Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmn...Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.展开更多
Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,wi...Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,with limited data on the synergistic effects and molecular mechanisms of combined OTMs(Fe,Cu,Mn,Zn)in growing-finishing pigs.Methods:This study aimed to investigate the effects of graded levels of micromineral proteinates(combined OTMs)on growth performance,mineral metabolism,and mRNA expression of mineral regulatory proteins.A total of 360 crossbred Duroc×Landrace×Large White pigs(initial body weight 47.1±4.8 kg)were randomly assigned to 6 dietary treatments:basal diet without microminerals(CON),basal diet with ITMs at commercially recommended levels(IT),and basal diets with 15%(OT 15%),25%(OT 25%),35%(OT 35%)commercially recommended levels(CRL)of combined micromineral proteinates.After a 70-day feeding trial,samples were analyzed using ICP-OES,ELISA,and RT-qPCR.Results:Results showed that reduced levels(15-35%CRL)of micromineral proteinates did not significantly affect average daily gain,average daily feed intake,or feed conversion ratio(gain-to-feed ratio)compared to IT(P>0.05),but significantly increased plasma Cu(1.73-1.83μg/mL)and Zn(1.72-1.97μg/mL)concentrations(P<0.05)and elevated activities of Cu/Zn-superoxide dismutase(32.9-35.9 U/L)and manganese superoxide dismutase(20.5-24.1 U/L)compared to CON(P<0.05),with no significant differences from IT(P>0.05).Fecal excretion of Fe,Cu,Mn,and Zn was significantly reduced by 35-50%in OT 15%-OT 35%groups compared to IT(P<0.05).OT 25%group exhibited the highest apparent absorptivity of Fe(38.5%),Cu(27.8%),and Zn(42.4%)(P<0.05),which was associated with significantly regulated mRNA expression of mineral regulatory proteins:upregulated DMT1,FPN1,ZIP4,and MT1A in the duodenum,and modulated HAMP,ATP7B,ZIP14,and ZnT1 in the liver(P<0.05).Conclusion:In conclusion,dietary supplementation with 25%CRL or less of combined micromineral proteinates can fully meet the nutritional needs of growing-finishing pigs,improve mineral absorptivity,and reduce fecal mineral excretion by regulating intestinal and hepatic mineral transport and homeostatic proteins,providing a sustainable alternative to high-dose ITMs.展开更多
Multienzyme cascades enable the sequential synthesis of complex chemicals by combining multiple catalytic processes in one pot,offering considerable time and cost savings compared to a series of separate batch reactio...Multienzyme cascades enable the sequential synthesis of complex chemicals by combining multiple catalytic processes in one pot,offering considerable time and cost savings compared to a series of separate batch reactions.However,challenges related to coordination and regulatory interplay among multiple enzymes reduce the catalytic efficiency of such cascades.Herein,we genetically programmed a scaffold framework that selectively and orthogonally recruits enzymes as designed.The system was then used to generate multienzyme complexes of D-allulose 3-epimerase(DAE),ribitol dehydrogenase(RDH),and formate dehydrogenase(FDH)for rare sugar production.This scaffolded multienzymatic assembly achieves a 10.4-fold enhancement in the catalytic performance compared to its unassembled counterparts,obtaining allitol yield of more than 95%.Molecular dynamics simulations revealed that shorter distances between neighboring enzymes in scaffold-mounted complexes facilitated the transfer of reaction intermediates.A dual-module catalytic system incorporating(1)scaffold-bound complexes of DAE,RDH,and FDH and(2)scaffold-bound complexes of alcohol dehydrogenase and NADH oxidase expressed intracellularly in E.coli was used to synthesize D-allulose from D-fructose.This system synthesized 90.6%D-allulose from 300 g L^(−1)D-fructose,with a space-time yield of 13.6 g L^(−1)h^(−1).Our work demonstrates the programmability and versatility of scaffold-based strategies for the advancement of multienzyme cascades.展开更多
<span style="font-family:;" "=""><span style="font-family:Verdana;">Methane production by archaea depends on tetrahydromethanopterin (H</span><sub><span st...<span style="font-family:;" "=""><span style="font-family:Verdana;">Methane production by archaea depends on tetrahydromethanopterin (H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT), a pterin-containing cofactor that carries one-carbon units. Two redox reactions within the nine steps of H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT side chain biosynthesis have been hypothesized. Biochemical assays have demonstrated that the archaeal iron-sulfur flavoprotein dihydromethanopterin reductase X (DmrX or MM1854) catalyzes the final reaction of the pathway, the reduction of dihydromethanopterin to H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> using dithiothreitol (DTT) as an artificial electron donor. The crystal structure of DmrB, a bacterial DmrX homolog that lacks iron-sulfur clusters, has led to a proposed ping-pong mechanism of electron transfer between FMNH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and the FMN prosthetic group of DmrB. However, an enzymatic assay to test the hypothetical DmrB mechanism is lacking because a suitable electron donor has not previously been identified. Furthermore, a second uncharacterized archaeal flavoprotein (MM1853) has been hypothesized to function in H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT side chain biosynthesis. In this </span><span style="font-family:Verdana;">work, to facilitate the development of assays to elucidate the functions of DmrB </span><span style="font-family:Verdana;">and MM1853, we tested a variety of electron donors, including dithiothreitol, ferredoxin, and a system consisting of NADH and an NADH-dependent fla</span><span style="font-family:Verdana;">vin-reducing enzyme (Fre).</span><span style="font-family:Verdana;"> Reduction of the DmrB prosthetic group (FMN) was measured as a decrease in absorbance at 460 nm. NADPH, NADH, and </span><span style="font-family:Verdana;">DTT were unable to reduce DmrB. However, NADH/Fre was able to reduce </span><span style="font-family:Verdana;">DmrB within 70 min (initial rate of 1.3 μM/min), providing the basis for a future DmrB activity assay. Carbon monoxide (CO)/CO dehydrogenase/ferredoxin reduced DmrB more rapidly within 6 min. Both electr</span><span style="font-family:Verdana;">on transfer systems reduced a second flavin-containing archaeal protein MM1853, which is predicted to catalyze the third step of H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT biosynthesis. While NADH and NADPH were incapable of directly reducing the FMN cofactor of MM1853, DTT or NADH/Fre could eliminate the FMN peaks. These results establish the basis for new oxidoreductase assays that will facilitate testing several proposed DmrB mechanisms and defining the specific function of MM1853 in methanogen cofactor biosynthesis.</span></span>展开更多
Our previous studies showed a predominance of high molecular weight protein group in tumor nuclear matrices. Contrary to normal cells, proteins of this group are preferentially phosphorylated. Phosphoproteins of hepat...Our previous studies showed a predominance of high molecular weight protein group in tumor nuclear matrices. Contrary to normal cells, proteins of this group are preferentially phosphorylated. Phosphoproteins of hepatoma nuclear matrix are selectively subjected to rapid proteolysis. By alkali treatment and a monoclonal antibody against phosphotyrosyl residue the presence of two high molecular weight bands of phosphotyrosyl-containing proteins was detected in nuclear matrices of tumor but not of normal liver cells. High molecular weight protein group of tumor nuclear matrices revealed also a rapid turnover and preferential incorporation of labeled amino acids selectively inhibited by chloramphenicol.展开更多
