Flowering time,a key transition point from vegetative to reproductive growth,is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status.For hundreds of years,nitrogen has been w...Flowering time,a key transition point from vegetative to reproductive growth,is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status.For hundreds of years,nitrogen has been well known to modulate flowering time,but the molecular genetic basis on how plants adapt to ever-changing nitrogen availability remains not fully explored.Here we explore how Arabidopsis natural variation in flowering time responds to nitrate fluctuation.Upon nitrate availability change,we detect accession-and photoperiod-specific flowering responses,which also feature a accession-specific dependency on growth traits.The flowering time variation correlates well with the expression of floral integrators,SOC1 and FT,in an accession-specific manner.We find that gene expression variation of key hub genes in the photoperiod-circadian-clock(GI),aging(SPLs)and autonomous(FLC)pathways associates with the expression change of these integrators,hence flowering time variation.Our results thus shed light on the molecular genetic mechanisms on regulation of accession-and photoperiod-specific flowering time variation in response to nitrate availability.展开更多
Histone modifications affect gene expression, but the mechanism and biological consequence of natural variation in histone modifications remain unclear. Here, we generated genome-wide integrated maps of H3K27me3 modif...Histone modifications affect gene expression, but the mechanism and biological consequence of natural variation in histone modifications remain unclear. Here, we generated genome-wide integrated maps of H3K27me3 modification and transcriptome for Col, C24 and their F1 hybrid. A total of 1,828 genomic regions showing variation in H3K27me3 modification between Col and C24 were identified, most of which were associated with genic regions. Natural variation of H3K27me3 modification between parents could result in aUelic bias of H3K27me3 in hybrids. Furthermore, we found that H3K27me3 variation between Col and C24 was negatively correlated with gene expression differences between two accessions, espe- cially with those arising from the cis-effect. Importantly, mutation of CLF, an Arabidopsis methyltransferase for H3K27,altered gene expression patterns between the parents. Together, these data provide insights into natural variation of histone modifications and their association with gene expression differences between Arabidopsis ecotypes.展开更多
Among plant metabolites,phenolamides,which are conjugates of hydroxycinnamic acid derivatives and polyamines,play important roles in plant adaptation to abiotic and biotic stresses.However,the molecular mechanisms und...Among plant metabolites,phenolamides,which are conjugates of hydroxycinnamic acid derivatives and polyamines,play important roles in plant adaptation to abiotic and biotic stresses.However,the molecular mechanisms underlying phenolamide metabolism and regulation as well as the effects of domestication and breeding on phenolamide diversity in tomato remain largely unclear.In this study,we performed a metabolite-based genome-wide association study and identified two biosynthetic gene clusters(BGC7 and BGC11)containing 12 genes involved in phenolamide metabolism,including four biosynthesis genes(two 4CL genes,one C3H gene,and one CPA gene),seven decoration genes(five AT genes and two UGT genes),and one transport protein gene(DTX29).Using gene co-expression network analysis we further discovered that SlMYB13 positively regulates the expression of two gene clusters,thereby promoting phenolamide accumulation.Genetic and physiological analyses showed that BGC7,BGC11 and SlMYB13 enhance drought tolerance by enhancing scavenging of reactive oxygen species and increasing abscisic acid content in tomato.Natural variation analysis suggested that BGC7,BGC11 and SlMYB13 were negatively selected during tomato domestication and improvement,leading to reduced phenolamide content and drought tolerance of cultivated tomato.Collectively,our study discovers a key mechanism of phenolamide biosynthesis and regulation in tomato and reveals that crop domestication and improvement shapes metabolic diversity to affect plant environmental adaptation.展开更多
Gene gain and loss are crucial factors that shape the evolutionary success of diverse organisms.In the past two decades,more attention has been paid to the significance of gene gain through gene duplication or de novo...Gene gain and loss are crucial factors that shape the evolutionary success of diverse organisms.In the past two decades,more attention has been paid to the significance of gene gain through gene duplication or de novo genes.However,gene loss through natural loss-of-function(LoF)mutations,which isprevalent in the genomes of diverse organisms,has been largely ignored.With the development of sequencing techniques,many genomes have been sequenced across diverse species and can be used to study the evolutionary patterns of gene loss.In this review,we summarize recent advances in research on various aspects of LoF mutations,including their identification,evolutionary dynamics in natural populations,and functional effects.In particular,we discuss how LoF mutations can provide insights into the minimum gene set(or the essential gene set)of an organism.Furthermore,we emphasize their potential impact on adaptation.At the genome level,although most LoF mutations are neutral or deleterious,at least some of them are under positive selection and may contribute to biodiversity and adaptation.Overall,we highlight the importance of natural LoF mutations as a robust framework for understanding biological questions in general.展开更多
基金supported by grants from National Natural Science Foundation of China(31570311 to J-Y H and 31800261 to F C)from the CAS Pioneer Hundred Talents Program(292015312D11035 to J-Y H)+2 种基金CAS Key Laboratory for Plant Diversity and Biogeography of East Asia to J-Y Hfrom the Postdoctoral targeted funding from Yunnan Provincethe Yunnan basic and applied research funding to F C。
文摘Flowering time,a key transition point from vegetative to reproductive growth,is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status.For hundreds of years,nitrogen has been well known to modulate flowering time,but the molecular genetic basis on how plants adapt to ever-changing nitrogen availability remains not fully explored.Here we explore how Arabidopsis natural variation in flowering time responds to nitrate fluctuation.Upon nitrate availability change,we detect accession-and photoperiod-specific flowering responses,which also feature a accession-specific dependency on growth traits.The flowering time variation correlates well with the expression of floral integrators,SOC1 and FT,in an accession-specific manner.We find that gene expression variation of key hub genes in the photoperiod-circadian-clock(GI),aging(SPLs)and autonomous(FLC)pathways associates with the expression change of these integrators,hence flowering time variation.Our results thus shed light on the molecular genetic mechanisms on regulation of accession-and photoperiod-specific flowering time variation in response to nitrate availability.
