Epigenetics refers to the study of heritable changes in gene function that do not involve changes in the DNA sequence. Such effects on cellular and physiological phenotypic traits may result from external or environme...Epigenetics refers to the study of heritable changes in gene function that do not involve changes in the DNA sequence. Such effects on cellular and physiological phenotypic traits may result from external or environmental factors or be part of normal developmental program. In eukaryotes, DNA wraps on a histone octamer(two copies of H2A, H2B, H3 and H4) to form nucleosome, the fundamental unit of chromatin. The structure of chromatin is subjected to a dynamic regulation through multiple epigenetic mechanisms, including DNA methylation, histone posttranslational modifications(PTMs), chromatin remodeling and noncoding RNAs. As conserved regulatory mechanisms in gene expression, epigenetic mechanisms participate in almost all the important biological processes ranging from basal development to environmental response. Importantly, all of the major epigenetic mechanisms in mammalians also occur in plants. Plant studies have provided numerous important contributions to the epigenetic research. For example, gene imprinting, a mechanism of parental allele-specific gene expression, was firstly observed in maize; evidence of paramutation, an epigenetic phenomenon that one allele acts in a single locus to induce a heritable change in the other allele, was firstly reported in maize and tomato.Moreover, some unique epigenetic mechanisms have been evolved in plants. For example, the 24-nt siRNA-involved RNA-directed DNA methylation(RdDM) pathway is plant-specific because of the involvements of two plant-specific DNA-dependent RNA polymerases, Pol IV and Pol V. A thorough study of epigenetic mechanisms is of great significance to improve crop agronomic traits and environmental adaptability. In this review, we make a brief summary of important progress achieved in plant epigenetics field in China over the past several decades and give a brief outlook on future research prospects.We focus our review on DNA methylation and histone PTMs, the two most important aspects of epigenetic mechanisms.展开更多
Plant centromeres are generally composed of tandem arrays of simple repeats that form a complex chromosome locus where the kinetochore forms and microtubules attach during mitosis and meiosis. Each chromosome has one ...Plant centromeres are generally composed of tandem arrays of simple repeats that form a complex chromosome locus where the kinetochore forms and microtubules attach during mitosis and meiosis. Each chromosome has one centromere region, which is essential for accurate division of the genetic material. Recently, chromosomes containing two centromere regions （called dicentric chromosomes） have been found in maize and wheat. Interestingly, some dicentric chromosomes are stable because only one centromere is active and the other one is inactivated. Because such arrays maintain their typical structure for both active and inactive centromeres, the specification of centromere activity has an epigenetic component independent of the DNA sequence. Under some circumstances, the inactive centromeres may recover centromere function, which is called centromere reactivation. Recent studies have highlighted the important changes, such as DNA methylation and histone modification, that occur during centromere inactivation and reactivation.展开更多
Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicl...Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicle or spike branches during the reproductive stage,respectively,both of which are significantly impacted by hormones and genetic factors.Tillering and panicle branching are closely interconnected and exhibit high environmental plasticity.Here,we summarize the recent progress in genetic,hormonal,and environmental factors regulation in the branching of rice and wheat.This review not only provides a comprehensive overview of the current knowledge on branching mechanisms in rice and wheat,but also explores the prospects for future research aimed at optimizing crop architecture for enhanced productivity.展开更多
In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels...In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.展开更多
Vegetation response to the combined effects of human and nature has raised extensive controversy.The relative contributions of ecological restoration and multiple climate factors on vegetation variation remain unclear...Vegetation response to the combined effects of human and nature has raised extensive controversy.The relative contributions of ecological restoration and multiple climate factors on vegetation variation remain unclear.Combining spatial and temporal changes in fractional vegetation cover(FVC)and net primary productivity(NPP)from 2000 to 2021,we assessed the trend of these two indicators and quantified the impact of ecological restoration and climate factors on vegetation variation using partial correlation and residual analysis.The results indicated that:(1)From 2000 to 2021,vegetation restoration in the Taihang Mountain area was notably successful.FVC increased by 5.71%over 22 years with a change trend of 0.0018 per annum.The cumulative growth rate of NPP over the same period was 42.03%,corresponding to an average annual increase of 5.492 g(C)·m^(-2)·a^(-1).(2)During the 22-year period,the contribution rates of ecological engineering to FVC and NPP were 65.13%and 64.33%,respectively.Ecological restoration was the dominant factor affecting vegetation change,and its impact was increasing in over 90%of the regional projects.The primary climate controlling factor of NPP was precipitation,while FVC responded synergistically to precipitation(primary)and temperature(secondary).Overall,the impact of precipitation on vegetation was 1.5 times that of temperature.(3)Among various ecological restoration types,grassland restoration contributed the most to vegetation change,followed by forest land restoration.This study offers valuable scientific insights that can guide the sustainability of vegetation ecology in semi-arid mountainous areas.展开更多
Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent stu...Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent studies in crops have uncovered numerous genes that control seed size and weight,many of which function by modulating phytohormone biosynthesis,metabolism,or signaling pathways.This review provides a comprehensive overview of the genetic and molecular mechanisms by which phytohormones regulate seed size and weight and their cross-talks in modulating seed size.We highlight the functional conservation and divergence of homologous genes that control seed size across species.A particular focus is placed on those genes that have promising potential for yield improvement.Finally,we discuss current challenges in phytohormone regulation of seed size and molecular design breeding strategies for translating this knowledge into crop improvement.展开更多
Powdery mildew is a serious disease caused by Blumeria graminis f.sp.tritici(Bgt)that critically threatens the yield and quality of wheat(Triticum aestivum L.).Using effective powdery mildew resistance genes is the op...Powdery mildew is a serious disease caused by Blumeria graminis f.sp.tritici(Bgt)that critically threatens the yield and quality of wheat(Triticum aestivum L.).Using effective powdery mildew resistance genes is the optimal method for controlling this disease.Against the background of high genetic homogeneity among the modern commercial cultivars that are mainly derived from conventional interbreeding,the resistance genes from wheat relatives have especially prominent advantages.Octoploid triticale,produced from common wheat and rye(Secale cereale L.)through distant hybridization,is a new synthetic species and valuable gene donor for wheat improvement.In this study,we developed the wheat-rye line YT5 through the hybridization of octaploid triticale and two wheat lines.YT5 was confirmed to be a 6RL ditelosomic addition and 1R(1B)substitution line using genomic in situ hybridization(GISH),multicolor fluorescence in situ hybridization(mc-FISH),multicolor GISH(mc-GISH)and molecular marker analysis.Genetic analysis showed that the powdery mildew resistance in YT5 was derived from the rye chromosome arm 6RL.After inoculation with different Bgt isolates at the seedling stage,YT5 had compound reaction patterns with both obvious spores and hypersensitivity,and it gradually became highly resistant until the adult-plant stage,thus showing a resistance response significantly different from the reported Pm genes from rye chromosome 6RL.YT5 also showed promising agronomic performance,so it is expected to be an elite resistance donor for wheat improvement.To promote the transfer of the chromosome arm 6RL of YT5 in marker-assisted selection(MAS)breeding,we selected and verified two 6RL-specific kompetitive allelespecific PCR(KASP)markers that can be applied to efficiently detect this chromosome arm in different wheat backgrounds.展开更多
For fast in-situ assessment of tiller phenotypes in rice breeding,we introduce the TillerPET model,an improved transformer-based deep learning solution that permits phenotyping the number and compactness of rice tille...For fast in-situ assessment of tiller phenotypes in rice breeding,we introduce the TillerPET model,an improved transformer-based deep learning solution that permits phenotyping the number and compactness of rice tillers in images of post-harvest rice stubble.A rice tiller phenotype dataset covering three years of field data and four experimental sites across China was constructed to train and validate the model.TillerPET reports an R2 of 0.941 for counting tiller number,demonstrating state-of-the-art performance on the proposed RTP dataset.Beyond its minimal errors in estimating tiller number,TillerPET also achieves an R2 of 0.978 for characterizing tiller compactness.The two phenotypic parameters exhibit a high degree of consistency with expert breeders,offering reliable phenotypic indicators to guide further breeding.展开更多
Chromosomal DNA double-strand breaks(DSBs)are often generated in the genome of all living organisms.To combat DNA damage,organisms have evolved several DSB repair mechanisms,with nonhomologous end-joining(NHEJ)and hom...Chromosomal DNA double-strand breaks(DSBs)are often generated in the genome of all living organisms.To combat DNA damage,organisms have evolved several DSB repair mechanisms,with nonhomologous end-joining(NHEJ)and homologous recombination(HR)being the two most prominent.Although two major pathways have been extensively studied in Arabidopsis,rice and other mammals,the exact functions and differences between the two DSB repair pathways in maize still remain less well understood.Here,we characterized mre11a and rad50,mutants of HR pathway patterns,which showed drastic degradation of the typically persistent embryo and endosperm during kernel development.Loss of MRE11 or RAD50 function led to chromosomal fragments and chromosomal bridges in anaphase.While we also reported that the NHEJ pathway patterns,KU70 and KU80 are associated with developmental growth and genome stability.ku70 and ku80 both displayed an obvious dwarf phenotype.Cytological analysis of the mutants revealed extensive chromosome fragmentation in metaphase and subsequent stages.Loss of KU70/80 function upregulated the expression of genes involved in cell cycle progression and nuclear division.These results provide insights into how NHEJ and HR are mechanistically executed during different plant developmental periods and highlight a competitive and complementary relationship between the NHEJ and HR pathways for DNA double-strand break repair in maize.展开更多
A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that r...A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.展开更多
