Climate deterioration,water shortages,and abiotic stress are the main threats worldwide that seriously affect cotton growth,yield,and fiber quality.Therefore,research on improving cotton yield and tolerance to biotic ...Climate deterioration,water shortages,and abiotic stress are the main threats worldwide that seriously affect cotton growth,yield,and fiber quality.Therefore,research on improving cotton yield and tolerance to biotic and abiotic stresses is of great importance.The NAC proteins are crucial and plant-specific transcription factors(TFs)that are involved in cotton growth,development,and stress responses.The comprehensive utilization of cotton NAC TFs in the improvement of cotton varieties through novel biotechnological methods is feasible.Based on cotton genomic data,genome-wide identification and analyses have revealed potential functions of cotton NAC genes.Here,we comprehensively summarize the recent progress in understanding cotton NAC TFs roles in regulating responses to drought,salt,and Verticillium wilt-related stresses,as well as leaf senescence and the development of fibers,xylem,and glands.The detailed regulatory network of NAC proteins in cotton is also elucidated.Cotton NAC TFs directly bind to the promoters of genes associated with ABA biosynthesis and secondary cell-wall formation,participate in several biological processes by interacting with related proteins,and regulate the expression of downstream genes.Studies have shown that the overexpression of NAC TF genes in cotton and other model plants improve their drought or salt tolerance.This review elucidates the latest findings on the functions and regulation of cotton NAC proteins,broadens our understanding of cotton NAC TFs,and lays a fundamental foundation for further molecular breeding research in cotton.展开更多
Salinity is a major abiotic stress factor that seriously affects plant growth. Many genes are involved in the response to salt stress with various metabolism pathways. A number of plant transcription factor family gen...Salinity is a major abiotic stress factor that seriously affects plant growth. Many genes are involved in the response to salt stress with various metabolism pathways. A number of plant transcription factor family genes have been found to be involved in the salt stress response, and NAM, ATAF and CUC(NAC) transcription factors are thought to act as active regulators during abiotic stress, especially salt stress. In this study, we detected a rice NAC transcription factor coding gene, OsNAC041, and confirmed that it influenced the germination of seeds under salt stress and salt tolerance of plants. OsNAC041 was primarily expressed in the leaves and located in the nucleus. Furthermore, the CRISPR/Cas9 method was used to obtain a targeted osnac041 mutant, of which the plant height was higher than that of the wild-type, showing increased salt sensitivity. Moreover, RNA-seq analysis revealed a number of differentially expressed genes(DEGs) involved in several important signaling pathways in the osnac041 mutant. Subsequently, Kyoto Encyclopedia of Genes and Genomes annotation also revealed differential expression of DEGs associated with mitogen-activated protein kinase signaling, peroxisome, eukaryotictype ABC transporters, photosynthesis and plant hormones, which are involved in stress-related signaling pathways. Overall, our study suggested that OsNAC041 was involved in the salt stress response in rice. These findings not only provide empirical evidence of OsNAC041 function, but also provide new insight into its potential application in rice resistance breeding.展开更多
Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of ...Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of functional genomics research in foxtail millet（S.italic L.）has been quite limited.NAC（NAM,ATAF1/2 and CUC2）-like transcription factors are known to be involved in various biological processes,including abiotic stress responses.In our previous foxtail millet（S.italic L.）RNA seq analysis,we found that the expression of a NAC-like transcription factor,SiNAC110,could be induced by drought stress;additionally,other references have reported that SiNAC110 expression could be induced by abiotic stress.So,we here selected SiNAC110 for further characterization and functional analysis.First,the predicted SiNAC110 protein encoded indicated SiNAC110 has a conserved NAM（no apical meristem）domain between the 11–139 amino acid positions.Phylogenetic analysis then indicated that SiNAC110 belongs to subfamily III of the NAC gene family.Subcellular localization analysis revealed that the SiNAC110-GFP fusion protein was localized to the nucleus in Arabidopsis protoplasts.Gene expression profiling analysis indicated that expression of SiNAC110 was induced by dehydration,high salinity and other abiotic stresses.Gene functional analysis using SiNAC110 overexpressed Arabidopsis plants indicated that,under drought and high salt stress conditions,the seed germination rate,root length,root surface area,fresh weight,and dry weight of the SiNAC110 overexpressed lines were significantly higher than the wild type（WT）,suggesting that the SiNAC110 overexpressed lines had enhanced tolerance to drought and high salt stresses.However,overexpression of SiN AC110 did not affect the sensitivity of SiNAC110 overexpressed lines to abscisic acid（ABA）treatment.Expression analysis of genes involved in proline synthesis,Na＋/K＋transport,drought responses,and aqueous transport proteins were higher in the SiNAC110overexpressed lines than in the WT,whereas expression of ABA-dependent pathway genes did not change.These results indicated that overexpression of SiNAC110 conferred tolerance to drought and high salt stresses,likely through influencing the regulation of proline biosynthesis,ion homeostasis and osmotic balance.Therefore,SiNAC110 appears to function in the ABA-independent abiotic stress response pathway in plants.展开更多