Chitin is an abundant aminopolysaccharide found in insect pests and phytopathogenic microorganisms but absent in higher plants and vertebrates. It is crucial for mitigating threats posed by chitin-containing organisms...Chitin is an abundant aminopolysaccharide found in insect pests and phytopathogenic microorganisms but absent in higher plants and vertebrates. It is crucial for mitigating threats posed by chitin-containing organisms to human health, food safety, and agriculture. Therefore, targeting the chitin biosynthesisassociated bioprocess holds a promise for developing human-safe and eco-friendly antifungal agents or pesticides. Chitin biosynthesis requires chitin synthase and associated factors, which are involved in the modification, regulation, organization or turnover of chitin during its biosynthesis. A number of enzymes such as chitinases, hexosaminidases, chitin deacetylases are closely related and therefore are promising targets for designing novel agrochemicals that target at chitin biosynthesis. This review summarizes the advances in understanding chitin biology over the past decade by our research group and collaborates,specifically regarding essential proteins linked to chitin biosynthesis that can be exploited as promising pesticide targets. Examples of small bioactive molecules that against the activity of these targets are given.展开更多
Xylo-oligosaccharides(XOSs)are a category of functional oligosaccharides primarily composed of 2-7 xylose units linked byβ-1,4 glycosidic bonds.They are recognized as soluble dietary fibers with prebiotic properties....Xylo-oligosaccharides(XOSs)are a category of functional oligosaccharides primarily composed of 2-7 xylose units linked byβ-1,4 glycosidic bonds.They are recognized as soluble dietary fibers with prebiotic properties.Recently, there has been significant interest in manufacturing XOSs from xylan extracted from lignocellulosic biomass using enzyme catalysis under mild conditions. In this work, the arabinofuranosidase Abf62A gene was cloned from Aspergillus usamii genomic DNA through sequential molecular processes and expressed in Pichia pastoris X33. The xylan (100 g/L) extracted xylan in wheat straw (WS) was biologically hydrolyzed into 50.32 g/L of XOSs by xylanase Xyn11A (300 U/g substrate) and arabinofuranase Abf62A (20 U/g substrate), which indicated a notable synergistic effect compared to the 34.42 g/L XOSs produced via Xyn11A. The 50.32 g/L of XOSs products comprised xylobiose (31.71 g/L), xylotriose (15.92 g/L), xylotetraose (1.65 g/L) and xylopentaose (1.04 g/L). Notably, the combined content of xylobiose and xylotriose accounted for up to 94.7%. The XOSs purified from the enzyme hydrolysate could effectually scavenge free radicals, and the antioxidant activity was more than 90%. In summary, XOSs were biologically manufactured from wheat straw xylan through the synergistic biocatalysis via xylanase and arabinofuranosidase Abf62A in a green and sustainable way, rending one kind of prebiotic oligosaccharides with substantial positive effects on human and animal health.展开更多
Objective To investigate effect of inhibiting melatonin biosynthesis on activities of protein kinase A (PKA), glycogen synthase kinase-3 (GSK-3) and tau phosphorylation at PS214 and M4 epitopes using haloperidol, a sp...Objective To investigate effect of inhibiting melatonin biosynthesis on activities of protein kinase A (PKA), glycogen synthase kinase-3 (GSK-3) and tau phosphorylation at PS214 and M4 epitopes using haloperidol, a specific inhibitor of 5-hydroxyindole-O-methyltransferase. Methods Brain ventricular and intraperitoneal injections were used for haloperidol administration, Western blots for tau phosphorylation, 32P-labeling for PKA and GSK-3 activity, and high performance liquid chromatograph for detection of serum melatonin levels. Results Haloperidol injection through the lateral ventricle and intraperitoneal reinforcement significantly stimulated PKA activity with a concurrent hyperphosphorylation of tau at M4 (Thr231/Ser235) and PS214 (Ser214) sites. Prior treatment of the rats using melatonin supplement for one week and reinforcement during the haloperidol administration arrested PKA activity and attenuated tau hyperphosphorylation. GSK-3 activity showed no obvious change after haloperidol injection, however, melatonin supplements and reinforcements during haloperidol infusion inactivated basal activity of GSK-3. Conclusion Decreased melatonin may be involved in Alzheimer-like tau hyperphosphorylation, and overactivation of PKA may play a crucial role in this process.展开更多
Selenocysteine (Sec) tRNAs serve as carrier molecules for the biosynthesis of Sec from serine and to donate Sec to protein in response to specific UGA codons. In this study, we describe the current status of Sec tRNAs...Selenocysteine (Sec) tRNAs serve as carrier molecules for the biosynthesis of Sec from serine and to donate Sec to protein in response to specific UGA codons. In this study, we describe the current status of Sec tRNAs in higher animals and further we exarnine: (i) the Sec tRNA population in Drosophila; (ii) transcription of the Sec tRNA in vivo (in Xenopus oocytes) and in vitro (in Xenopus oocyte extracts); (iii) the effect of selenium on the Sec tRNA population in various rat tissues following replenishment of extremely selenium deficient rats with this element; and (iv) the biosynthesis of the modified bases on Sec tRNA in Xenopus oocytes展开更多
Background Post-weaning diarrhea(PWD)in piglets,often caused by F4^(+)enterotoxigenic Escherichia coli(ETEC),poses significant challenges in pig production.Traditional solutions like antibiotics and zinc oxide face in...Background Post-weaning diarrhea(PWD)in piglets,often caused by F4^(+)enterotoxigenic Escherichia coli(ETEC),poses significant challenges in pig production.Traditional solutions like antibiotics and zinc oxide face increasing restrictions due to growing concerns over antibiotic resistance and environmental sustainability.This study investigates the application of bivalent heavy chain variable domain(V_(H)H)constructs(BL1.2 and BL2.2)targeting ETEC virulence factors,administered in feed to mitigate ETEC-induced PWD in weaned piglets.Results The supplementation of BL1.2 and BL2.2 in both mash and pelleted feed significantly reduced the diarrhea incidence and fecal shedding of F4^(+)ETEC in challenged piglets.Pelleted feed containing V_(H)H constructs helped to preserve gut barrier integrity by maintaining levels of the tight junction protein occludin in the small intestine.Additionally,the constructs maintained blood granulocyte counts at a similar level to the non-challenged control group,including neutrophils,and ameliorated the acute phase protein response after challenge.Notably,even at low feed intake immediately after weaning,V_(H)H constructs helped maintain piglet health by mitigating ETEC-induced inflammation and the resulting diarrhea.Conclusions Our findings demonstrated that using V_(H)H constructs as feed additives could serve as an effective strategy to help manage ETEC-associated PWD,by reducing F4^(+)ETEC gut colonization and supporting gut barrier function of weaned piglets.The high stability of these V_(H)H constructs supports their incorporation into industrial feed manufacturing processes,offering a more sustainable preventive strategy compared to traditional antimicrobial interventions,which could contribute to sustainable farming practices.展开更多