The circadian clock is a highly hierarchical network of endogenous pacemakers that primarily maintains and directs oscillations through transcriptional and translational feedback loops,which modulates an approximately...The circadian clock is a highly hierarchical network of endogenous pacemakers that primarily maintains and directs oscillations through transcriptional and translational feedback loops,which modulates an approximately 24-h cycle of endocrine and metabolic rhythms within cells and tissues.While circadian clocks regulate metabolic processes and related physiology,emerging evidence indicates that metabolism and circadian rhythm are intimately intertwined.In this review,we highlight the concept of metabolites,including lipids and other polar metabolites generated from intestinal microbial metabolism and nutrient intake,as time cues that drive changes in circadian rhythms,which in turn influence metabolism and aging.Furthermore,we discuss the roles of functional metabolites as circadian cues,paving a new direction on potential intervention targets of circadian disruption,pathological aging,as well as metabolic diseases that are clinically important.展开更多
Journal of Genetics and Genomics(JGG),launched in 1974,celebrates its 50th birthday in 2023.With continuous support from our authors,reviewers,readers,and the editorial board,JGG has made remarkable progress in the pa...Journal of Genetics and Genomics(JGG),launched in 1974,celebrates its 50th birthday in 2023.With continuous support from our authors,reviewers,readers,and the editorial board,JGG has made remarkable progress in the past year by publishing 122 papers covering major disciplines in life sciences and medical genetics with exciting discoveries.It is worthwhile to note that we have recruited 66 young talents to join JGG as junior editors,resulting in significant improvement in manuscript evaluation and journal promotion.Here,we summarize major progresses reported in JGG in 2023 fromaneditorial view.展开更多
This erratum clarifies information in the article“Nucleolar histone deacetylases HDT1,HDT2,and HDT3 regulate plant reproductive development”by Luo et al.(2021).In the section on“Phenotype of hdt mutants”,the T-DNA...This erratum clarifies information in the article“Nucleolar histone deacetylases HDT1,HDT2,and HDT3 regulate plant reproductive development”by Luo et al.(2021).In the section on“Phenotype of hdt mutants”,the T-DNA insertional knockdown mutant for HDT2(hdt2,salk_1247_A02)should be“Sail_1247_A02”in the main text and Fig.3A.展开更多
This erratum clarifies information in the Letter to the Editor“Actin polymerization induces mitochondrial distribution during collective cell migration”by Qu et al.(2023).In the section for the list of author names,...This erratum clarifies information in the Letter to the Editor“Actin polymerization induces mitochondrial distribution during collective cell migration”by Qu et al.(2023).In the section for the list of author names,“Chen Qu,Yating Kan,Hui Zuo,Mengqi Wu,Zhixiang Dong,Xinyi Wang,Qing Zhang,Heng Wang,Dou Wang,Jiong Chen”should be“Chen Qu,Yating Kan,Xinyi Wang,Hui Zuo,Mengqi Wu,Zhixiang Dong,Qing Zhang,Heng Wang,Dou Wang,Jiong Chen”.展开更多
Safflower is an important oilseed crop that has been used in traditional Chinese medicine for thousands of years because of the clinically valuable flavonoid glycosides in its flower petals.However,the biosynthesis an...Safflower is an important oilseed crop that has been used in traditional Chinese medicine for thousands of years because of the clinically valuable flavonoid glycosides in its flower petals.However,the biosynthesis and molecular regulation of these compounds are still elusive due to the lack of a high-quality reference genome and scarce identification of key biosynthetic pathway genes in a medicinal safflower variety.Here we leveraged an integrative multi-omics strategy by combining genomic,comparative genomics,and tissue-specific transcriptome profiling with biochemical analysis to identify uridine diphosphate glycosyltransferases(UGTs)for flavonoid glycoside biosynthesis in safflower.We assembled and annotated a high-quality reference genome of a medicinal safflower variety,‘Yunhong3’.A comprehensive comparative genomic analysis indicated that an evolutionary whole-genome triplication event occurring in safflower contributed to gene amplification of the flavonoid biosynthetic pathway.By combining comparative transcriptome profiling with enzymatic reactions,we identified 11 novel UGTs that could catalyze the conversion of naringenin chalcone and phloretin to the corresponding O-glycosides.Moreover,we outlined the molecular pathway of hydroxysafflor yellow A(HSYA)biosynthesis featured by 17 newly identified UGTs with promising catalytic activity,laying the foundation for the synthetic production of HSYA.Our study reports systemic genome and gene expression information for flavonoid glycoside biosynthesis in medicinal safflower and provides insights into mechanisms regulating HSYA biosynthesis,which would facilitate the genetic improvement and synthetic bioengineering design for producing clinically valuable flavonoid glycosides in safflower.展开更多
Abiotic stresses cause serious crop losses. Knowledge on genes functioning in plant responses to adverse growth conditions is essential for developing stress tolerant crops. Here we report that transgenic expression o...Abiotic stresses cause serious crop losses. Knowledge on genes functioning in plant responses to adverse growth conditions is essential for developing stress tolerant crops. Here we report that transgenic expression of MYB15, encoding a R2R3 MYB transcription factor in Arabidopsis thaliana, conferred hypersensitivity to exogenous abscisic acid （ABA） and improved tolerance to drought and salt stresses. The promoter of MYB15 was active in not only vegetative and reproductive organs but also the guard cells of stomata. Its transcript level was substantially upregulated by ABA, drought or salt treatments. Compared with wild type （WT） control, MYB15 overexpression lines were hypersensitive to ABA in germination assays, more susceptible to ABA-elicited inhibition of root elongation, and more sensitive to ABA-induced stomatal closure. In line with the above findings, the transcript levels of ABA biosynthesis （ABA1, ABA2）, signaling （AB13） and responsive genes （AtADH1, RD22, RD29B, AtEM6） were generally higher in MYB15 overexpression seedlings than in WT controls after treatment with ABA. MYB15 overexpression lines displayed improved survival and reduced water loss rates than WT control under water deficiency conditions. These overexpression lines also displayed higher tolerance to NaCI stress. Collectively, our data suggest that overexpression of MYB15 improves drought and salt tolerance in Arabidopsis possibly by enhancing the expression levels of the genes involved in ABA biosynthesis and signaling, and those encoding the stress-protective proteins.展开更多
Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic eviden...Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic evidence to show that the Arabidopsis thaliana NAC family proteins ANAC019 and ANAC055 might function as transcription activators to regulate JA-induced expression of defense genes. The role of the two NAC genes in JA signaling was examined with the anacO19 anac055 double mutant and with transgenic plants overexpressing ANACO19 or ANAC055. The anacO19 anac055 double mutant plants showed attenuated JA-induced VEGETATIVE STORAGE PROTEIN1 （VSP1） and LIPOXYGENASE2 （LOX2） expression, whereas transgenic plants overexpressing the two NAC genes showed enhanced JA-induced VSP1 and LOX2 expression. That the JA-induced expression of the two NAC genes depends on the function of COIl and AtMYC2, together with the finding that overexpression of ANACO19 partially rescued the JA-related phenotype of the atmyc2-2 mutant, has led us to a hypothesis that the two NAC proteins act downstream of AtMYC2 to regulate JA-signaled defense responses. Further evidence to substantiate this idea comes from the observation that the response of the anacO19 anac055 double mutant to a necrotrophic fungus showed high similarity to that of the atmyc2-2 mutant.展开更多
Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study...Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study, a series of wheat （cv. Chinese Spring, CS） substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene（s） of 7E was located on the short-ann （7ES） based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene（s） for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization （GISH） analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene（s） highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.展开更多
NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid （...NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid （ABA）, methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses.展开更多
In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-...In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-Cd crops (i.e., pollution-safe cultivars, the crop varieties with the ability to accumulate a low level of Cd in their edible parts when grown on polluted soil) in these areas and highlights the importance of knowledge on phenotypic variation in crop Cd accumulation for food Cd risk control. Studies on phenotypic variation in heavy metal accumulation started decades ago for a wide range of crops, and synthesis of the scattered experimental results in the literature is in need. We built a Low-Cd Crops Database based on literature research, and relevant meta-analysis was performed to quantitatively explore the phenotypic variation in Cd uptake and translocation of rice and wheat. Considerable variability existed among rice (median grain Cd bioconce nt ration factor (BCF) of 0.10) and wheat (median grain Cd BCF of 0.21) phenotypes in grain Cd accumulation, and this variability was labile to soil pH and the level of Cd stress. Wheat statistically had a higher root-to-shoot Cd-translocating ability than rice, highlighting potential food Cd risks and the importance of growing low-Cd wheat in slightly Cd-contaminated regions. Meanwhile, no correlations were detected among soil-to-root, root-to-shoot, and shoot-to-grain translocation factors, implying that Cd uptake and internal translocation in crops were probably controlled by different underlying gene tic mechanisms. Root-to-shoot Cd transport could be a favorable target trait for selecting and breeding low-Cd rice and wheat. In all, this review provides a comprehensive low-Cd crop list for remediation practice and a systematic meta-analysis inferring food Cd risks based on plant capacity for Cd accumulation and desired traits for low-Cd crop breeding.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB27040203)the National Natural Science Foundation of China (No.31770155)
文摘Epigenetics refers to the study of heritable changes in gene function that do not involve changes in the DNA sequence. Such effects on cellular and physiological phenotypic traits may result from external or environmental factors or be part of normal developmental program. In eukaryotes, DNA wraps on a histone octamer(two copies of H2A, H2B, H3 and H4) to form nucleosome, the fundamental unit of chromatin. The structure of chromatin is subjected to a dynamic regulation through multiple epigenetic mechanisms, including DNA methylation, histone posttranslational modifications(PTMs), chromatin remodeling and noncoding RNAs. As conserved regulatory mechanisms in gene expression, epigenetic mechanisms participate in almost all the important biological processes ranging from basal development to environmental response. Importantly, all of the major epigenetic mechanisms in mammalians also occur in plants. Plant studies have provided numerous important contributions to the epigenetic research. For example, gene imprinting, a mechanism of parental allele-specific gene expression, was firstly observed in maize; evidence of paramutation, an epigenetic phenomenon that one allele acts in a single locus to induce a heritable change in the other allele, was firstly reported in maize and tomato.Moreover, some unique epigenetic mechanisms have been evolved in plants. For example, the 24-nt siRNA-involved RNA-directed DNA methylation(RdDM) pathway is plant-specific because of the involvements of two plant-specific DNA-dependent RNA polymerases, Pol IV and Pol V. A thorough study of epigenetic mechanisms is of great significance to improve crop agronomic traits and environmental adaptability. In this review, we make a brief summary of important progress achieved in plant epigenetics field in China over the past several decades and give a brief outlook on future research prospects.We focus our review on DNA methylation and histone PTMs, the two most important aspects of epigenetic mechanisms.