The NAC transcription factor family is plant-specific with various biological functions.However,there are few studies on the NAC gene involving coniferous species.Bioinformatics research and expression analysis of NAC...The NAC transcription factor family is plant-specific with various biological functions.However,there are few studies on the NAC gene involving coniferous species.Bioinformatics research and expression analysis of NAC genes in Larix olgensis can be used to analyse the function of the NAC gene in the future.Screening of excellent genetic materials and molecular breeding have been utilized to cultivate high-quality,stress-resistant larches.According to the transcriptome data for L.olgensis,the genes Uni-gene81490 and Unigene70699 with complete ORFs(open reading frames)were obtained by conserved domain analy-sis and named LoNAC1 and LoNAC2,respectively.The cDNAs of LoNAC1 and LoNAC2 were 1971 bp and 1095 bp in length,encoding 656 and 364 amino acids,respectively.The molecular weights of the proteins encoded by the two genes were predicted to be 72.61 kDa and 41.13 kDa,and subcellular localization analysis indicated that the proteins were concentrated in the nucleus.The results of real-time quantitative PCR analysis showed that at different growth stages and in different tissues of L.olgensis,the relative expression levels of the two NAC genes were highest in the stem,and the expression differences were more obvious in non-lignified tissues.After drought,salt and alkali stress and hormone treatment,expression was induced to different degrees.The expression levels of LoNAC1 and LoNAC2 in semi-lignified L.olgensis were higher than in the other two periods(non-lignified and lignified),and expression levels significantly increased under drought and salt stress.Relative expression levels changed under hormone treatment.It is speculated that these two genes may not only be related to drought and salt stress and secondary growth but may also be induced by hormones such as abscisic acid.Overall,LoNAC1 and LoNAC2 are genetic materials that can be used for molecular breeding of larch.展开更多
The NAC(NAM,ATAF,and CUC)family is considered one of the largest families of plant transcription factor,and its members are involved in fruit ripening.Abscisic acid(ABA)has been demonstrated to modulate the fruit ripe...The NAC(NAM,ATAF,and CUC)family is considered one of the largest families of plant transcription factor,and its members are involved in fruit ripening.Abscisic acid(ABA)has been demonstrated to modulate the fruit ripening process.By applying the virus-induced gene silencing method and next-generation sequencing technology,we conducted a compara-tive analysis of the eff ects of SNAC4(SlNAC48,accession number:NM 001279348.2)and SNAC9(SlNAC19,accession number:XM 004236996.2)on tomato fruit ripening.The results of high-throughput sequencing identified 1262 significant(p<0.05)diff erentially expressed genes(DEGs)in SNAC4-silenced fruit compared to control fruit,while 655 DEGs were identified in SNAC9-silenced fruit.In addition,we selected 26 and 30 significant DEGs(p<0.05 and log 2-fold change>1.0)related to ABA in SNAC4-silenced and SNAC9-silenced tomatoes,respectively,for further analysis.The XET gene and two other genes(E8 and EXP1)were significantly down and upregulated in SNAC4-silenced tomatoes,respectively.However,the PYL9 gene and four other genes(PP2C,CYP707A2,EXPA6,and ACS6)were significantly down and upregulated in SNAC9-silenced tomatoes,respectively.In addition,ten DEGs were selected for use in tests to confirm the accuracy of the transcriptomic results by quantitative real-time polymerase chain reaction(qRT-PCR).Our results highlight the relationship between SNAC4/9 and ABA in the regulation of tomato ripening,which may help provide a theoretical basis for further research on the mechanisms of tomato fruit ripening and senescence.展开更多
Freezing stress can seriously affect plant growth and development,but the mechanisms of these effects and plant responses to freezing stress require further exploration.Here,we identified a NAM,ATAF1/2,and CUC2(NAC)-f...Freezing stress can seriously affect plant growth and development,but the mechanisms of these effects and plant responses to freezing stress require further exploration.Here,we identified a NAM,ATAF1/2,and CUC2(NAC)-family transcription factor(TF),NAC056,that can promote freezing tolerance in Arabidopsis.NAC056 mRNA levels are strongly induced by freezing stress in roots,and the nac056 mutant exhibits compromised freezing tolerance.NAC056 acts positively in response to freezing by directly promoting key C-repeat-binding factor(CBF)pathway genes.Interestingly,we found that CBF1 regulates nitrate assimilation by regulating the nitrate reductase gene NIA1 in plants;therefore,NAC056–CBF1–NIA1 form a regulatory module for the assimilation of nitrate and the growth of roots under freezing stress.In addition,35S::NAC056 transgenic plants show enhanced freezing tolerance,which is partially reversed in the cbfs triple mutant.Thus,NAC056 confers freezing tolerance through the CBF pathway,mediating plant responses to balance growth and freezing stress tolerance.展开更多
NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,neg...NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,negatively modulates rice immunity against blast and bacterial leaf blight diseases and pathogen-associated molecular pattern(PAMP)-triggered immune responses.MNAC3 binds to a CACG cis-element and activates the transcription of immune-negative target genes OsINO80,OsJAZ10,and OsJAZ11.The negative function of MNAC3 in rice immunity depends on its transcription of downstream genes such as OsINO80 and OsJAZ10.MNAC3 interacts with immunity-related OsPP2C41(a protein phosphatase),ONAC066(a NAC TF),and OsDjA6(a DnaJ chaperone).ONAC066 and OsPP2C41 attenuate MNAC3 transcriptional activity,while OsDjA6 promotes it.Phosphorylation of MNAC3 at S163 is critical for its negative functions in rice immunity.OsPP2C41,which plays positive roles in rice blast resistance and chitin-triggered immune responses,dephosphorylates MNAC3,suppressing its transcriptional activity on the target genes OsINO80,OsJAZ10,and OsJAZ11 and promoting the translocation of MNAC3 from nucleus to cytoplasm.These results establish a MNAC3-centered regulatory network in which OsPP2C41 dephosphorylates MNAC3,attenuating its transcriptional activity on downstream immune-negative target genes in rice.Together,these findings deepen our understanding of molecular mechanisms in rice immunity and offer a novel strategy for genetic improvement of rice disease resistance.展开更多
NAC(NAM/ATAF1/2/CUC2)transcription factors are central switches of growth and stress responses in plants.However,unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC or...NAC(NAM/ATAF1/2/CUC2)transcription factors are central switches of growth and stress responses in plants.However,unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC orthologs inapt for pulse engineering.The knowledge of suitable NAC candidates in hardy pulses like cowpea(Vigna unguiculata(L.)Walp.)is still in infancy,hence warrants immediate biotechnological intervention.Here,we showed that overexpression of two native NAC genes(VuNAC1and VuNAC2)promoted germinative,vegetative,and reproductive growth and conferred multiple abiotic stress tolerance in a commercial cowpea variety.The transgenic lines displayed increased leaf area,thicker stem,nodule-rich denser root system,early flowering,higher pod production(~3.2-fold and~2.1-fold),and greater seed weight(10.3%and 6.0%).In contrast,transient suppression of VuNAC1/2 caused severe growth retardation and flower inhibition.The overexpressor lines showed remarkable tolerance to major yielddeclining terminal stresses,such as drought,salinity,heat,and cold,and recovered growth and seed production by boosting photosynthetic activity,water use efficiency,membrane integrity,Na^(+)/K^(+)homeostasis,and antioxidant activity.The comparative transcriptome study indicated consolidated activation of genes involved in chloroplast development,photosynthetic complexes,cell division and expansion,cell wall biogenesis,nutrient uptake and metabolism,stress response,abscisic acid,and auxin signaling.Unlike their orthologs,VuNAC1/2 direct synergistic transcriptional tuning of stress and developmental signaling to avoid unwanted trade-offs.Their overexpression governs the favorable interplay of photosynthesis and reactive oxygen species regulation to improve stress recovery,nutritional sufficiency,biomass,and production.This unconventional balance of strong stress tolerance and agronomic quality is useful for translational crop research and molecular breeding of pulses.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(32101797)Central Public-interest Scientific Institution Basal Research Fund(No.1610162023020)。
文摘Climate deterioration,water shortages,and abiotic stress are the main threats worldwide that seriously affect cotton growth,yield,and fiber quality.Therefore,research on improving cotton yield and tolerance to biotic and abiotic stresses is of great importance.The NAC proteins are crucial and plant-specific transcription factors(TFs)that are involved in cotton growth,development,and stress responses.The comprehensive utilization of cotton NAC TFs in the improvement of cotton varieties through novel biotechnological methods is feasible.Based on cotton genomic data,genome-wide identification and analyses have revealed potential functions of cotton NAC genes.Here,we comprehensively summarize the recent progress in understanding cotton NAC TFs roles in regulating responses to drought,salt,and Verticillium wilt-related stresses,as well as leaf senescence and the development of fibers,xylem,and glands.The detailed regulatory network of NAC proteins in cotton is also elucidated.Cotton NAC TFs directly bind to the promoters of genes associated with ABA biosynthesis and secondary cell-wall formation,participate in several biological processes by interacting with related proteins,and regulate the expression of downstream genes.Studies have shown that the overexpression of NAC TF genes in cotton and other model plants improve their drought or salt tolerance.This review elucidates the latest findings on the functions and regulation of cotton NAC proteins,broadens our understanding of cotton NAC TFs,and lays a fundamental foundation for further molecular breeding research in cotton.