The present study was carried out to evaluate the pollution and its effect on the quality of catfish. Four sites in Eygpt were chosen for the research, Ras El-Bar (Site 1) as control, Shatta (Site 2), Kafr El-Bateekh ...The present study was carried out to evaluate the pollution and its effect on the quality of catfish. Four sites in Eygpt were chosen for the research, Ras El-Bar (Site 1) as control, Shatta (Site 2), Kafr El-Bateekh (Site 3), and Talkha (Site 4). The research was carried out on water, sediments and catfish (serum and muscles). Nitrite, nitrate and ammonia were determined in water and sediment. Also, RNA and DNA were determined in serum samples and the muscles of the catfish. In addition, the concentrations of heavy metals (Pb, Cd, Fe, Zn and Cu) were estimated in water, sediments and the muscles of catfish. Also, hepatosomatic index, liver water content, condition factor, lipid and protein contents were determined in the fish. The concentrations of nitrite, nitrate and ammonia in water and sediment of Site 4 and the levels of heavy metals especially Pb and Cd in water, sediment and muscle of catfish from Sites 3 and 4 were highly elevated compared to those of the control. On the other hand, DNA, RNA and protein contents in the catfish of Sites 3 and 4 decreased. The results illustrated that, Cd and Pb levels in the muscle of catfish were negatively correlated with DNA, RNA and with the protein contents. In conclusion, the accumulation of heavy metals in catfish tissues therefore, can cause health problems in human after catfish intake.展开更多
Cyclocarya paliurus(Batalin)Iljinskaja,as a unique and rare monocotyledonous plant in Southern China,is a promising and economical Chinese herbal medicine and functional food.People have conducted a number of research...Cyclocarya paliurus(Batalin)Iljinskaja,as a unique and rare monocotyledonous plant in Southern China,is a promising and economical Chinese herbal medicine and functional food.People have conducted a number of research on C.paliurus because of its rich triterpenoids.However,no comprehensive review has illustrated the composition and pharmacological activity of triterpenoids from C.paliurus.This review summarizes 177 triterpenoids from different parts of C.paliurus.The structures of compounds were elucidated,and their biosynthesis was inferred.The biological activities of compounds and triterpenoid-rich extracts,including anti-diabetes,antihyperlipidemia,anti-inflammatory,anticancer or cytotoxicity,antioxidation,etc.,were discussed.C.paliurus can be an important and valuable supplement to the food market.This review provides a reference for the further research and application of C.paliurus triterpenoids in the fields of foods and pharmaceuticals.展开更多
The surface macromolecules of probiotic bacteria play crucial roles in modulating immune responses in the host.Exopolysaccharide(EPS)from lactic acid bacteria(LAB)have been widely reported to exhibit immunomodulatory ...The surface macromolecules of probiotic bacteria play crucial roles in modulating immune responses in the host.Exopolysaccharide(EPS)from lactic acid bacteria(LAB)have been widely reported to exhibit immunomodulatory activity.In this study,the EPS biosynthesis gene cluster of Lacticaseibacillus paracasei S-NB was analyzed and a deletion mutant S-NBΔ7576(two genes S-NB_2175/wze and S-NB_2176/wzd were responsible for the chain length determination and export of EPS)was successfully constructed,resulting a 40.02%decrease in the production of EPS.The deletion of wze and wzd had little effect on the monosaccharide composition and major groups of the two EPS fractions(BEPS1 and BEPS2).Both BEPS1 and BEPS2 could inhibit the transcriptional level of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),inducible nitric oxide synthase(i NOS)and cyclooxygenase-2(COX-2)mRNA in RAW 264.7 cells induced by lipopolysaccharide(LPS),and enhance host immune tolerance via suppressing NF-κB and MAPK signaling.Notably,the S-NBΔ7576 mutant supplied with the BEPS1/BEPS2 exhibited more significant inhibition of cytokines production and the phosphorylation of p65 and c-Jun N-terminal kinase(JNK)in LPS-stimulated cells compared with the S-NBΔ7576 mutant alone.Our study provided the immunomodulatory effect of BEPS1 and BEPS2 from L.paracasei S-NB,in which the wze and wzd genes associated with EPS biosynthesis may play an important role.展开更多
The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval ...The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval at the B1 locus on chromosome 5A,which included the candidate gene encoding a zinc finger protein(TraesCS5A01G542800)as an awn length inhibitor(ALI).The Ali-A1 allele for the awnless trait showed abundant sequence differences in the promoter regions compared to the ali-A1 allele for the long-awn trait.The results of the swap experiment on the promoters from the two ALI-A1 alleles showed that the two promoters caused a difference in the protein level,indicating the gene was regulated at the transcript level.However,the ali-A1 allele contained an SNP that caused a premature stop codon in its coding region,resulting in a truncated protein compared to the functional Ali-A1 protein.The Ali-A1 protein contained two ethylene-responsive element binding factor-associated amphiphilic repression(EAR)motifs,one at the N terminus(EAR-N)and the other at the C terminus(EAR-C),and they were involved in interactions with the wheat co-repressor protein TOPLESS(TPL1).The ali-A1 protein retained the EAR-N motif but lost the EAR-C motif,resulting in the attenuated ability to interact with TPL1.The tpl1 mutant produced a longer awn compared to the wild type.Ali-A1 repressed the transcription of two downstream genes,TaLRP-A1 and TaARF-B1,involved in endogenous auxin concentrations and auxin responses in wheat.We concluded that the awn length is regulated not only by the ALI-A1 gene at transcript levels but also by Ali-A1 and TPL1 at the protein level in wheat.展开更多
Mammalian scent glands mediate species-specific chemical communication,yet the mechanistic basis for convergent musk production remain incompletely understood.Forest musk deer and muskrat have independently evolved sp...Mammalian scent glands mediate species-specific chemical communication,yet the mechanistic basis for convergent musk production remain incompletely understood.Forest musk deer and muskrat have independently evolved specialized musk-secreting glands,representing a striking case of convergent evolution.Through an integrated multi-omics approach,this study identified cyclopentadecanone as a shared key metabolic precursor in musk from both forest musk deer and muskrat,although downstream metabolite profiles diverged between the two lineages.Single-cell RNA sequencing revealed that these specialized apocrine glands possessed unique secretory architecture and exhibited transcriptional profiles associated with periodic musk production,distinct from those in conventional apocrine glands.Convergent features were evident at the cellular level,where acinar,ductal,and basal epithelial subtypes showed parallel molecular signatures across both taxa.Notably,acinar cells in both species expressed common genes involved in fatty acid and glycerolipid metabolism(e.g.,ACSBG1,HSD17B12,HACD2,and HADHA),suggesting a conserved molecular framework for musk precursor biosynthesis.Metagenomic analysis of musk samples further revealed parallel microbial community structures dominated by Corynebacterium and enriched in lipid metabolic pathways.These findings suggest multi-level convergence in musk biosynthesis,from molecular pathways to microbial communities,providing novel insights into mammalian chemical signaling and artificial musk production.展开更多