基金supported by the grants from the National Natural Science Foundation of China (Nos.31071083 and 31130033)the National Science Foundation of USA (No.DBI 0922703)
文摘Plant centromeres are generally composed of tandem arrays of simple repeats that form a complex chromosome locus where the kinetochore forms and microtubules attach during mitosis and meiosis. Each chromosome has one centromere region, which is essential for accurate division of the genetic material. Recently, chromosomes containing two centromere regions （called dicentric chromosomes） have been found in maize and wheat. Interestingly, some dicentric chromosomes are stable because only one centromere is active and the other one is inactivated. Because such arrays maintain their typical structure for both active and inactive centromeres, the specification of centromere activity has an epigenetic component independent of the DNA sequence. Under some circumstances, the inactive centromeres may recover centromere function, which is called centromere reactivation. Recent studies have highlighted the important changes, such as DNA methylation and histone modification, that occur during centromere inactivation and reactivation.
基金funded by grants from the National Natural Science Foundation of China (31930006 to Y.W.)the National Key Research and Development Program of China (2022YFF1002903 to Y.W.)+1 种基金the Top Talents Program “One Case One Discussion”(Yishiyiyi to Y.W.)from Shandong provinceShandong Agricultural University Talent Introduction Start-up Fund (to N.Z.)
文摘Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicle or spike branches during the reproductive stage,respectively,both of which are significantly impacted by hormones and genetic factors.Tillering and panicle branching are closely interconnected and exhibit high environmental plasticity.Here,we summarize the recent progress in genetic,hormonal,and environmental factors regulation in the branching of rice and wheat.This review not only provides a comprehensive overview of the current knowledge on branching mechanisms in rice and wheat,but also explores the prospects for future research aimed at optimizing crop architecture for enhanced productivity.
基金supported by the National Natural Science Foundation of China(32070607)the National Key Research and Development Program of China(2020YFA0804000)the CAS Project for Young Scientists in Basic Research(YSBR-012).
文摘In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.
基金supported by the National Natural Science Foundation of China(No.41930651 and 41807013)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2020102)。
文摘Vegetation response to the combined effects of human and nature has raised extensive controversy.The relative contributions of ecological restoration and multiple climate factors on vegetation variation remain unclear.Combining spatial and temporal changes in fractional vegetation cover(FVC)and net primary productivity(NPP)from 2000 to 2021,we assessed the trend of these two indicators and quantified the impact of ecological restoration and climate factors on vegetation variation using partial correlation and residual analysis.The results indicated that:(1)From 2000 to 2021,vegetation restoration in the Taihang Mountain area was notably successful.FVC increased by 5.71%over 22 years with a change trend of 0.0018 per annum.The cumulative growth rate of NPP over the same period was 42.03%,corresponding to an average annual increase of 5.492 g(C)·m^(-2)·a^(-1).(2)During the 22-year period,the contribution rates of ecological engineering to FVC and NPP were 65.13%and 64.33%,respectively.Ecological restoration was the dominant factor affecting vegetation change,and its impact was increasing in over 90%of the regional projects.The primary climate controlling factor of NPP was precipitation,while FVC responded synergistically to precipitation(primary)and temperature(secondary).Overall,the impact of precipitation on vegetation was 1.5 times that of temperature.(3)Among various ecological restoration types,grassland restoration contributed the most to vegetation change,followed by forest land restoration.This study offers valuable scientific insights that can guide the sustainability of vegetation ecology in semi-arid mountainous areas.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,China(XDB1090000 to S.J.)the National Key Research and Development Program of China,China(2021YFF1000202 and 2022YFF1002903 to Y.L.).
文摘Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent studies in crops have uncovered numerous genes that control seed size and weight,many of which function by modulating phytohormone biosynthesis,metabolism,or signaling pathways.This review provides a comprehensive overview of the genetic and molecular mechanisms by which phytohormones regulate seed size and weight and their cross-talks in modulating seed size.We highlight the functional conservation and divergence of homologous genes that control seed size across species.A particular focus is placed on those genes that have promising potential for yield improvement.Finally,we discuss current challenges in phytohormone regulation of seed size and molecular design breeding strategies for translating this knowledge into crop improvement.
基金supported by the National Key Research and Development Program of China(2021YFD1200600)the National Natural Science Foundation of China(32272105).