基金supported by the National Science Foundation of China (Grant No. 31771486)the Sichuan Youth Science and Technology Foundation (Grant No. 2017JQ0005)+1 种基金the National Key Research and Development Program of China (Grant No. 2017YFD01005050102)the National Transgenic Major Project (Grant No. SQ2018ZD08019-001-003)
文摘Salinity is a major abiotic stress factor that seriously affects plant growth. Many genes are involved in the response to salt stress with various metabolism pathways. A number of plant transcription factor family genes have been found to be involved in the salt stress response, and NAM, ATAF and CUC(NAC) transcription factors are thought to act as active regulators during abiotic stress, especially salt stress. In this study, we detected a rice NAC transcription factor coding gene, OsNAC041, and confirmed that it influenced the germination of seeds under salt stress and salt tolerance of plants. OsNAC041 was primarily expressed in the leaves and located in the nucleus. Furthermore, the CRISPR/Cas9 method was used to obtain a targeted osnac041 mutant, of which the plant height was higher than that of the wild-type, showing increased salt sensitivity. Moreover, RNA-seq analysis revealed a number of differentially expressed genes(DEGs) involved in several important signaling pathways in the osnac041 mutant. Subsequently, Kyoto Encyclopedia of Genes and Genomes annotation also revealed differential expression of DEGs associated with mitogen-activated protein kinase signaling, peroxisome, eukaryotictype ABC transporters, photosynthesis and plant hormones, which are involved in stress-related signaling pathways. Overall, our study suggested that OsNAC041 was involved in the salt stress response in rice. These findings not only provide empirical evidence of OsNAC041 function, but also provide new insight into its potential application in rice resistance breeding.
基金funded by the National Key Project for Research on Transgenic Biology, China (2016ZX08002-002)the Innovation Project of Chinese Academy of Agricultural Sciences
文摘Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of functional genomics research in foxtail millet（S.italic L.）has been quite limited.NAC（NAM,ATAF1/2 and CUC2）-like transcription factors are known to be involved in various biological processes,including abiotic stress responses.In our previous foxtail millet（S.italic L.）RNA seq analysis,we found that the expression of a NAC-like transcription factor,SiNAC110,could be induced by drought stress;additionally,other references have reported that SiNAC110 expression could be induced by abiotic stress.So,we here selected SiNAC110 for further characterization and functional analysis.First,the predicted SiNAC110 protein encoded indicated SiNAC110 has a conserved NAM（no apical meristem）domain between the 11–139 amino acid positions.Phylogenetic analysis then indicated that SiNAC110 belongs to subfamily III of the NAC gene family.Subcellular localization analysis revealed that the SiNAC110-GFP fusion protein was localized to the nucleus in Arabidopsis protoplasts.Gene expression profiling analysis indicated that expression of SiNAC110 was induced by dehydration,high salinity and other abiotic stresses.Gene functional analysis using SiNAC110 overexpressed Arabidopsis plants indicated that,under drought and high salt stress conditions,the seed germination rate,root length,root surface area,fresh weight,and dry weight of the SiNAC110 overexpressed lines were significantly higher than the wild type（WT）,suggesting that the SiNAC110 overexpressed lines had enhanced tolerance to drought and high salt stresses.However,overexpression of SiN AC110 did not affect the sensitivity of SiNAC110 overexpressed lines to abscisic acid（ABA）treatment.Expression analysis of genes involved in proline synthesis,Na＋/K＋transport,drought responses,and aqueous transport proteins were higher in the SiNAC110overexpressed lines than in the WT,whereas expression of ABA-dependent pathway genes did not change.These results indicated that overexpression of SiNAC110 conferred tolerance to drought and high salt stresses,likely through influencing the regulation of proline biosynthesis,ion homeostasis and osmotic balance.Therefore,SiNAC110 appears to function in the ABA-independent abiotic stress response pathway in plants.
