The 14th Meeting of the Conference of the Contracting Parties to the Ramsar Convention on Wetlands(COP14)kicked off on November 5 in China’s Wuhan and Switzerland’s Geneva.It is the first time the conference is held...The 14th Meeting of the Conference of the Contracting Parties to the Ramsar Convention on Wetlands(COP14)kicked off on November 5 in China’s Wuhan and Switzerland’s Geneva.It is the first time the conference is held in China,as the world’s most populous nation highlights the harmony between humanity and nature while pushing for modernization.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
Arsbidopsis COP1 （Constitutive Photomorphogenic 1） defines a key repressor of photomorphogenesis in darkness by acting as an E3 ubiquitin Iigase in the nucleus, and is responsible for the targeted degradation of a n...Arsbidopsis COP1 （Constitutive Photomorphogenic 1） defines a key repressor of photomorphogenesis in darkness by acting as an E3 ubiquitin Iigase in the nucleus, and is responsible for the targeted degradation of a number of photomorphogenesis-promoting factors, including phyA, HY5, LAF1, and HFR1. Light activation of multiple classes of photoreceptors （including both phytochromes and cryptochromes） inactivates COP1 and reduces its nuclear abundance, allowing the accumulation of these positively acting light signaling intermediates to promote photomorphogenic development. Recent studies suggest that Arabidopsis COP1 teams up with a family of SPA proteins （SPA1-SPA4） to form the physiologically active COP1-SPA E3 ubiquitin ligase complexes. These COP1-SPA complexes play overlapping and distinct functions in regulating seedling photomorphogenesis under different light conditions and adult plant growth. Further, the COP1-SPA complexes act In concert at a biochemical level with the CDD （COP10, DET1, and DDB1） complex and COP9 signalosome （CSN） to orchestrate the repression of photomorphogenesis.展开更多
Green plants on the earth have evolved intricate mechanisms to acclimatize to and utilize sunlight.In Arabidopsis,light signals are perceived by photoreceptors and transmitted through divergent but overlapping signali...Green plants on the earth have evolved intricate mechanisms to acclimatize to and utilize sunlight.In Arabidopsis,light signals are perceived by photoreceptors and transmitted through divergent but overlapping signaling networks to modulate plant photomorphogenic development.COP1(CONSTITUTIVE PHOTOMORPHOGENIC 1)was first cloned as a central repressor of photomorphogenesis in higher plants and has been extensively studied for over 30 years.It acts as a RING E3 ubiquitin ligase downstream of multiple photoreceptors to target key light-signaling regulators for degradation,primarily as part of large protein complexes.The mammalian counterpart of COP1 is a pluripotent regulator of tumorigenesis and metabolism.A great deal of information on COP1 has been derived from whole-genome sequencing and functional studies in lower green plants,which enables us to illustrate its evolutionary history.Here,we reviewthe current understanding about COP1,with a focus on the conservation and functional diversification of COP1 and its signaling partners in different taxonomic clades.展开更多
文摘The 14th Meeting of the Conference of the Contracting Parties to the Ramsar Convention on Wetlands(COP14)kicked off on November 5 in China’s Wuhan and Switzerland’s Geneva.It is the first time the conference is held in China,as the world’s most populous nation highlights the harmony between humanity and nature while pushing for modernization.
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Supported by Boyce Thompson Institute, Triad Foundation and National Science Foundation （MCB-0420932）. Publication of this paper is supported by the National Natural Science Foundation of China （30624808） and Science Publication Foundation of the Chinese Academy of Sciences.Acknowledgements We thank Dr Xing-Wang Deng（Yale University） and Dr Ute Hoecker（University of Düsseldorf,Germany） for helpful discussion.We also thank Blackwell Publishing and Dr Ute Hoecker for allowing us to use the modified figures （Figures 2,4） in this review.
文摘Arsbidopsis COP1 （Constitutive Photomorphogenic 1） defines a key repressor of photomorphogenesis in darkness by acting as an E3 ubiquitin Iigase in the nucleus, and is responsible for the targeted degradation of a number of photomorphogenesis-promoting factors, including phyA, HY5, LAF1, and HFR1. Light activation of multiple classes of photoreceptors （including both phytochromes and cryptochromes） inactivates COP1 and reduces its nuclear abundance, allowing the accumulation of these positively acting light signaling intermediates to promote photomorphogenic development. Recent studies suggest that Arabidopsis COP1 teams up with a family of SPA proteins （SPA1-SPA4） to form the physiologically active COP1-SPA E3 ubiquitin ligase complexes. These COP1-SPA complexes play overlapping and distinct functions in regulating seedling photomorphogenesis under different light conditions and adult plant growth. Further, the COP1-SPA complexes act In concert at a biochemical level with the CDD （COP10, DET1, and DDB1） complex and COP9 signalosome （CSN） to orchestrate the repression of photomorphogenesis.
基金supported by grants from National Key R&D Program of China(2017YFA0503800)National Natural Science Foundation of China(31330048,31621001)+3 种基金Peking-Tsinghua Center for Life SciencesPeking UniversitySouthern University of Science and TechnologyXiamen University.
文摘Green plants on the earth have evolved intricate mechanisms to acclimatize to and utilize sunlight.In Arabidopsis,light signals are perceived by photoreceptors and transmitted through divergent but overlapping signaling networks to modulate plant photomorphogenic development.COP1(CONSTITUTIVE PHOTOMORPHOGENIC 1)was first cloned as a central repressor of photomorphogenesis in higher plants and has been extensively studied for over 30 years.It acts as a RING E3 ubiquitin ligase downstream of multiple photoreceptors to target key light-signaling regulators for degradation,primarily as part of large protein complexes.The mammalian counterpart of COP1 is a pluripotent regulator of tumorigenesis and metabolism.A great deal of information on COP1 has been derived from whole-genome sequencing and functional studies in lower green plants,which enables us to illustrate its evolutionary history.Here,we reviewthe current understanding about COP1,with a focus on the conservation and functional diversification of COP1 and its signaling partners in different taxonomic clades.
