Light is an important environmental signal that influences plant growth and development.Among the photoreceptors,phytochromes can sense red/far-red light to coordinate various biological processes.However,their functi...Light is an important environmental signal that influences plant growth and development.Among the photoreceptors,phytochromes can sense red/far-red light to coordinate various biological processes.However,their functions in strawberry are not yet known.In this study,we identified an EMS mutant,named P8,in woodland strawberry(Fragaria vesca)that showed greatly increased plant height and reduced anthocyanin content.Mapping-by-sequencing revealed that the causal mutation in FvePhyB leads to premature termination of translation.The light treatment assay revealed that FvePhyB is a bona fide red/far-red light photoreceptor,as it specifically inhibits hypocotyl length under red light.Transcriptome analysis showed that the FvePhyB mutation affects the expression levels of genes involved in hormone synthesis and signaling and anthocyanin biosynthesis in petioles and fruits.The srl mutant with a longer internode is caused by a mutation in the DELLA gene FveRGA1(Repressor of GA1)in the gibberellin pathway.We found that the P8 srl double mutant has much longer internodes than srl,suggesting a synergistic role of FvePhyB and FveRGA1 in this process.Taken together,these results demonstrate the important role of FvePhyB in regulating plant architecture and anthocyanin content in woodland strawberry.展开更多
紫花苜蓿的秋眠与光敏色素基因的表达紧密相关。为了建立一种快速、灵敏检测紫花苜蓿PHYA和PHYB基因mRNA表达水平的实时逆转录聚合酶链反应(FQ-PCR)体系,本研究提取紫花苜蓿叶片总RNA,PCR扩增Actin、PHYA和PHYB基因片段,将其克隆入pMD1...紫花苜蓿的秋眠与光敏色素基因的表达紧密相关。为了建立一种快速、灵敏检测紫花苜蓿PHYA和PHYB基因mRNA表达水平的实时逆转录聚合酶链反应(FQ-PCR)体系,本研究提取紫花苜蓿叶片总RNA,PCR扩增Actin、PHYA和PHYB基因片段,将其克隆入pMD18-T载体进行测序。基于SYBR Green I双链嵌合染料建立检测紫花苜蓿PHYA和PHYB基因mRNA表达水平方法,对PCR产物的熔解曲线进行分析评价其特异性,经测序鉴定目的片段已插入pMD18-T载体内,重组质粒的构建非常成功。为验证其准确性,我们检测紫花苜蓿WL-232 PHYA、PHYB mRNA表达量,结果证明:所建立的测定PHYA和PHYB基因mRNA水平的方法准确,适用于紫花苜蓿的各种组织的大量样本检测。展开更多
Arabidopsis phytochromes （phyA-phyE） are photoreceptors dedicated to sensing red/far-red light. Phyto- chromes promote photomorphogenic developments upon light irradiation via a signaling pathway that involves rapid...Arabidopsis phytochromes （phyA-phyE） are photoreceptors dedicated to sensing red/far-red light. Phyto- chromes promote photomorphogenic developments upon light irradiation via a signaling pathway that involves rapid degradation of PIFs （PHYTOCHROME INTERACTING FACTORS） and suppression of COP1 （CONSTITUTIVE PHOTOMORPHOGENIC 1） nuclear accumulation, through physical interactions with PIFs and COP1, respectively. Both phyA and phyB, the two best characterized phytochromes, regulate plant photomorphogenesis predominantly under far-red light and red light, respectively. It has been demonstrated that SPA1 （SUPPRESSOR OF PHYTOCHROME A 1） associates with COP1 to promote COP1 activity and suppress photomorphogenesis. Here, we report that the mechanism underlying phyB- promoted photomorphogenesis in red light involves direct physical and functional interactions between red-light-activated phyB and SPA1. We found that SPA1 acts genetically downstream of PHYB to repress photomorphogenesis in red light. Protein interaction studies in both yeast and Arabidopsis demonstrated that the photoactivated phyB represses the association of SPA1 with COP1, which is mediated, at least in part, through red-light-dependent interaction of phyB with SPA1. Moreover, we show that phyA physically interacts with SPA1 in a Pfr-form-dependent manner, and that SPA1 acts downstream of PHYA to regulate photomorphogenesis in far-red light. This study provides a genetic and biochemical model of how photo- activated phyB represses the activity of COP1-SPA1 complex through direct interaction with SPA1 to promote photomorphogenesis in red light.展开更多