In plants, transcription factor (TF) family LATERAL ORGAN BOUNDARIES DOMAIN (LBD) has been identified to be involved in the ripening and senescence processes of fruits. However, the function of LBD in Hylocereus undat...In plants, transcription factor (TF) family LATERAL ORGAN BOUNDARIES DOMAIN (LBD) has been identified to be involved in the ripening and senescence processes of fruits. However, the function of LBD in Hylocereus undatus (Haw.) Britton & Rose (H. undatus) has not been reported yet. Through transcriptomic analysis, virus-induced gene silencing (VIGS) technology, and RT-qPCR validation, we investigated the role of the LBD TFs in the senescence of H. undatus. Transcriptomic analysis revealed that HuLBD1 is a key transcription factor of the LBD family regulating H. undatus senescence. After silencing HuLBD1, 5075 differentially expressed genes (DEGs) were identified. GSEA results showed that these DEGs were mainly enriched in the phenylpropanoids and flavonoid biosynthesis pathway. The leading subset of genes in these two pathways included 16 DEGs, with four upregulated genes, HuCHS1-2, HuFLS1, HuCYP75B2, and HuCHS5-2 being central in the Protein-Protein Interaction (PPI) network. H. undatus phenotypic experiments confirmed that silencing HuLBD1 significantly increased the flavonoid content in the fruit peel, and RT-qPCR validation showed that the gene expression trends were consistent with the RNA-seq data. The study indicated that HuLBD1 likely delays the fruit senescence process by negatively regulating the expression of four key genes, including HuCHS1-2, thus promoting the synthesis of phenylpropanoids such as flavonoids. In conclusion, our findings suggest that the HuLBD1 TF plays an important role in the senescence of H. undatus fruit, providing a theoretical basis for postharvest senescence control.展开更多
Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increas...Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increased fundamental knowledge on starch biosynthesis,development of advanced breeding strategies,efficient farming,and well-adapted and up scalable extraction protocols for diverse starch products.Recent staggering progress in molecular breeding techniques,especially genome editing,have enabled generation of higher starch yield and special functional qualities required to support such advancement.However,this necessitates fundamental biochemical and mechanistic understanding of starch biosynthesis and the variegated starch crop germplasms,all of which are closely linked to the relationships between starch molecular structures and functionality of various starch types as directed by the different capabilities of starch crop genotypes.We here review starch biosynthesis and its genetic foundation with a focus on increasing nutritional and health-promoting value of starch especially through bioengineering of the high amylose trait.展开更多
In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and en...In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and environmental risks.In this study,a novel biosynthesis strategy was developed to fabricate fluorescent cellulose by adding fluorescent glucose derivatives to a bacterial fermentation broth.The metabolic activity of bacteria is utilized to achieve in situ polymerization of glucose and its derivatives during the synthesis of bacterial cellulose.Owing to the structural similarity between triphenylamine-modified glucose(TPA-Glc N)and glucose monomers,the TPA-Glc N were efficiently assimilated by the bacterial cells and incorporated into the cellulose matrix,resulting in a uniform distribution of fluorescence.The fluorescence color and intensity of the obtained cellulose could be adjusted by varying the amount of the fluorescent glucose derivatives.Compared to the fluorescent cellulose synthesized through physical dyeing,the fluorescence of the products obtained by in situ polymerization showed higher intensity and stability.Furthermore,fluorescent bacterial cellulose can be hydrolyzed into nanocellulose-based ink,which demonstrates exceptional anti-counterfeiting capabilities under UV light.This biosynthesis method not only overcomes the limitations of traditional modification techniques but also highlights the potential of microbial systems as platforms for synthesizing functional polymers.展开更多
A category of highly fused diterpenoid natural products possessing a characteristic perhydropyrene-like or rearranged tetracyclic skeleton structure are distributed in different life forms.Compared to traditional poly...A category of highly fused diterpenoid natural products possessing a characteristic perhydropyrene-like or rearranged tetracyclic skeleton structure are distributed in different life forms.Compared to traditional polycyclic diterpenoids,their biosynthetic pathways are quite unique and diverse.Chemists have pinpointed a range of this type of unusual diterpenoids:cycloamphilectanes and isocycloamphilectanes,kempenes and rippertanes,hydropyrene and hydropyrenol,along with recently disclosed cephalotanes.This review describes developments in this field and discusses the challenges associated with synthesizing this class of highly complex compounds.展开更多
The black wolfberry(Lycium ruthenicum;2n=2x=24)is an important medicinal plant with ecological and economic value.Its fruits have numerous beneficial pharmacological activities,especially those of anthocyanins,polysac...The black wolfberry(Lycium ruthenicum;2n=2x=24)is an important medicinal plant with ecological and economic value.Its fruits have numerous beneficial pharmacological activities,especially those of anthocyanins,polysaccharides,and alkaloids,and have high nutritional value.However,the lack of available genomic resources for this species has hindered research on its medicinal and evolutionary mechanisms.In this study,we developed the telomere-to-telomere(T2T)nearly gapless genome of L.ruthenicum(2.26 Gb)by integrating PacBio HiFi,Nanopore Ultra-Long,and Hi-C technologies.The assembled genome comprised 12 chromosomes with 37,149 protein-coding genes functionally annotated.Approximately 80%of the repetitive sequences were identified,of which long terminal repeats(LTRs)were the most abundant,accounting for 73.01%.The abundance of LTRs might be the main reason for the larger genome of this species compared to that of other Lycium species.The species-specific genes of L.ruthenicum were related to defense mechanisms,salt tolerance,drought resistance,and oxidative stress,further demonstrating their superior adaptability to arid environments.Based on the assembled genome and fruit transcriptome data,we further constructed an anthocyanin biosynthesis pathway and identified 19 candidate structural genes and seven transcription factors that regulate anthocyanin biosynthesis in the fruit developmental stage of L.ruthenicum,most of which were highly expressed at a later stage in fruit development.Furthermore,154 potential disease resistance-related nucleotidebinding genes have been identified in the L.ruthenicum genome.The whole-genome and proximal,dispersed,and tandem duplication genes in the L.ruthenicum genome enriched the number of genes involved in anthocyanin synthesis and resistance-related pathways.These results provide an important genetic basis for understanding genome evolution and biosynthesis of pharmacologically active components in the Lycium genus.展开更多
文摘Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.