基金supported by grants from the National Basic Research Program of China(973Program:2012CB910900)the National Natural Science Foundation of China(31330048)+1 种基金Peking-Tsinghua Center for Life Sciences(to X.W.D)State Key Laboratory of Protein and Plant Gene Research
文摘Histone modifications affect gene expression, but the mechanism and biological consequence of natural variation in histone modifications remain unclear. Here, we generated genome-wide integrated maps of H3K27me3 modification and transcriptome for Col, C24 and their F1 hybrid. A total of 1,828 genomic regions showing variation in H3K27me3 modification between Col and C24 were identified, most of which were associated with genic regions. Natural variation of H3K27me3 modification between parents could result in aUelic bias of H3K27me3 in hybrids. Furthermore, we found that H3K27me3 variation between Col and C24 was negatively correlated with gene expression differences between two accessions, espe- cially with those arising from the cis-effect. Importantly, mutation of CLF, an Arabidopsis methyltransferase for H3K27,altered gene expression patterns between the parents. Together, these data provide insights into natural variation of histone modifications and their association with gene expression differences between Arabidopsis ecotypes.
基金supported by grants from the National Key Research and Development Program of China(2022YFF1001900)the Hainan Province Science and Technology Special Fund(no.ZDYF2022XDNY144)+4 种基金the Hainan Provincial Academician Innovation Platform Project(no.HD-YSZX-202004)the Young Elite Scientists Sponsorship Program by CAST(no.2019QNRC001)the Hainan University Startup Fund(no.KYQD(ZR)21025)the Collaborative Innovation Center of Nanfan and High-Efficiency Tropical Agriculture,Hainan University(no.XTCX2022NYB06)the Innovation Project of Postgraduates of Hainan Province(no.Qhyb2022-56).
文摘Among plant metabolites,phenolamides,which are conjugates of hydroxycinnamic acid derivatives and polyamines,play important roles in plant adaptation to abiotic and biotic stresses.However,the molecular mechanisms underlying phenolamide metabolism and regulation as well as the effects of domestication and breeding on phenolamide diversity in tomato remain largely unclear.In this study,we performed a metabolite-based genome-wide association study and identified two biosynthetic gene clusters(BGC7 and BGC11)containing 12 genes involved in phenolamide metabolism,including four biosynthesis genes(two 4CL genes,one C3H gene,and one CPA gene),seven decoration genes(five AT genes and two UGT genes),and one transport protein gene(DTX29).Using gene co-expression network analysis we further discovered that SlMYB13 positively regulates the expression of two gene clusters,thereby promoting phenolamide accumulation.Genetic and physiological analyses showed that BGC7,BGC11 and SlMYB13 enhance drought tolerance by enhancing scavenging of reactive oxygen species and increasing abscisic acid content in tomato.Natural variation analysis suggested that BGC7,BGC11 and SlMYB13 were negatively selected during tomato domestication and improvement,leading to reduced phenolamide content and drought tolerance of cultivated tomato.Collectively,our study discovers a key mechanism of phenolamide biosynthesis and regulation in tomato and reveals that crop domestication and improvement shapes metabolic diversity to affect plant environmental adaptation.
基金supported by the National Natural Science Foundation of China(31925004)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27010305)the Innovative Academy of Seed Design,Chinese Academy of Sciences.
文摘Gene gain and loss are crucial factors that shape the evolutionary success of diverse organisms.In the past two decades,more attention has been paid to the significance of gene gain through gene duplication or de novo genes.However,gene loss through natural loss-of-function(LoF)mutations,which isprevalent in the genomes of diverse organisms,has been largely ignored.With the development of sequencing techniques,many genomes have been sequenced across diverse species and can be used to study the evolutionary patterns of gene loss.In this review,we summarize recent advances in research on various aspects of LoF mutations,including their identification,evolutionary dynamics in natural populations,and functional effects.In particular,we discuss how LoF mutations can provide insights into the minimum gene set(or the essential gene set)of an organism.Furthermore,we emphasize their potential impact on adaptation.At the genome level,although most LoF mutations are neutral or deleterious,at least some of them are under positive selection and may contribute to biodiversity and adaptation.Overall,we highlight the importance of natural LoF mutations as a robust framework for understanding biological questions in general.
