the Ministry of Education,Science and Technology(RS-2021-NR060084 to K.-H.J.,NRF-2021R1A2C2010124 to S.-K.P.,RS-2023-00217064,RS-2024-00344197 to Y.-J.K.,and RS-2021-NR062086 to W.-J.H.).
文摘Successful reproduction depends on the stable germination and growth of the pollen tubes(PT).However,the molecular mechanisms involved in rice PT growth and development remain largely unknown.In a previous study,microarray transcriptome analysis identified 627 genes preferentially expressed in the tricellular and germinating pollen of rice(i.e.,Oryza sativa ssp.japonica).To elucidate key genes involved in the gene transfer process facilitated by male gametophytes,we systematically screened T-DNA lines containing disrupted sequences that corresponded to these 627 genes and analyzed the genotypes of heterozygote progeny from 107 T-DNA-indexed lines covering 105 genes.We found that 42 lines exhibited a distorted segregation ratio among the wild-type(WT),heterozygote(HT),and homozygote(HM)genotypes,which deviated from the expected Mendelian ratio of 1:2:1(WT:HT:HM).Further characterization using CRISPR/Cas9 mutants revealed that knockout mutants of certain genes that exhibited segregation distortion in the T-DNA insertion region were completely sterile.Moreover,even when T-DNA insertion lines followed Mendelian segregation patterns,sterility could be induced by simultaneously mutating functionally redundant genes,thereby overcoming genetic compensation.Interestingly,although some T-DNA insertion lines exhibited segregation ratios approximating 1:1:0,the corresponding CRISPR/Cas9 mutants produced homozygous seeds and showed partial sterility.Partial sterility suggests that despite mutant pollen grains being less competitive than WT pollen,they retain their fertilization potential under relaxed competition from WT pollen.Beyond mutant-based analysis,transcriptomic profiling of sterile mutant lines provided additional insight into the regulatory relationship between key germination regulators and the 105 target genes studied here.Overall,this study demonstrates the effectiveness of a multi-pronged strategy to accelerate the identification of defective phenotypes using mutant studies and provides valuable genetic resources for inducing novel male sterility in rice.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20190889)the China Postdoctoral Science Foundation(2019M660130)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Convergent and divergent evolution lead to plants with stronger adaptability to higher temperatures,thus averting crop biomass yield reductions.NADP-dependent malate dehydrogenase(NADP-MDH)is a redox-regulated enzyme that catalyzes the reversible reduction of oxaloacetate to malate.The sole NADP-MDH gene in rice,OsMDH8.2,is expressed in mesophyll cells of photosynthetic organs and various sink tissues.However,it is unknown whether NADP-MDH functions in heat stress in rice.We characterized a transgenic OsMDH8.2 overexpression line under thermal stress treatment(40℃).The transgenic line exhibited better adaptability to heat stress than the wild type;it better maintained biomass and a lower surface temperature through stomatal closure,and photosynthetic activity was less affected.OsMDH8.2 was found to affect peroxidase activity by reducing the hydrogen peroxide content in flag leaves after 3 and 5 days of thermal stress.Analysis results of OsMDH8.2 knockout lines confirmed that OsMDH8.2 contributes to heat tolerance.Transcriptome and metabolome analyses demonstrated that OsMDH8.2 plays a key role in energy homeostasis by reducing tricarboxylic acid cycle activity while inducing the glyoxylate cycle to produce more energy,and by regulating amino acid metabolism to rescue heatstress damage.Collectively,these results suggest that OsMDH8.2 enhances glyoxylate cycle efficiency,resulting in lower carbon dioxide release into the environment through stomatal closure,providing an excellent strategy for improving plant heat tolerance through genetic engineering.
基金supported by grants from the National Research Foundation(NRF),Ministry of Education,Science and Technology(RS-2023-00275589 and RS-2023-00217064 to Y.-J.K.,RS-2025-00555009 to E.-J.K.,and RS-2021-NR060084 to K.-H.J.)the New Breeding Technologies Development Program(RS-2024-00322278 to S.M.)from the Rural Development Administration(RDA),Republic of Korea.