基金financially supported by the Hainan Province Science and Technology Special Fund(Grant no:ZDYF2024XDNY187).
文摘Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,with limited data on the synergistic effects and molecular mechanisms of combined OTMs(Fe,Cu,Mn,Zn)in growing-finishing pigs.Methods:This study aimed to investigate the effects of graded levels of micromineral proteinates(combined OTMs)on growth performance,mineral metabolism,and mRNA expression of mineral regulatory proteins.A total of 360 crossbred Duroc×Landrace×Large White pigs(initial body weight 47.1±4.8 kg)were randomly assigned to 6 dietary treatments:basal diet without microminerals(CON),basal diet with ITMs at commercially recommended levels(IT),and basal diets with 15%(OT 15%),25%(OT 25%),35%(OT 35%)commercially recommended levels(CRL)of combined micromineral proteinates.After a 70-day feeding trial,samples were analyzed using ICP-OES,ELISA,and RT-qPCR.Results:Results showed that reduced levels(15-35%CRL)of micromineral proteinates did not significantly affect average daily gain,average daily feed intake,or feed conversion ratio(gain-to-feed ratio)compared to IT(P>0.05),but significantly increased plasma Cu(1.73-1.83μg/mL)and Zn(1.72-1.97μg/mL)concentrations(P<0.05)and elevated activities of Cu/Zn-superoxide dismutase(32.9-35.9 U/L)and manganese superoxide dismutase(20.5-24.1 U/L)compared to CON(P<0.05),with no significant differences from IT(P>0.05).Fecal excretion of Fe,Cu,Mn,and Zn was significantly reduced by 35-50%in OT 15%-OT 35%groups compared to IT(P<0.05).OT 25%group exhibited the highest apparent absorptivity of Fe(38.5%),Cu(27.8%),and Zn(42.4%)(P<0.05),which was associated with significantly regulated mRNA expression of mineral regulatory proteins:upregulated DMT1,FPN1,ZIP4,and MT1A in the duodenum,and modulated HAMP,ATP7B,ZIP14,and ZnT1 in the liver(P<0.05).Conclusion:In conclusion,dietary supplementation with 25%CRL or less of combined micromineral proteinates can fully meet the nutritional needs of growing-finishing pigs,improve mineral absorptivity,and reduce fecal mineral excretion by regulating intestinal and hepatic mineral transport and homeostatic proteins,providing a sustainable alternative to high-dose ITMs.
文摘Multienzyme cascades enable the sequential synthesis of complex chemicals by combining multiple catalytic processes in one pot,offering considerable time and cost savings compared to a series of separate batch reactions.However,challenges related to coordination and regulatory interplay among multiple enzymes reduce the catalytic efficiency of such cascades.Herein,we genetically programmed a scaffold framework that selectively and orthogonally recruits enzymes as designed.The system was then used to generate multienzyme complexes of D-allulose 3-epimerase(DAE),ribitol dehydrogenase(RDH),and formate dehydrogenase(FDH)for rare sugar production.This scaffolded multienzymatic assembly achieves a 10.4-fold enhancement in the catalytic performance compared to its unassembled counterparts,obtaining allitol yield of more than 95%.Molecular dynamics simulations revealed that shorter distances between neighboring enzymes in scaffold-mounted complexes facilitated the transfer of reaction intermediates.A dual-module catalytic system incorporating(1)scaffold-bound complexes of DAE,RDH,and FDH and(2)scaffold-bound complexes of alcohol dehydrogenase and NADH oxidase expressed intracellularly in E.coli was used to synthesize D-allulose from D-fructose.This system synthesized 90.6%D-allulose from 300 g L^(−1)D-fructose,with a space-time yield of 13.6 g L^(−1)h^(−1).Our work demonstrates the programmability and versatility of scaffold-based strategies for the advancement of multienzyme cascades.
文摘<span style="font-family:;" "=""><span style="font-family:Verdana;">Methane production by archaea depends on tetrahydromethanopterin (H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT), a pterin-containing cofactor that carries one-carbon units. Two redox reactions within the nine steps of H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT side chain biosynthesis have been hypothesized. Biochemical assays have demonstrated that the archaeal iron-sulfur flavoprotein dihydromethanopterin reductase X (DmrX or MM1854) catalyzes the final reaction of the pathway, the reduction of dihydromethanopterin to H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> using dithiothreitol (DTT) as an artificial electron donor. The crystal structure of DmrB, a bacterial DmrX homolog that lacks iron-sulfur clusters, has led to a proposed ping-pong mechanism of electron transfer between FMNH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and the FMN prosthetic group of DmrB. However, an enzymatic assay to test the hypothetical DmrB mechanism is lacking because a suitable electron donor has not previously been identified. Furthermore, a second uncharacterized archaeal flavoprotein (MM1853) has been hypothesized to function in H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT side chain biosynthesis. In this </span><span style="font-family:Verdana;">work, to facilitate the development of assays to elucidate the functions of DmrB </span><span style="font-family:Verdana;">and MM1853, we tested a variety of electron donors, including dithiothreitol, ferredoxin, and a system consisting of NADH and an NADH-dependent fla</span><span style="font-family:Verdana;">vin-reducing enzyme (Fre).</span><span style="font-family:Verdana;"> Reduction of the DmrB prosthetic group (FMN) was measured as a decrease in absorbance at 460 nm. NADPH, NADH, and </span><span style="font-family:Verdana;">DTT were unable to reduce DmrB. However, NADH/Fre was able to reduce </span><span style="font-family:Verdana;">DmrB within 70 min (initial rate of 1.3 μM/min), providing the basis for a future DmrB activity assay. Carbon monoxide (CO)/CO dehydrogenase/ferredoxin reduced DmrB more rapidly within 6 min. Both electr</span><span style="font-family:Verdana;">on transfer systems reduced a second flavin-containing archaeal protein MM1853, which is predicted to catalyze the third step of H</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">MPT biosynthesis. While NADH and NADPH were incapable of directly reducing the FMN cofactor of MM1853, DTT or NADH/Fre could eliminate the FMN peaks. These results establish the basis for new oxidoreductase assays that will facilitate testing several proposed DmrB mechanisms and defining the specific function of MM1853 in methanogen cofactor biosynthesis.</span></span>
文摘Our previous studies showed a predominance of high molecular weight protein group in tumor nuclear matrices. Contrary to normal cells, proteins of this group are preferentially phosphorylated. Phosphoproteins of hepatoma nuclear matrix are selectively subjected to rapid proteolysis. By alkali treatment and a monoclonal antibody against phosphotyrosyl residue the presence of two high molecular weight bands of phosphotyrosyl-containing proteins was detected in nuclear matrices of tumor but not of normal liver cells. High molecular weight protein group of tumor nuclear matrices revealed also a rapid turnover and preferential incorporation of labeled amino acids selectively inhibited by chloramphenicol.