Growth inhibition and cold-acclimation strategies help plants withstand cold stress,which adversely affects growth and survival.PHYTOCHROME B(phyB)regulates plant growth through perceiving both light and ambient tempe...Growth inhibition and cold-acclimation strategies help plants withstand cold stress,which adversely affects growth and survival.PHYTOCHROME B(phyB)regulates plant growth through perceiving both light and ambient temperature signals.However,the mechanism by which phyB mediates the plant response to cold stress remains elusive.Here,we show that the key transcription factors mediating cold acclimation,C-REPEAT BINDING FACTORs(CBFs),interact with PHYTOCHROME-INTERACTING FACTOR 3(PIF3)under cold stress,thus attenuating the mutually assured destruction of PIF3–phyB.Cold-stabilized phyB acts downstream of CBFs to positively regulate freezing tolerance by modulating the expression of stress-responsive and growth-related genes.Consistent with this,phyB mutants exhibited a freezing-sensitive phenotype,whereas phyB-overexpression transgenic plants displayed enhanced freezing tolerance.Further analysis showed that the PIF1,PIF4,and PIF5 proteins,all of which negatively regulate plant freezing tolerance,were destabilized by cold stress in a phytochrome-dependent manner.Collectively,our study reveals that CBFs–PIF3–phyB serves as an important regulatory module for modulating plant response to cold stress.展开更多
phytochrome B(phyB)acts as the red light photoreceptor and negatively regulates the growth-promoting factor PHYTOCHROME INTERACTING 4(PIF4)through a direct physical interaction,which in turn changes the expression of ...phytochrome B(phyB)acts as the red light photoreceptor and negatively regulates the growth-promoting factor PHYTOCHROME INTERACTING 4(PIF4)through a direct physical interaction,which in turn changes the expression of a large number of genes.phyB-PIF4 module regulates a variety of biological and developmental processes in plants.In this study,we demonstrate that B-BOX PROTEIN 11(BBX11)physically interacts with both phyB and PIF4.BBX11 negatively regulates PIF4 accumulation as well as its biochemical activity,consequently leading to the repression of PIF4-controlled genes’expression and promotion of photomorphogenesis in the prolonged red light.This study reveals a regulatory mechanism that mediates red light signal transduction and sheds a light on phyB-PIF4 module in promoting red light-dependent photomorphognenesis.展开更多
基金This work was supported by the National Natural Science Foundation of China(32172539)the Fundamental Research Funds for the Central Universities(2662022YLPY002).
文摘Light is an important environmental signal that influences plant growth and development.Among the photoreceptors,phytochromes can sense red/far-red light to coordinate various biological processes.However,their functions in strawberry are not yet known.In this study,we identified an EMS mutant,named P8,in woodland strawberry(Fragaria vesca)that showed greatly increased plant height and reduced anthocyanin content.Mapping-by-sequencing revealed that the causal mutation in FvePhyB leads to premature termination of translation.The light treatment assay revealed that FvePhyB is a bona fide red/far-red light photoreceptor,as it specifically inhibits hypocotyl length under red light.Transcriptome analysis showed that the FvePhyB mutation affects the expression levels of genes involved in hormone synthesis and signaling and anthocyanin biosynthesis in petioles and fruits.The srl mutant with a longer internode is caused by a mutation in the DELLA gene FveRGA1(Repressor of GA1)in the gibberellin pathway.We found that the P8 srl double mutant has much longer internodes than srl,suggesting a synergistic role of FvePhyB and FveRGA1 in this process.Taken together,these results demonstrate the important role of FvePhyB in regulating plant architecture and anthocyanin content in woodland strawberry.