文摘Powdery mildew is a serious disease caused by Blumeria graminis f.sp.tritici(Bgt)that critically threatens the yield and quality of wheat(Triticum aestivum L.).Using effective powdery mildew resistance genes is the optimal method for controlling this disease.Against the background of high genetic homogeneity among the modern commercial cultivars that are mainly derived from conventional interbreeding,the resistance genes from wheat relatives have especially prominent advantages.Octoploid triticale,produced from common wheat and rye(Secale cereale L.)through distant hybridization,is a new synthetic species and valuable gene donor for wheat improvement.In this study,we developed the wheat-rye line YT5 through the hybridization of octaploid triticale and two wheat lines.YT5 was confirmed to be a 6RL ditelosomic addition and 1R(1B)substitution line using genomic in situ hybridization(GISH),multicolor fluorescence in situ hybridization(mc-FISH),multicolor GISH(mc-GISH)and molecular marker analysis.Genetic analysis showed that the powdery mildew resistance in YT5 was derived from the rye chromosome arm 6RL.After inoculation with different Bgt isolates at the seedling stage,YT5 had compound reaction patterns with both obvious spores and hypersensitivity,and it gradually became highly resistant until the adult-plant stage,thus showing a resistance response significantly different from the reported Pm genes from rye chromosome 6RL.YT5 also showed promising agronomic performance,so it is expected to be an elite resistance donor for wheat improvement.To promote the transfer of the chromosome arm 6RL of YT5 in marker-assisted selection(MAS)breeding,we selected and verified two 6RL-specific kompetitive allelespecific PCR(KASP)markers that can be applied to efficiently detect this chromosome arm in different wheat backgrounds.
基金supported by the National Natural Science Foundation of China(32370435,62106080)the Hubei Provincial Natural Science Foundation of China(2024AFB566).
文摘For fast in-situ assessment of tiller phenotypes in rice breeding,we introduce the TillerPET model,an improved transformer-based deep learning solution that permits phenotyping the number and compactness of rice tillers in images of post-harvest rice stubble.A rice tiller phenotype dataset covering three years of field data and four experimental sites across China was constructed to train and validate the model.TillerPET reports an R2 of 0.941 for counting tiller number,demonstrating state-of-the-art performance on the proposed RTP dataset.Beyond its minimal errors in estimating tiller number,TillerPET also achieves an R2 of 0.978 for characterizing tiller compactness.The two phenotypic parameters exhibit a high degree of consistency with expert breeders,offering reliable phenotypic indicators to guide further breeding.
基金supported by the National Natural Science Foundation of China(32372116)to Yan He.
文摘Chromosomal DNA double-strand breaks(DSBs)are often generated in the genome of all living organisms.To combat DNA damage,organisms have evolved several DSB repair mechanisms,with nonhomologous end-joining(NHEJ)and homologous recombination(HR)being the two most prominent.Although two major pathways have been extensively studied in Arabidopsis,rice and other mammals,the exact functions and differences between the two DSB repair pathways in maize still remain less well understood.Here,we characterized mre11a and rad50,mutants of HR pathway patterns,which showed drastic degradation of the typically persistent embryo and endosperm during kernel development.Loss of MRE11 or RAD50 function led to chromosomal fragments and chromosomal bridges in anaphase.While we also reported that the NHEJ pathway patterns,KU70 and KU80 are associated with developmental growth and genome stability.ku70 and ku80 both displayed an obvious dwarf phenotype.Cytological analysis of the mutants revealed extensive chromosome fragmentation in metaphase and subsequent stages.Loss of KU70/80 function upregulated the expression of genes involved in cell cycle progression and nuclear division.These results provide insights into how NHEJ and HR are mechanistically executed during different plant developmental periods and highlight a competitive and complementary relationship between the NHEJ and HR pathways for DNA double-strand break repair in maize.
基金supported by grants from the Chinese Academy of Sciences(XDA24010101)the Biological Breeding-National Science and Technology Major Project(2024ZD04077)+2 种基金the National Key Research and Development Program of China(2023YFF1001200)Natural Science Foundation of Zhejiang Province(LD24C130001)the Agricultural Science and Technology Innovation Program(ASTIP)of CAAS。
文摘A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.
基金supported by grants from the Chinese Academy of Sciences(XDB39050800)the Major Project of Guangzhou National Laboratory(GZNL2024A03013)the National Natural Science Foundation of China(92357308 and 32321004)。
文摘The circadian clock is a highly hierarchical network of endogenous pacemakers that primarily maintains and directs oscillations through transcriptional and translational feedback loops,which modulates an approximately 24-h cycle of endocrine and metabolic rhythms within cells and tissues.While circadian clocks regulate metabolic processes and related physiology,emerging evidence indicates that metabolism and circadian rhythm are intimately intertwined.In this review,we highlight the concept of metabolites,including lipids and other polar metabolites generated from intestinal microbial metabolism and nutrient intake,as time cues that drive changes in circadian rhythms,which in turn influence metabolism and aging.Furthermore,we discuss the roles of functional metabolites as circadian cues,paving a new direction on potential intervention targets of circadian disruption,pathological aging,as well as metabolic diseases that are clinically important.
文摘Journal of Genetics and Genomics(JGG),launched in 1974,celebrates its 50th birthday in 2023.With continuous support from our authors,reviewers,readers,and the editorial board,JGG has made remarkable progress in the past year by publishing 122 papers covering major disciplines in life sciences and medical genetics with exciting discoveries.It is worthwhile to note that we have recruited 66 young talents to join JGG as junior editors,resulting in significant improvement in manuscript evaluation and journal promotion.Here,we summarize major progresses reported in JGG in 2023 fromaneditorial view.