文摘Pollen hydration,germination,and tube growth are vital processes for the successful fertilization of flowering plants.These processes involve complex signaling pathways.Reactive oxygen species(ROS)generated in apoplast involves signaling for the cell wall expansion during tube growth,however molecular regulators are less known.We identified pollen-specific receptor-like kinase(OsPRK)family genes from rice(Oryza sativa),which have conserved leucine-rich repeat(LRR)and kinase domains.To understand the function of these genes,we produced single and triple mutations for OsPRK1,OsPRK2,and OsPRK3 using the clustered regularly interspaced palindromic repeats(CRISPR/Cas9)system.Among these mutants,triple knockout(KO)lines(osprk1/2/3)exhibited the male-sterile phenotype with normal vegetative growth and floret formation.Through cytological analysis,we confirmed that the reduced seed fertility was due to defects in pollen hydration and germination with low ROS accumulation.This defect of pollen germination was partially recovered by treatment with exogenous H_(2)O_(2).We also confirmed that OsPRKs could interact with the LRR extension protein.Our results suggest that rice PRKs redundantly play a role in ROS signaling for pollen hydration and germination,and fertility can be controlled by exogenous application.
基金supported by National Research Foundation of Korea(NRF)grants funded by the Korean government(MSIT)(NRF-2022R1A 4A1030348 and NRF-2023R1A2C1004432)the Development of Next-Generation Crop Breeding Technologies(RS-2024-00322378)Rural Development Administration,Republic of Korea.
文摘Rice eating and cooking quality(ECQ)is significantly influenced by the physicochemical properties of rice starch.This study integrates whole-genome resequencing,transcriptomic data,and phenotypic analysis to identify the genetic factors that regulate transcript expression levels and contribute to phenotypic variation in rice ECQ traits.A TWAS(transcriptome-wide association study)identified 285 transcripts linked to 6 ECQ traits.Genome-wide mapping of these transcripts revealed 21747 local eQTLs(expression quantitative trait loci)and 45158 distal eQTLs.TWAS and eQTL analysis detected several known and novel genes,including starch synthesis-related genes,heat shock proteins,transcription factors,genes related to ATP accumulation,and UDP-glucosyltransferases,showcasing the complex genetic regulation of rice ECQ.WGCNA(weighted gene co-expression network analysis)uncovered key co-expression networks,including a module that links alpha-globulin1(GLB1)tostarchandsucrosemetabolism.GeneticdiversityanalysisoftheGLB1geneacrossaKorean rice collection identified 26 haplotypes,with indica and aus forming 7 and 3 haplotypes,respectively,which showedsignificantphenotypiceffectsonECQtraits.CRISPR-Cas9-createdknockoutlinesvalidatedthesefind-ings,demonstrating that loss of GLB1 function caused significant changes in seed storage proteins,reduced amylose content,altered starch granules,and modified pasting properties without affecting plant phenotypes.By integrating TWAS,eQTL mapping,haplotype analysis,gene expression networks,and CRISPR validation,this study establishes GLB1 as a regulator of ECQ,linking starch biosynthesis and protein accumulation path-ways.This transcriptogenomic convergence approach provides novel insights into the genetic regulation of ECQ in rice,demonstrating its effectiveness for characterizing complex traits and enabling precision breeding.
文摘Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long- distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 （OsDOF11）, which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdofll mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type （WT） plants. Although sucrose enhanced root elongation in young WT seedlings, this enhance- ment did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdofll plants than in the WT. Expression of four Sucrose Transporter （SUT） genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters （SWEET） genes, OsSWEETll and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOFll directly binds the promoter regions of SUT1, OsSWEETll, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apopiastic loading is coordinately controlled by OsDOFll. We also observed that osdofll mutant plants were less susceptible to infection byXanthomonas oryzae pathovar oryzae, suggesting that OsDOFll participates in sugar distribution during pathogenic in- vasion. Collectively, these results suggest that OsDOFll modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.