基金Supported by National Natural Science Foundation of China(31301682)the Agricultural Science Independent Innovation Foundation of Jiangsu Province[CX(14)5009]+1 种基金National Key Special Project for Breeding and Cultivation of GMO Varieties of China(2013ZX08005)the Jiangsu Province Science and Technology Support Program(BE2014389)~~
文摘紫花苜蓿的秋眠与光敏色素基因的表达紧密相关。为了建立一种快速、灵敏检测紫花苜蓿PHYA和PHYB基因mRNA表达水平的实时逆转录聚合酶链反应(FQ-PCR)体系,本研究提取紫花苜蓿叶片总RNA,PCR扩增Actin、PHYA和PHYB基因片段,将其克隆入pMD18-T载体进行测序。基于SYBR Green I双链嵌合染料建立检测紫花苜蓿PHYA和PHYB基因mRNA表达水平方法,对PCR产物的熔解曲线进行分析评价其特异性,经测序鉴定目的片段已插入pMD18-T载体内,重组质粒的构建非常成功。为验证其准确性,我们检测紫花苜蓿WL-232 PHYA、PHYB mRNA表达量,结果证明:所建立的测定PHYA和PHYB基因mRNA水平的方法准确,适用于紫花苜蓿的各种组织的大量样本检测。
文摘Arabidopsis phytochromes （phyA-phyE） are photoreceptors dedicated to sensing red/far-red light. Phyto- chromes promote photomorphogenic developments upon light irradiation via a signaling pathway that involves rapid degradation of PIFs （PHYTOCHROME INTERACTING FACTORS） and suppression of COP1 （CONSTITUTIVE PHOTOMORPHOGENIC 1） nuclear accumulation, through physical interactions with PIFs and COP1, respectively. Both phyA and phyB, the two best characterized phytochromes, regulate plant photomorphogenesis predominantly under far-red light and red light, respectively. It has been demonstrated that SPA1 （SUPPRESSOR OF PHYTOCHROME A 1） associates with COP1 to promote COP1 activity and suppress photomorphogenesis. Here, we report that the mechanism underlying phyB- promoted photomorphogenesis in red light involves direct physical and functional interactions between red-light-activated phyB and SPA1. We found that SPA1 acts genetically downstream of PHYB to repress photomorphogenesis in red light. Protein interaction studies in both yeast and Arabidopsis demonstrated that the photoactivated phyB represses the association of SPA1 with COP1, which is mediated, at least in part, through red-light-dependent interaction of phyB with SPA1. Moreover, we show that phyA physically interacts with SPA1 in a Pfr-form-dependent manner, and that SPA1 acts downstream of PHYA to regulate photomorphogenesis in far-red light. This study provides a genetic and biochemical model of how photo- activated phyB represses the activity of COP1-SPA1 complex through direct interaction with SPA1 to promote photomorphogenesis in red light.
基金This work was supported by grants from the Ministry of Agriculture of China,China(2016ZX08009003-002)the National Natural Science Foundation of China,China(31872658,31921001)Discipline Program of Beijing Outstanding University,China.
文摘Growth inhibition and cold-acclimation strategies help plants withstand cold stress,which adversely affects growth and survival.PHYTOCHROME B(phyB)regulates plant growth through perceiving both light and ambient temperature signals.However,the mechanism by which phyB mediates the plant response to cold stress remains elusive.Here,we show that the key transcription factors mediating cold acclimation,C-REPEAT BINDING FACTORs(CBFs),interact with PHYTOCHROME-INTERACTING FACTOR 3(PIF3)under cold stress,thus attenuating the mutually assured destruction of PIF3–phyB.Cold-stabilized phyB acts downstream of CBFs to positively regulate freezing tolerance by modulating the expression of stress-responsive and growth-related genes.Consistent with this,phyB mutants exhibited a freezing-sensitive phenotype,whereas phyB-overexpression transgenic plants displayed enhanced freezing tolerance.Further analysis showed that the PIF1,PIF4,and PIF5 proteins,all of which negatively regulate plant freezing tolerance,were destabilized by cold stress in a phytochrome-dependent manner.Collectively,our study reveals that CBFs–PIF3–phyB serves as an important regulatory module for modulating plant response to cold stress.
基金by a grant from the National Natural Science Foundation of China(31970258)by start-up funding from Nan-jing Agricultural University(to D.X.)+2 种基金by grants from Jiangsu‘‘In-novative and Entrepreneurial Talent’’program(to D.X.)Nanjing Science and Technology Innovation Program for Overseas Stu-dents(to D.X.)the Jiangsu Collaborative Innovation Center for Modern Crop Production.
文摘phytochrome B(phyB)acts as the red light photoreceptor and negatively regulates the growth-promoting factor PHYTOCHROME INTERACTING 4(PIF4)through a direct physical interaction,which in turn changes the expression of a large number of genes.phyB-PIF4 module regulates a variety of biological and developmental processes in plants.In this study,we demonstrate that B-BOX PROTEIN 11(BBX11)physically interacts with both phyB and PIF4.BBX11 negatively regulates PIF4 accumulation as well as its biochemical activity,consequently leading to the repression of PIF4-controlled genes’expression and promotion of photomorphogenesis in the prolonged red light.This study reveals a regulatory mechanism that mediates red light signal transduction and sheds a light on phyB-PIF4 module in promoting red light-dependent photomorphognenesis.