基金supported by the National Key Research and Development Program of China (No. 2022YFD1700200)the National Natural Science Foundation of China (Nos. 32161133010, 3230170969)+1 种基金the Innovation Program of Chinese Academy of Agricultural Sciences, the Shenzhen Science and Technology Program (No. KQTD20180411143628272)the Special Funds for Science Technology Innovation and Industrial Development of Shenzhen Dapeng New District (No. PT202101–02)。
文摘Chitin is an abundant aminopolysaccharide found in insect pests and phytopathogenic microorganisms but absent in higher plants and vertebrates. It is crucial for mitigating threats posed by chitin-containing organisms to human health, food safety, and agriculture. Therefore, targeting the chitin biosynthesisassociated bioprocess holds a promise for developing human-safe and eco-friendly antifungal agents or pesticides. Chitin biosynthesis requires chitin synthase and associated factors, which are involved in the modification, regulation, organization or turnover of chitin during its biosynthesis. A number of enzymes such as chitinases, hexosaminidases, chitin deacetylases are closely related and therefore are promising targets for designing novel agrochemicals that target at chitin biosynthesis. This review summarizes the advances in understanding chitin biology over the past decade by our research group and collaborates,specifically regarding essential proteins linked to chitin biosynthesis that can be exploited as promising pesticide targets. Examples of small bioactive molecules that against the activity of these targets are given.
文摘Xylo-oligosaccharides(XOSs)are a category of functional oligosaccharides primarily composed of 2-7 xylose units linked byβ-1,4 glycosidic bonds.They are recognized as soluble dietary fibers with prebiotic properties.Recently, there has been significant interest in manufacturing XOSs from xylan extracted from lignocellulosic biomass using enzyme catalysis under mild conditions. In this work, the arabinofuranosidase Abf62A gene was cloned from Aspergillus usamii genomic DNA through sequential molecular processes and expressed in Pichia pastoris X33. The xylan (100 g/L) extracted xylan in wheat straw (WS) was biologically hydrolyzed into 50.32 g/L of XOSs by xylanase Xyn11A (300 U/g substrate) and arabinofuranase Abf62A (20 U/g substrate), which indicated a notable synergistic effect compared to the 34.42 g/L XOSs produced via Xyn11A. The 50.32 g/L of XOSs products comprised xylobiose (31.71 g/L), xylotriose (15.92 g/L), xylotetraose (1.65 g/L) and xylopentaose (1.04 g/L). Notably, the combined content of xylobiose and xylotriose accounted for up to 94.7%. The XOSs purified from the enzyme hydrolysate could effectually scavenge free radicals, and the antioxidant activity was more than 90%. In summary, XOSs were biologically manufactured from wheat straw xylan through the synergistic biocatalysis via xylanase and arabinofuranosidase Abf62A in a green and sustainable way, rending one kind of prebiotic oligosaccharides with substantial positive effects on human and animal health.
基金Supported by grands from theNaturalScience Foundation of China(39925012 and 30170221 ),and the Scienceand Technology Committee of China (G1999054007).
文摘Objective To investigate effect of inhibiting melatonin biosynthesis on activities of protein kinase A (PKA), glycogen synthase kinase-3 (GSK-3) and tau phosphorylation at PS214 and M4 epitopes using haloperidol, a specific inhibitor of 5-hydroxyindole-O-methyltransferase. Methods Brain ventricular and intraperitoneal injections were used for haloperidol administration, Western blots for tau phosphorylation, 32P-labeling for PKA and GSK-3 activity, and high performance liquid chromatograph for detection of serum melatonin levels. Results Haloperidol injection through the lateral ventricle and intraperitoneal reinforcement significantly stimulated PKA activity with a concurrent hyperphosphorylation of tau at M4 (Thr231/Ser235) and PS214 (Ser214) sites. Prior treatment of the rats using melatonin supplement for one week and reinforcement during the haloperidol administration arrested PKA activity and attenuated tau hyperphosphorylation. GSK-3 activity showed no obvious change after haloperidol injection, however, melatonin supplements and reinforcements during haloperidol infusion inactivated basal activity of GSK-3. Conclusion Decreased melatonin may be involved in Alzheimer-like tau hyperphosphorylation, and overactivation of PKA may play a crucial role in this process.
文摘Selenocysteine (Sec) tRNAs serve as carrier molecules for the biosynthesis of Sec from serine and to donate Sec to protein in response to specific UGA codons. In this study, we describe the current status of Sec tRNAs in higher animals and further we exarnine: (i) the Sec tRNA population in Drosophila; (ii) transcription of the Sec tRNA in vivo (in Xenopus oocytes) and in vitro (in Xenopus oocyte extracts); (iii) the effect of selenium on the Sec tRNA population in various rat tissues following replenishment of extremely selenium deficient rats with this element; and (iv) the biosynthesis of the modified bases on Sec tRNA in Xenopus oocytes
基金financially supported by the Green Development and Demonstration Programme(GUDP)(case number 34009-19-1585)。
文摘Background Post-weaning diarrhea(PWD)in piglets,often caused by F4^(+)enterotoxigenic Escherichia coli(ETEC),poses significant challenges in pig production.Traditional solutions like antibiotics and zinc oxide face increasing restrictions due to growing concerns over antibiotic resistance and environmental sustainability.This study investigates the application of bivalent heavy chain variable domain(V_(H)H)constructs(BL1.2 and BL2.2)targeting ETEC virulence factors,administered in feed to mitigate ETEC-induced PWD in weaned piglets.Results The supplementation of BL1.2 and BL2.2 in both mash and pelleted feed significantly reduced the diarrhea incidence and fecal shedding of F4^(+)ETEC in challenged piglets.Pelleted feed containing V_(H)H constructs helped to preserve gut barrier integrity by maintaining levels of the tight junction protein occludin in the small intestine.Additionally,the constructs maintained blood granulocyte counts at a similar level to the non-challenged control group,including neutrophils,and ameliorated the acute phase protein response after challenge.Notably,even at low feed intake immediately after weaning,V_(H)H constructs helped maintain piglet health by mitigating ETEC-induced inflammation and the resulting diarrhea.Conclusions Our findings demonstrated that using V_(H)H constructs as feed additives could serve as an effective strategy to help manage ETEC-associated PWD,by reducing F4^(+)ETEC gut colonization and supporting gut barrier function of weaned piglets.The high stability of these V_(H)H constructs supports their incorporation into industrial feed manufacturing processes,offering a more sustainable preventive strategy compared to traditional antimicrobial interventions,which could contribute to sustainable farming practices.