文摘This erratum clarifies information in the article“Nucleolar histone deacetylases HDT1,HDT2,and HDT3 regulate plant reproductive development”by Luo et al.(2021).In the section on“Phenotype of hdt mutants”,the T-DNA insertional knockdown mutant for HDT2(hdt2,salk_1247_A02)should be“Sail_1247_A02”in the main text and Fig.3A.
文摘This erratum clarifies information in the Letter to the Editor“Actin polymerization induces mitochondrial distribution during collective cell migration”by Qu et al.(2023).In the section for the list of author names,“Chen Qu,Yating Kan,Hui Zuo,Mengqi Wu,Zhixiang Dong,Xinyi Wang,Qing Zhang,Heng Wang,Dou Wang,Jiong Chen”should be“Chen Qu,Yating Kan,Xinyi Wang,Hui Zuo,Mengqi Wu,Zhixiang Dong,Qing Zhang,Heng Wang,Dou Wang,Jiong Chen”.
基金supported by the ability establishment of sustainable use for valuable Chinese medicine resources(Grant No.2060302)the National Key R&D Program of China(Grant No.2018YFA0900603)+1 种基金the National Key R&D Program of China(Grant No.2020YFA0908000)the crosswise task based on DEYUANTANG pharmacy Co.,Ltd.Shanxi,China(Grant No.DYTKY180725).
文摘Safflower is an important oilseed crop that has been used in traditional Chinese medicine for thousands of years because of the clinically valuable flavonoid glycosides in its flower petals.However,the biosynthesis and molecular regulation of these compounds are still elusive due to the lack of a high-quality reference genome and scarce identification of key biosynthetic pathway genes in a medicinal safflower variety.Here we leveraged an integrative multi-omics strategy by combining genomic,comparative genomics,and tissue-specific transcriptome profiling with biochemical analysis to identify uridine diphosphate glycosyltransferases(UGTs)for flavonoid glycoside biosynthesis in safflower.We assembled and annotated a high-quality reference genome of a medicinal safflower variety,‘Yunhong3’.A comprehensive comparative genomic analysis indicated that an evolutionary whole-genome triplication event occurring in safflower contributed to gene amplification of the flavonoid biosynthetic pathway.By combining comparative transcriptome profiling with enzymatic reactions,we identified 11 novel UGTs that could catalyze the conversion of naringenin chalcone and phloretin to the corresponding O-glycosides.Moreover,we outlined the molecular pathway of hydroxysafflor yellow A(HSYA)biosynthesis featured by 17 newly identified UGTs with promising catalytic activity,laying the foundation for the synthetic production of HSYA.Our study reports systemic genome and gene expression information for flavonoid glycoside biosynthesis in medicinal safflower and provides insights into mechanisms regulating HSYA biosynthesis,which would facilitate the genetic improvement and synthetic bioengineering design for producing clinically valuable flavonoid glycosides in safflower.
基金supported by grants from Chinese Academy of Sciences (No. KSCX2-SW-304)the National Natural Science Foundation of China (No. 30521001)
文摘Abiotic stresses cause serious crop losses. Knowledge on genes functioning in plant responses to adverse growth conditions is essential for developing stress tolerant crops. Here we report that transgenic expression of MYB15, encoding a R2R3 MYB transcription factor in Arabidopsis thaliana, conferred hypersensitivity to exogenous abscisic acid （ABA） and improved tolerance to drought and salt stresses. The promoter of MYB15 was active in not only vegetative and reproductive organs but also the guard cells of stomata. Its transcript level was substantially upregulated by ABA, drought or salt treatments. Compared with wild type （WT） control, MYB15 overexpression lines were hypersensitive to ABA in germination assays, more susceptible to ABA-elicited inhibition of root elongation, and more sensitive to ABA-induced stomatal closure. In line with the above findings, the transcript levels of ABA biosynthesis （ABA1, ABA2）, signaling （AB13） and responsive genes （AtADH1, RD22, RD29B, AtEM6） were generally higher in MYB15 overexpression seedlings than in WT controls after treatment with ABA. MYB15 overexpression lines displayed improved survival and reduced water loss rates than WT control under water deficiency conditions. These overexpression lines also displayed higher tolerance to NaCI stress. Collectively, our data suggest that overexpression of MYB15 improves drought and salt tolerance in Arabidopsis possibly by enhancing the expression levels of the genes involved in ABA biosynthesis and signaling, and those encoding the stress-protective proteins.
基金Acknowledgments We are grateful to Dr Xinnian Dong （Duke University, Durham, NC, USA） for critical reading of the manuscript and valuable suggestions. We thank Dr Jianmin Zhou （National Institute of Biological Sciences, Beijing, China） for providing the fungus strain Botrytis cinerea, Dr Salome Prat （Institut de Biologia Molecular de Barcelona, Barcelona, Spain） for providing homozygous atmyc2-2 （T-DNA insertion line SALK_083483） seeds and Dr Daoxin Xie （Tsinghua University, Beijing, China） for providing the coil-I seeds. This work was supported by grants from The National Natural Science Foundation of China （30530440）, The Ministry of Science and Technology of China （2006CB 102004, 2006AA10A 116）, and The Chinese Academy of Sciences （KSCX2-YW-N-045）.
