The floral morphology of Cymbidium ensifolium,a well-known orchid in China,has increasingly attracted horticultural and commercial attention.However,the molecular mechanisms that regulate flower development defects in...The floral morphology of Cymbidium ensifolium,a well-known orchid in China,has increasingly attracted horticultural and commercial attention.However,the molecular mechanisms that regulate flower development defects in C.ensifolium mutants are poorly understood.In this work,we examined a domesticated variety of C.ensifolium named‘CuiYuMuDan',or leaf-like flower mutant,which lacks typical characteristics of orchid floral organs but continues to produce sepal-to leaf-like structures along the inflorescence.We used comparative transcriptome analysis to identify 6234 genes that are differentially expressed between mutant and wild-type flowers.The majority of these differentially expre ssed genes are involved in membrane-building,anabolism regulation,and plant hormone signal transduction,implying that in the leaf-like mutant these processes play roles in the development of flower defects.In addition,we identified 152 differentially expre ssed transcription factors,including the bHLH,MYB,MIKC,and WRKY gene families.Moreover,we found 20 differentially expressed genes that are commonly involved in flower development,including MADS-box genes,CLAVATA3(CLV3),WUSCHEL(WUS),and PERIANTHIA(PAN).Among them,floral homeotic genes were further investigated by phylogenetic analysis and expression validation,which displayed distinctive spatial expression patterns and significant changes between the wild type and the mutant.This is the first report on the C.ensifolium leaf-like flower mutant transcriptome.Our results shed light on the molecular regulation of orchid flower development,and may improve our understanding of floral patterning regulation and advance molecular breeding of Chinese orchids.展开更多
Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-r...Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-responsive genes were induced by Cd treat- ment, and that their upregulation was suppressed in bhlh104 loss-of-function mutants, but enhanced upon overexpression of bHLH104. Correspondingly, the bhlh104 mutants displayed sensitivity to Cd stress, whereas plants overexpressing bHLH104 exhibited enhanced Cd tolerance. Further analysis suggested that bHLH104 positivelyregulates four heavy metal detoxification-associated genes, IREG2, A4TP3, HA4A3 and NAS4, which play roles in Cd sequestration and tolerance. The bHLH104 overexpres- sion plants accumulated high levels of Cd in the root but low levels of Cd in the shoot, which might contribute to the Cd tolerance in those lines. The present study thus points to bHLH104 as a potentially useful tool for genetic engineering of plants with enhanced Cd tolerance.展开更多
Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length changes.Seed weight is one of the key traits determining the soybean yield;how-ever,the promine...Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length changes.Seed weight is one of the key traits determining the soybean yield;how-ever,the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly understood.In this study,we identify SwW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1,an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit,as the causal gene of the SW19 locus.We showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in soybean.Further analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo,thus modulating seed weight under long days.However,Dt1 does not function in seed development under short days due to its very low expression.Importantly,we discovered a novel natural allelic variant of Dt1(H4 haplotype)that decouples its pleiotropic effects on seed size and growth habit;i.e.,this variant remains functional in seed development but fails to regulate the stem growth habit of soybean.Collectively,our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes,offering an ideal genetic component for improving soybean's yield by manipulating its seed weightandgrowth habit.展开更多
基金grants from National Key R&D Program(2018YFD1000404)the National Natural Science Foundation of China(31672184)+3 种基金the Natural Science Foundation of Guangdong Province(2017A030312004)Guangzhou Science and Technology Project(201707010307,201904020026)Innovation Team of Modern Agricultural Industry Technology System in Guangdong Province(2019KJ121)the Guangdong Academy of Agricultural Sciences Discipline Team Construction Project(201612TD,2017A070702008,201721).
文摘The floral morphology of Cymbidium ensifolium,a well-known orchid in China,has increasingly attracted horticultural and commercial attention.However,the molecular mechanisms that regulate flower development defects in C.ensifolium mutants are poorly understood.In this work,we examined a domesticated variety of C.ensifolium named‘CuiYuMuDan',or leaf-like flower mutant,which lacks typical characteristics of orchid floral organs but continues to produce sepal-to leaf-like structures along the inflorescence.We used comparative transcriptome analysis to identify 6234 genes that are differentially expressed between mutant and wild-type flowers.The majority of these differentially expre ssed genes are involved in membrane-building,anabolism regulation,and plant hormone signal transduction,implying that in the leaf-like mutant these processes play roles in the development of flower defects.In addition,we identified 152 differentially expre ssed transcription factors,including the bHLH,MYB,MIKC,and WRKY gene families.Moreover,we found 20 differentially expressed genes that are commonly involved in flower development,including MADS-box genes,CLAVATA3(CLV3),WUSCHEL(WUS),and PERIANTHIA(PAN).Among them,floral homeotic genes were further investigated by phylogenetic analysis and expression validation,which displayed distinctive spatial expression patterns and significant changes between the wild type and the mutant.This is the first report on the C.ensifolium leaf-like flower mutant transcriptome.Our results shed light on the molecular regulation of orchid flower development,and may improve our understanding of floral patterning regulation and advance molecular breeding of Chinese orchids.
基金supported by the Candidates of the Young and Middle Aged Academic Leaders of Yunnan Province (2015HB095)the Youth Innovation Promotion Association of CAS
文摘Cd is a non-essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We show that Fe deficiency-responsive genes were induced by Cd treat- ment, and that their upregulation was suppressed in bhlh104 loss-of-function mutants, but enhanced upon overexpression of bHLH104. Correspondingly, the bhlh104 mutants displayed sensitivity to Cd stress, whereas plants overexpressing bHLH104 exhibited enhanced Cd tolerance. Further analysis suggested that bHLH104 positivelyregulates four heavy metal detoxification-associated genes, IREG2, A4TP3, HA4A3 and NAS4, which play roles in Cd sequestration and tolerance. The bHLH104 overexpres- sion plants accumulated high levels of Cd in the root but low levels of Cd in the shoot, which might contribute to the Cd tolerance in those lines. The present study thus points to bHLH104 as a potentially useful tool for genetic engineering of plants with enhanced Cd tolerance.
基金supported by the National Natural Science Foundation of China(grant no.32090064 to F.K.)the National Key R&D Program of China(2021YFF1001203 to X.H.)+3 种基金the“Strategic Priority Research Program"of the Chinese Academy of Sciences(grant no.XDA24010105 to X.H.)the National Natural Science Foundation of China(grant nos.32230078 and 31871643 to X.H.)the Major Program of Guangdong Basic and Applied Research(grant no.2019B030302006 to F.K.)the Guangzhou Municipal Science and Technology Project(grant no.202201010641toY.H.).
文摘Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length changes.Seed weight is one of the key traits determining the soybean yield;how-ever,the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly understood.In this study,we identify SwW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1,an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit,as the causal gene of the SW19 locus.We showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in soybean.Further analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo,thus modulating seed weight under long days.However,Dt1 does not function in seed development under short days due to its very low expression.Importantly,we discovered a novel natural allelic variant of Dt1(H4 haplotype)that decouples its pleiotropic effects on seed size and growth habit;i.e.,this variant remains functional in seed development but fails to regulate the stem growth habit of soybean.Collectively,our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes,offering an ideal genetic component for improving soybean's yield by manipulating its seed weightandgrowth habit.