文摘The present study was carried out to evaluate the pollution and its effect on the quality of catfish. Four sites in Eygpt were chosen for the research, Ras El-Bar (Site 1) as control, Shatta (Site 2), Kafr El-Bateekh (Site 3), and Talkha (Site 4). The research was carried out on water, sediments and catfish (serum and muscles). Nitrite, nitrate and ammonia were determined in water and sediment. Also, RNA and DNA were determined in serum samples and the muscles of the catfish. In addition, the concentrations of heavy metals (Pb, Cd, Fe, Zn and Cu) were estimated in water, sediments and the muscles of catfish. Also, hepatosomatic index, liver water content, condition factor, lipid and protein contents were determined in the fish. The concentrations of nitrite, nitrate and ammonia in water and sediment of Site 4 and the levels of heavy metals especially Pb and Cd in water, sediment and muscle of catfish from Sites 3 and 4 were highly elevated compared to those of the control. On the other hand, DNA, RNA and protein contents in the catfish of Sites 3 and 4 decreased. The results illustrated that, Cd and Pb levels in the muscle of catfish were negatively correlated with DNA, RNA and with the protein contents. In conclusion, the accumulation of heavy metals in catfish tissues therefore, can cause health problems in human after catfish intake.
基金financially supported by the National Natural Science Foundation of China(31960090,32160562)the Natural Science Foundation of Jiangxi Province(20224BAB215046)the Project Program of State Key Laboratory of Food Science and Resources,Nanchang University(SKLF-ZZB-202129,SKLF-ZZB-202324,SKLF-KF-202216)。
文摘Cyclocarya paliurus(Batalin)Iljinskaja,as a unique and rare monocotyledonous plant in Southern China,is a promising and economical Chinese herbal medicine and functional food.People have conducted a number of research on C.paliurus because of its rich triterpenoids.However,no comprehensive review has illustrated the composition and pharmacological activity of triterpenoids from C.paliurus.This review summarizes 177 triterpenoids from different parts of C.paliurus.The structures of compounds were elucidated,and their biosynthesis was inferred.The biological activities of compounds and triterpenoid-rich extracts,including anti-diabetes,antihyperlipidemia,anti-inflammatory,anticancer or cytotoxicity,antioxidation,etc.,were discussed.C.paliurus can be an important and valuable supplement to the food market.This review provides a reference for the further research and application of C.paliurus triterpenoids in the fields of foods and pharmaceuticals.
基金co-financed by the International Science&Technology Cooperation Program of Hainan Province(GHYF2023009)Jiangsu Provincial Key Research and Development Program(BE2022325)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_0777)Qing Lan Project of Jiangsu Province and Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The surface macromolecules of probiotic bacteria play crucial roles in modulating immune responses in the host.Exopolysaccharide(EPS)from lactic acid bacteria(LAB)have been widely reported to exhibit immunomodulatory activity.In this study,the EPS biosynthesis gene cluster of Lacticaseibacillus paracasei S-NB was analyzed and a deletion mutant S-NBΔ7576(two genes S-NB_2175/wze and S-NB_2176/wzd were responsible for the chain length determination and export of EPS)was successfully constructed,resulting a 40.02%decrease in the production of EPS.The deletion of wze and wzd had little effect on the monosaccharide composition and major groups of the two EPS fractions(BEPS1 and BEPS2).Both BEPS1 and BEPS2 could inhibit the transcriptional level of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),inducible nitric oxide synthase(i NOS)and cyclooxygenase-2(COX-2)mRNA in RAW 264.7 cells induced by lipopolysaccharide(LPS),and enhance host immune tolerance via suppressing NF-κB and MAPK signaling.Notably,the S-NBΔ7576 mutant supplied with the BEPS1/BEPS2 exhibited more significant inhibition of cytokines production and the phosphorylation of p65 and c-Jun N-terminal kinase(JNK)in LPS-stimulated cells compared with the S-NBΔ7576 mutant alone.Our study provided the immunomodulatory effect of BEPS1 and BEPS2 from L.paracasei S-NB,in which the wze and wzd genes associated with EPS biosynthesis may play an important role.
基金supported by the Grand Science and Technology Special Project in Shanxi Province(202201140601025-2)the National Natural Science Foundation of China(32201749)supported by the Agriculture and Food Research Initiative Competitive Grant 2022-68013-36439(WheatCAP)from the USDA National Institute of Food and Agriculture.
文摘The awn can contribute to photosynthesis and carbohydrates,enhancing grain yield in wheat.We mapped QAwn.sxau-5A,a major QTL for awn development in wheat(Triticum aestivum).This QTL was delimited to a 994-kb interval at the B1 locus on chromosome 5A,which included the candidate gene encoding a zinc finger protein(TraesCS5A01G542800)as an awn length inhibitor(ALI).The Ali-A1 allele for the awnless trait showed abundant sequence differences in the promoter regions compared to the ali-A1 allele for the long-awn trait.The results of the swap experiment on the promoters from the two ALI-A1 alleles showed that the two promoters caused a difference in the protein level,indicating the gene was regulated at the transcript level.However,the ali-A1 allele contained an SNP that caused a premature stop codon in its coding region,resulting in a truncated protein compared to the functional Ali-A1 protein.The Ali-A1 protein contained two ethylene-responsive element binding factor-associated amphiphilic repression(EAR)motifs,one at the N terminus(EAR-N)and the other at the C terminus(EAR-C),and they were involved in interactions with the wheat co-repressor protein TOPLESS(TPL1).The ali-A1 protein retained the EAR-N motif but lost the EAR-C motif,resulting in the attenuated ability to interact with TPL1.The tpl1 mutant produced a longer awn compared to the wild type.Ali-A1 repressed the transcription of two downstream genes,TaLRP-A1 and TaARF-B1,involved in endogenous auxin concentrations and auxin responses in wheat.We concluded that the awn length is regulated not only by the ALI-A1 gene at transcript levels but also by Ali-A1 and TPL1 at the protein level in wheat.
基金supported by the National Natural Science Foundation of China(32225009,32370452,82274046)Jilin Agricultural University High-level Talent Introduction Fund(202020218)。
文摘Mammalian scent glands mediate species-specific chemical communication,yet the mechanistic basis for convergent musk production remain incompletely understood.Forest musk deer and muskrat have independently evolved specialized musk-secreting glands,representing a striking case of convergent evolution.Through an integrated multi-omics approach,this study identified cyclopentadecanone as a shared key metabolic precursor in musk from both forest musk deer and muskrat,although downstream metabolite profiles diverged between the two lineages.Single-cell RNA sequencing revealed that these specialized apocrine glands possessed unique secretory architecture and exhibited transcriptional profiles associated with periodic musk production,distinct from those in conventional apocrine glands.Convergent features were evident at the cellular level,where acinar,ductal,and basal epithelial subtypes showed parallel molecular signatures across both taxa.Notably,acinar cells in both species expressed common genes involved in fatty acid and glycerolipid metabolism(e.g.,ACSBG1,HSD17B12,HACD2,and HADHA),suggesting a conserved molecular framework for musk precursor biosynthesis.Metagenomic analysis of musk samples further revealed parallel microbial community structures dominated by Corynebacterium and enriched in lipid metabolic pathways.These findings suggest multi-level convergence in musk biosynthesis,from molecular pathways to microbial communities,providing novel insights into mammalian chemical signaling and artificial musk production.