文摘Jasmonic acid （JA） is an important phytohormone that regulates plant defense responses against herbivore attack, pathogen infection and mechanical wounding. In this report, we provided biochemical and genetic evidence to show that the Arabidopsis thaliana NAC family proteins ANAC019 and ANAC055 might function as transcription activators to regulate JA-induced expression of defense genes. The role of the two NAC genes in JA signaling was examined with the anacO19 anac055 double mutant and with transgenic plants overexpressing ANACO19 or ANAC055. The anacO19 anac055 double mutant plants showed attenuated JA-induced VEGETATIVE STORAGE PROTEIN1 （VSP1） and LIPOXYGENASE2 （LOX2） expression, whereas transgenic plants overexpressing the two NAC genes showed enhanced JA-induced VSP1 and LOX2 expression. That the JA-induced expression of the two NAC genes depends on the function of COIl and AtMYC2, together with the finding that overexpression of ANACO19 partially rescued the JA-related phenotype of the atmyc2-2 mutant, has led us to a hypothesis that the two NAC proteins act downstream of AtMYC2 to regulate JA-signaled defense responses. Further evidence to substantiate this idea comes from the observation that the response of the anacO19 anac055 double mutant to a necrotrophic fungus showed high similarity to that of the atmyc2-2 mutant.
基金supported by the grant of the National High Technology Research and Development Program("863"Program)of China(No.2011AA100101)
文摘Thinopyrum elongatum （2n = 2x = 14, EE）, a wild relative of wheat, has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight （FHB）. In this study, a series of wheat （cv. Chinese Spring, CS） substitution and ditelosomic lines, including Th. elongatum additions, were assessed for Type II resistance to FHB. Results indicated that the lines containing chromosome 7E of Th. elongatum gave a high level of resistance to FHB, wherein the infection did not spread beyond the inoculated floret. Furthermore, it was determined that the novel resistance gene（s） of 7E was located on the short-ann （7ES） based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm. On the other hand, Th. elongatum chromosomes 5E and 6E likely contain gene（s） for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines. Genomic in situ hybridization （GISH） analysis revealed that the alien chromosomes in the addition and substitution lines were intact, and the lines did not contain discernible genomic aberrations. GISH and multicolor-GISH analyses were further performed on three trans- location lines that also showed high levels of resistance to FHB. Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th. elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E, while line TA3493 was found to contain one pair of wheat-Th, elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat. Thus, this study has established that the short-arm of chromosome 7E of Th. elongatum harbors gene（s） highly resistant to the spreading of FHB, and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance, implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.
基金We would like to thank Dr Nam-Hai Chua （Rockefeller Univer- sity） for kindly providing the pBA002Myc vector and the Arabi- dopsis Biological Resource Center （ABRC）, Ohio State University for providing ToDNA insertion lines. This work was supported by grants from National Natural Science Foundation of China （No. 30530400/90717006/30670195） to Q Xie and Y Wu, the Chinese Academy of Science （KSCX2-YW-N-010 and CXTD-S2005-2）, and the （iuangdong Natural Science Foundation, China （No. 5300648） to Z Deng.
文摘NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid （ABA）, methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses.
基金?nancially supported by the National Key Research and Development Program of China (No.2018YFD0800306)the Hebei Science Fund for Distinguished Young Scholars,China (No.D2018503005)
文摘In some densely-populated countries, farmland has been widely cadmium (Cd) contaminated, and the utilization of the contaminated farmland for crop production is currently unavoidable. This necessitates the use of low-Cd crops (i.e., pollution-safe cultivars, the crop varieties with the ability to accumulate a low level of Cd in their edible parts when grown on polluted soil) in these areas and highlights the importance of knowledge on phenotypic variation in crop Cd accumulation for food Cd risk control. Studies on phenotypic variation in heavy metal accumulation started decades ago for a wide range of crops, and synthesis of the scattered experimental results in the literature is in need. We built a Low-Cd Crops Database based on literature research, and relevant meta-analysis was performed to quantitatively explore the phenotypic variation in Cd uptake and translocation of rice and wheat. Considerable variability existed among rice (median grain Cd bioconce nt ration factor (BCF) of 0.10) and wheat (median grain Cd BCF of 0.21) phenotypes in grain Cd accumulation, and this variability was labile to soil pH and the level of Cd stress. Wheat statistically had a higher root-to-shoot Cd-translocating ability than rice, highlighting potential food Cd risks and the importance of growing low-Cd wheat in slightly Cd-contaminated regions. Meanwhile, no correlations were detected among soil-to-root, root-to-shoot, and shoot-to-grain translocation factors, implying that Cd uptake and internal translocation in crops were probably controlled by different underlying gene tic mechanisms. Root-to-shoot Cd transport could be a favorable target trait for selecting and breeding low-Cd rice and wheat. In all, this review provides a comprehensive low-Cd crop list for remediation practice and a systematic meta-analysis inferring food Cd risks based on plant capacity for Cd accumulation and desired traits for low-Cd crop breeding.