基金This project was supported by the National Science and Technology Major Project(2018ZX08020003-001-001)the National Natural Science Foundation of China(Grant No.31700595)+1 种基金the Fundamental Research Funds for the Central Universities(2572019BA13)Heilongjiang Touyan Innovation Team Program.
文摘The NAC transcription factor family is plant-specific with various biological functions.However,there are few studies on the NAC gene involving coniferous species.Bioinformatics research and expression analysis of NAC genes in Larix olgensis can be used to analyse the function of the NAC gene in the future.Screening of excellent genetic materials and molecular breeding have been utilized to cultivate high-quality,stress-resistant larches.According to the transcriptome data for L.olgensis,the genes Uni-gene81490 and Unigene70699 with complete ORFs(open reading frames)were obtained by conserved domain analy-sis and named LoNAC1 and LoNAC2,respectively.The cDNAs of LoNAC1 and LoNAC2 were 1971 bp and 1095 bp in length,encoding 656 and 364 amino acids,respectively.The molecular weights of the proteins encoded by the two genes were predicted to be 72.61 kDa and 41.13 kDa,and subcellular localization analysis indicated that the proteins were concentrated in the nucleus.The results of real-time quantitative PCR analysis showed that at different growth stages and in different tissues of L.olgensis,the relative expression levels of the two NAC genes were highest in the stem,and the expression differences were more obvious in non-lignified tissues.After drought,salt and alkali stress and hormone treatment,expression was induced to different degrees.The expression levels of LoNAC1 and LoNAC2 in semi-lignified L.olgensis were higher than in the other two periods(non-lignified and lignified),and expression levels significantly increased under drought and salt stress.Relative expression levels changed under hormone treatment.It is speculated that these two genes may not only be related to drought and salt stress and secondary growth but may also be induced by hormones such as abscisic acid.Overall,LoNAC1 and LoNAC2 are genetic materials that can be used for molecular breeding of larch.
基金supported by the National Natural Science Foundation of China(Nos.31671899 and 31871848)。
文摘The NAC(NAM,ATAF,and CUC)family is considered one of the largest families of plant transcription factor,and its members are involved in fruit ripening.Abscisic acid(ABA)has been demonstrated to modulate the fruit ripening process.By applying the virus-induced gene silencing method and next-generation sequencing technology,we conducted a compara-tive analysis of the eff ects of SNAC4(SlNAC48,accession number:NM 001279348.2)and SNAC9(SlNAC19,accession number:XM 004236996.2)on tomato fruit ripening.The results of high-throughput sequencing identified 1262 significant(p<0.05)diff erentially expressed genes(DEGs)in SNAC4-silenced fruit compared to control fruit,while 655 DEGs were identified in SNAC9-silenced fruit.In addition,we selected 26 and 30 significant DEGs(p<0.05 and log 2-fold change>1.0)related to ABA in SNAC4-silenced and SNAC9-silenced tomatoes,respectively,for further analysis.The XET gene and two other genes(E8 and EXP1)were significantly down and upregulated in SNAC4-silenced tomatoes,respectively.However,the PYL9 gene and four other genes(PP2C,CYP707A2,EXPA6,and ACS6)were significantly down and upregulated in SNAC9-silenced tomatoes,respectively.In addition,ten DEGs were selected for use in tests to confirm the accuracy of the transcriptomic results by quantitative real-time polymerase chain reaction(qRT-PCR).Our results highlight the relationship between SNAC4/9 and ABA in the regulation of tomato ripening,which may help provide a theoretical basis for further research on the mechanisms of tomato fruit ripening and senescence.
基金supported by the National Natural Science Foundation of China(grant nos.32371293,32171232,31500236,and 31570859)the Natural Science Foundation of Shanghai(grant no.22ZR1469500).