基金supported,in part,by grants from the Basic Research Promotion Fund,Republic of Korea(NFR2007-0093862)the Next-Generation BioGreen 21 Program for Agriculture and Technology Development(No.PJ01108001)+1 种基金the Rural Development Administration,Republic of KoreaKyung Hee University(20130214)
文摘Lignin is an important factor affecting agricultural traits, biofuel production, and the pulping industry. Most lignin biosynthesis genes and their regulatory genes are expressed mainly in the vascular bundles of stems and leaves, preferentially in tissues undergoing Iignification. Other genes are poorly expressed during normal stages of development, but are strongly induced by abiotic or biotic stresses. Some are expressed in non-lignifying tissues such as the shoot apical meristem. Alterations in lignin levels affect plant develop- ment. Suppression of lignin biosynthesis genes causes abnormal phenotypes such as collapsed xylem, bending stems, and growth retardation. The loss of expression by genes that function early in the lignin biosynthesis pathway results in more severe developmental phenotypes when compared with plants that have mutations in later genes. Defective lignin deposition is also associated with phenotypes of seed shattering or brittle culm. MYB and NAC transcriptional factors function as switches, and some homeobox proteins negatively control lignin biosynthesis genes. Ectopic deposition caused by overexpression of lignin biosynthesis genes or master switch genes induces curly leaf formation and dwarfism.
基金This work was supported by grants from the National Natural Science Foundation of China(31822041,31901829,and 31972225)the National Key Research and Development Program of China(2016YFD0100600)the China Postdoctoral Science Foundation(2019M660894).
文摘Nucleotide-binding leucine-rich repeat(NLR)proteins play critical roles in plant immunity.However,how NLRs are regulated and activate defense signaling is not fully understood.The rice(Oryza sativa)NLR receptor Piz-t confers broad-spectrum resistance to the fungal pathogen Magnaporthe oryzae and the RING-type E3 ligase AVRPIZ-T INTERACTING PROTEIN 10(APIP10)negatively regulates Piz-t accumulation.In this study,we found that APIP10 interacts with two rice transcription factors,VASCULAR PLANT ONEZINC FINGER 1(OsVOZ1)and OsVOZ2,and promotes their degradation through the 26S proteasome pathway.OsVOZ1 displays transcriptional repression activity while OsVOZ2 confers transcriptional activation activity in planta.The osvoz1 and osvoz2 single mutants display modest but opposite M.oryzae resistance in the non-Piz-t background.However,the osvoz1 osvoz2 double mutant exhibits strong dwarfism and cell death,and silencing of both genes via RNA interference also leads to dwarfism,mild cell death,and enhanced resistance to M.oryzae in the non-Piz-t background.Both OsVOZ1 and OsVOZ2 interact with Piz-t.Double silencing of OsVOZ1 and OsVOZ2 in the Piz-t background decreases Piz-t protein accumulation and transcription,reactive oxygen species-dependent cell death,and resistance to M.oryzae containing AvrPiz-t.Taken together,these results indicate that OsVOZ1 and OsVOZ2 negatively regulate basal defense but contribute positively to Piz-t-mediated immunity.
基金supported by the Cooperative Research Program for Agriculture Science and Technology Development(Project title:Global identification and functional study of rice genes for enhancement of root development and nutrient use efficiency using genome information,project no.PJ01100401)
文摘Rice （Oryza sativa） is one of the most important staple food crops for more than half of the world＇s population. The demand is increasing for food security because of population growth and environmental challenges triggered by climate changes. This scenario has led to more interest in developing crops with greater productivity and sustainability. The process of genetic transformation, a major tool for crop improvement, utilizes promoters as one of its key elements. Those promoters are generally divided into three types： constitutive, spatiotemporal, and condition-dependent. Tran- scriptional control of a constitutive promoter often leads to reduced plant growth, due to a negative effect of accumu- lated molecules during cellular functions or energy consump- tion. To maximize the effect of a transgene on transgenic plants, it is better to use condition-dependent or tissue- specific promoters. However, until now, those types have not been as widely applied in crop biotechnology. In this review, we introduce and discuss four groups of tissue-specific promoters （5o promoters in total） and six groups of condition-dependent promoters （27 promoters）. These pro- moters can be utilized to fine-tune desirable agronomic traits and develop crops with tolerance to various stresses, enhanced nutritional value, and advanced productivity.