基金supported by the National Key Research and Development Program of China(2017YFC1600802)Henan Provincial Science and Technology Research Project,China(No.232102110134)the National and Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology of Characteristic Fruit Trees in South Xinjiang of China(No.FE202303).
文摘In plants, transcription factor (TF) family LATERAL ORGAN BOUNDARIES DOMAIN (LBD) has been identified to be involved in the ripening and senescence processes of fruits. However, the function of LBD in Hylocereus undatus (Haw.) Britton & Rose (H. undatus) has not been reported yet. Through transcriptomic analysis, virus-induced gene silencing (VIGS) technology, and RT-qPCR validation, we investigated the role of the LBD TFs in the senescence of H. undatus. Transcriptomic analysis revealed that HuLBD1 is a key transcription factor of the LBD family regulating H. undatus senescence. After silencing HuLBD1, 5075 differentially expressed genes (DEGs) were identified. GSEA results showed that these DEGs were mainly enriched in the phenylpropanoids and flavonoid biosynthesis pathway. The leading subset of genes in these two pathways included 16 DEGs, with four upregulated genes, HuCHS1-2, HuFLS1, HuCYP75B2, and HuCHS5-2 being central in the Protein-Protein Interaction (PPI) network. H. undatus phenotypic experiments confirmed that silencing HuLBD1 significantly increased the flavonoid content in the fruit peel, and RT-qPCR validation showed that the gene expression trends were consistent with the RNA-seq data. The study indicated that HuLBD1 likely delays the fruit senescence process by negatively regulating the expression of four key genes, including HuCHS1-2, thus promoting the synthesis of phenylpropanoids such as flavonoids. In conclusion, our findings suggest that the HuLBD1 TF plays an important role in the senescence of H. undatus fruit, providing a theoretical basis for postharvest senescence control.
文摘Starch is an essential commodity for humans and other animals.Future demands require qualitative and quantitative improvement by crop and post-harvest engineering that calls for comprehensive actions requiring increased fundamental knowledge on starch biosynthesis,development of advanced breeding strategies,efficient farming,and well-adapted and up scalable extraction protocols for diverse starch products.Recent staggering progress in molecular breeding techniques,especially genome editing,have enabled generation of higher starch yield and special functional qualities required to support such advancement.However,this necessitates fundamental biochemical and mechanistic understanding of starch biosynthesis and the variegated starch crop germplasms,all of which are closely linked to the relationships between starch molecular structures and functionality of various starch types as directed by the different capabilities of starch crop genotypes.We here review starch biosynthesis and its genetic foundation with a focus on increasing nutritional and health-promoting value of starch especially through bioengineering of the high amylose trait.
基金supported by the National Natural Science Foundation of China(No.22376111)Shandong Provincial Natural Science Foundation(No.ZR2024YQ026)+2 种基金for Excellent Young Scholars,Taishan Scholar Foundation of Shandong Province(No.tsqn202408237)Youth Innovation Team Project for Talent Introduction and Cultivation in Universities of Shandong Province(No.096-1622002)the Research Foundation for Distinguished Scholars of Qingdao Agricultural University(No.663-1117015)。
文摘In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and environmental risks.In this study,a novel biosynthesis strategy was developed to fabricate fluorescent cellulose by adding fluorescent glucose derivatives to a bacterial fermentation broth.The metabolic activity of bacteria is utilized to achieve in situ polymerization of glucose and its derivatives during the synthesis of bacterial cellulose.Owing to the structural similarity between triphenylamine-modified glucose(TPA-Glc N)and glucose monomers,the TPA-Glc N were efficiently assimilated by the bacterial cells and incorporated into the cellulose matrix,resulting in a uniform distribution of fluorescence.The fluorescence color and intensity of the obtained cellulose could be adjusted by varying the amount of the fluorescent glucose derivatives.Compared to the fluorescent cellulose synthesized through physical dyeing,the fluorescence of the products obtained by in situ polymerization showed higher intensity and stability.Furthermore,fluorescent bacterial cellulose can be hydrolyzed into nanocellulose-based ink,which demonstrates exceptional anti-counterfeiting capabilities under UV light.This biosynthesis method not only overcomes the limitations of traditional modification techniques but also highlights the potential of microbial systems as platforms for synthesizing functional polymers.
基金the National Natural Science Foundation of China(No.22471224)。
文摘A category of highly fused diterpenoid natural products possessing a characteristic perhydropyrene-like or rearranged tetracyclic skeleton structure are distributed in different life forms.Compared to traditional polycyclic diterpenoids,their biosynthetic pathways are quite unique and diverse.Chemists have pinpointed a range of this type of unusual diterpenoids:cycloamphilectanes and isocycloamphilectanes,kempenes and rippertanes,hydropyrene and hydropyrenol,along with recently disclosed cephalotanes.This review describes developments in this field and discusses the challenges associated with synthesizing this class of highly complex compounds.
基金supported by the National Natural Science Foundation of China(32360058)the Central Government Guides Local Science and Technology Development Projects,China(2023ZYZX1224)Xinjiang University Excellent Doctoral Student Innovation Project(XJU2022BS051)。
文摘The black wolfberry(Lycium ruthenicum;2n=2x=24)is an important medicinal plant with ecological and economic value.Its fruits have numerous beneficial pharmacological activities,especially those of anthocyanins,polysaccharides,and alkaloids,and have high nutritional value.However,the lack of available genomic resources for this species has hindered research on its medicinal and evolutionary mechanisms.In this study,we developed the telomere-to-telomere(T2T)nearly gapless genome of L.ruthenicum(2.26 Gb)by integrating PacBio HiFi,Nanopore Ultra-Long,and Hi-C technologies.The assembled genome comprised 12 chromosomes with 37,149 protein-coding genes functionally annotated.Approximately 80%of the repetitive sequences were identified,of which long terminal repeats(LTRs)were the most abundant,accounting for 73.01%.The abundance of LTRs might be the main reason for the larger genome of this species compared to that of other Lycium species.The species-specific genes of L.ruthenicum were related to defense mechanisms,salt tolerance,drought resistance,and oxidative stress,further demonstrating their superior adaptability to arid environments.Based on the assembled genome and fruit transcriptome data,we further constructed an anthocyanin biosynthesis pathway and identified 19 candidate structural genes and seven transcription factors that regulate anthocyanin biosynthesis in the fruit developmental stage of L.ruthenicum,most of which were highly expressed at a later stage in fruit development.Furthermore,154 potential disease resistance-related nucleotidebinding genes have been identified in the L.ruthenicum genome.The whole-genome and proximal,dispersed,and tandem duplication genes in the L.ruthenicum genome enriched the number of genes involved in anthocyanin synthesis and resistance-related pathways.These results provide an important genetic basis for understanding genome evolution and biosynthesis of pharmacologically active components in the Lycium genus.