文摘Freezing stress can seriously affect plant growth and development,but the mechanisms of these effects and plant responses to freezing stress require further exploration.Here,we identified a NAM,ATAF1/2,and CUC2(NAC)-family transcription factor(TF),NAC056,that can promote freezing tolerance in Arabidopsis.NAC056 mRNA levels are strongly induced by freezing stress in roots,and the nac056 mutant exhibits compromised freezing tolerance.NAC056 acts positively in response to freezing by directly promoting key C-repeat-binding factor(CBF)pathway genes.Interestingly,we found that CBF1 regulates nitrate assimilation by regulating the nitrate reductase gene NIA1 in plants;therefore,NAC056–CBF1–NIA1 form a regulatory module for the assimilation of nitrate and the growth of roots under freezing stress.In addition,35S::NAC056 transgenic plants show enhanced freezing tolerance,which is partially reversed in the cbfs triple mutant.Thus,NAC056 confers freezing tolerance through the CBF pathway,mediating plant responses to balance growth and freezing stress tolerance.
基金supported by grants from the National Natural Science Foundation of China(32072403,31871945)the National Key Research and Development Program of China(2016YFD0100600).
文摘NAC transcription factors(TFs)are pivotal in plant immunity against diverse pathogens.Here,we report the functional and regulatory network of MNAC3,a novel NAC TF,in rice immunity.MNAC3,a transcriptional activator,negatively modulates rice immunity against blast and bacterial leaf blight diseases and pathogen-associated molecular pattern(PAMP)-triggered immune responses.MNAC3 binds to a CACG cis-element and activates the transcription of immune-negative target genes OsINO80,OsJAZ10,and OsJAZ11.The negative function of MNAC3 in rice immunity depends on its transcription of downstream genes such as OsINO80 and OsJAZ10.MNAC3 interacts with immunity-related OsPP2C41(a protein phosphatase),ONAC066(a NAC TF),and OsDjA6(a DnaJ chaperone).ONAC066 and OsPP2C41 attenuate MNAC3 transcriptional activity,while OsDjA6 promotes it.Phosphorylation of MNAC3 at S163 is critical for its negative functions in rice immunity.OsPP2C41,which plays positive roles in rice blast resistance and chitin-triggered immune responses,dephosphorylates MNAC3,suppressing its transcriptional activity on the target genes OsINO80,OsJAZ10,and OsJAZ11 and promoting the translocation of MNAC3 from nucleus to cytoplasm.These results establish a MNAC3-centered regulatory network in which OsPP2C41 dephosphorylates MNAC3,attenuating its transcriptional activity on downstream immune-negative target genes in rice.Together,these findings deepen our understanding of molecular mechanisms in rice immunity and offer a novel strategy for genetic improvement of rice disease resistance.
基金supported by a research grant from the Program Support Grant Phase-II from the Department of Biotechnology,Government of India to L.S. (BT/PR13560/COE/34/44/2015)。
文摘NAC(NAM/ATAF1/2/CUC2)transcription factors are central switches of growth and stress responses in plants.However,unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC orthologs inapt for pulse engineering.The knowledge of suitable NAC candidates in hardy pulses like cowpea(Vigna unguiculata(L.)Walp.)is still in infancy,hence warrants immediate biotechnological intervention.Here,we showed that overexpression of two native NAC genes(VuNAC1and VuNAC2)promoted germinative,vegetative,and reproductive growth and conferred multiple abiotic stress tolerance in a commercial cowpea variety.The transgenic lines displayed increased leaf area,thicker stem,nodule-rich denser root system,early flowering,higher pod production(~3.2-fold and~2.1-fold),and greater seed weight(10.3%and 6.0%).In contrast,transient suppression of VuNAC1/2 caused severe growth retardation and flower inhibition.The overexpressor lines showed remarkable tolerance to major yielddeclining terminal stresses,such as drought,salinity,heat,and cold,and recovered growth and seed production by boosting photosynthetic activity,water use efficiency,membrane integrity,Na^(+)/K^(+)homeostasis,and antioxidant activity.The comparative transcriptome study indicated consolidated activation of genes involved in chloroplast development,photosynthetic complexes,cell division and expansion,cell wall biogenesis,nutrient uptake and metabolism,stress response,abscisic acid,and auxin signaling.Unlike their orthologs,VuNAC1/2 direct synergistic transcriptional tuning of stress and developmental signaling to avoid unwanted trade-offs.Their overexpression governs the favorable interplay of photosynthesis and reactive oxygen species regulation to improve stress recovery,nutritional sufficiency,biomass,and production.This unconventional balance of strong stress tolerance and agronomic quality is useful for translational crop research and molecular breeding of pulses.