基金the support of ‘Cooperative Research Program for Agriculture Science & Technology Development (PJ00812802)’, Rural Development Administration, Republic of Korea
文摘Jasmonic acid （JA） functions in plant development, including senescence and immunity. Arabidopsis thaliana CORONATINE INSENSITIVE 1 encodes a JA receptor and functions in the JA‐responsive signaling pathway. The Arabidopsis genome harbors a single COI gene, but the rice （Oryza sativa） genome harbors three COI homologs, OsCOI1a, OsCOI1b, and OsCOI2. Thus, it remains unclear whether each OsCOI has distinct, additive, synergistic, or redundant func-tions in development. Here, we use the oscoi1b‐1 knockout mutants to show that OsCOI1b mainly affects leaf senescence under senescence‐promoting conditions. oscoi1b‐1 mutants stayed green during dark‐induced and natural senescence, with substantial retention of chlorophylls and photosyn-thetic capacity. Furthermore, several senescence‐associated genes were downregulated in oscoi1b‐1 mutants, including homologs of Arabidopsis thaliana ETHYLENE INSENSITIVE 3 and ORESARA 1, important regulators of leaf senescence. These results suggest that crosstalk between JA signaling and ethylene signaling affects leaf senescence. The Arabidopsis coi1‐1 plants containing 35S：OsCOI1a or 35S：OsCOI1b rescued the delayed leaf senescence during dark incubation, sug-gesting that both OsCOI1a and OsCOI1b are required for promoting leaf senescence in rice. oscoi1b‐1 mutants showed significant decreases in spikelet fertility and grain weight, leading to severe reduction of grain yield, indicating that OsCOI1‐mediated JA signaling affects spikelet fertility and grain filling.
文摘Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus （QTL） mapping and candidate gene analysis using whole- genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 （OsPRR37; hereafter PRR37） is respon- sible for the Early heading7-2 （EH7-2）/Heading date2 （Hd2） QTL which was identified from a cross of late-heading rice ＇Milyang23 （M23）＇ and early-heading rice ＇H143＇. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT （CONSTANS, CO-like, and TOC1） domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day condi- tions, and are adapted to the northernmost regions of rice cultivation, up to 53~ N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and GhdT/ Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.
文摘Biotic and abiotic stresses impose a serious limitation on crop productivity worldwide. Prior or simultaneous exposure to one type of stress often affects the plant response to other stresses, indicating extensive overlap and cross-talk between stress-response signaling pathways. Systems biology approaches that integrate large genomic and prot-eomic data sets have facilitated identification of candidate genes that govern this stress-regulatory crosstalk. Recently, we constructed a yeast two-hybrid map around three rice proteins that control the response to biotic and abiotic stresses, namely the immune receptor XA21, which confers resistance to the Gram-negative bacterium, Xanthomonas oryzae pv. oryzae; NH1, the rice ortholog of NPR1, a key regulator of systemic acquired resistance; and the ethylene-responsive transcription factor, SUBIA, which confers tolerance to submergence stress. These studies coupled with transcriptional profiling and co-expression analyses identified a suite of proteins that are positioned at the interface of biotic and abiotic stress responses, including mitogen-activated protein kinase 5 （OsMPK5）, wall-associated kinase 25 （WAK25）, sucrose non-fermenting-l-related protein kinase-1 （SnRK1）, SUBIA binding protein 23 （SAB23）, and several WRKY family tran- scription factors. Emerging evidence suggests that these genes orchestrate crosstalk between biotic and abiotic stresses through a variety of mechanisms, including regulation of cellular energy homeostasis and modification of synergistic and/or antagonistic interactions between the stress hormones salicylic acid, ethylene, jasmonic acid, and abscisic acid.
基金financially supported by the National Key Agriculture Projects(NK2022060101)National Key Research and Development Program(2022YFF1002900,2020YFE0202900)+3 种基金the Fundamental Research Funds for the Central University(XUEKEN2022012)Jiangsu Provincial Key Research and Development Program(BE2021375,BE2022346)Seed Industry Revitalization Project of Jiangsu Province(JBGS2021006,2021013,2021047)Joint Research of Improved Wheat Variety of Anhui,and Jiangsu Agricultural Technology System(JATS)(JATS[2021]463,JATS[2022]464).
文摘Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.
