Flowering is the primary stage of the plant developmental transition and is tightly regulated by environmental factors such as light and temperature.However,the mechanisms by which temperature signals are integrated i...Flowering is the primary stage of the plant developmental transition and is tightly regulated by environmental factors such as light and temperature.However,the mechanisms by which temperature signals are integrated into the photoperiodic flowering pathway are still poorly understood.Here,we demonstrate that HOS15,which is known as a GI transcriptional repressor in the photoperiodic flowering pathway,controls flowering time in response to low ambient temperature.At 16℃,the hos15 mutant exhibits an early flowering phenotype,and HOS15 acts upstream of photoperiodic flowering genes(GI,CO,and FT).GI protein abundance is increased in the hos15 mutant and is insensitive to the proteasome inhibitor MG132.Furthermore,the hos15 mutant has a defect in low ambient temperature-mediated GI degradation,and HOS15 interacts with COP1,an E3 ubiquitin ligase for GI degradation.Phenotypic analyses of the hos15 cop1 double mutant revealed that repression of flowering by HOS15 is dependent on COP1 at 16℃.However,the HOS15-COP1 interaction was attenuated at 16℃,and GI protein abundance was additively increased in the hos15 cop1 double mutant,indicating that HOS15 acts independently of COP1 in GI turnover at low ambient temperature.This study proposes that HOS15 controls GI abundance through multiple modes as an E3 ubiquitin ligase and transcriptional repressor to coordinate appropriate flowering time in response to ambient environmental conditions such as temperature and day length.展开更多
The phytohormone abscisic acid(ABA)regulates multiple physiological processes such as embryo morphogenesis,seed maturation and germination,leaf senescence,fruit ripening,and stress adaptation(Gupta et al.,2020).ABA le...The phytohormone abscisic acid(ABA)regulates multiple physiological processes such as embryo morphogenesis,seed maturation and germination,leaf senescence,fruit ripening,and stress adaptation(Gupta et al.,2020).ABA levels quickly rise in response to conditions leading to water deficit,including the developmental processes of seed drying and dormancy,as well as early post-germinative growth(Chen et al.,2020).Several proteins,commonly regarded as the ABA signaling core components,have been identified.展开更多
基金This research was supported by National Research Foundation of Korea(NRF)grants funded by the Korean Government(MSIT-2022R1A5A1031361 and MSIT-2020R1A2C3014814 to W.-Y.K.)the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2021R1I1A1A01059532 to G.A.and NRF-2019R1I1A1A01041422 to H.J.P.)。
文摘Flowering is the primary stage of the plant developmental transition and is tightly regulated by environmental factors such as light and temperature.However,the mechanisms by which temperature signals are integrated into the photoperiodic flowering pathway are still poorly understood.Here,we demonstrate that HOS15,which is known as a GI transcriptional repressor in the photoperiodic flowering pathway,controls flowering time in response to low ambient temperature.At 16℃,the hos15 mutant exhibits an early flowering phenotype,and HOS15 acts upstream of photoperiodic flowering genes(GI,CO,and FT).GI protein abundance is increased in the hos15 mutant and is insensitive to the proteasome inhibitor MG132.Furthermore,the hos15 mutant has a defect in low ambient temperature-mediated GI degradation,and HOS15 interacts with COP1,an E3 ubiquitin ligase for GI degradation.Phenotypic analyses of the hos15 cop1 double mutant revealed that repression of flowering by HOS15 is dependent on COP1 at 16℃.However,the HOS15-COP1 interaction was attenuated at 16℃,and GI protein abundance was additively increased in the hos15 cop1 double mutant,indicating that HOS15 acts independently of COP1 in GI turnover at low ambient temperature.This study proposes that HOS15 controls GI abundance through multiple modes as an E3 ubiquitin ligase and transcriptional repressor to coordinate appropriate flowering time in response to ambient environmental conditions such as temperature and day length.
基金supported by Next Generation Bio-Green21 Program,Rural Development Administration(RDA),Republic of Korea(SSAC,PJ01318201 to D.-J.Y.and PJ01318205 to J.M.P.)the National Research Foundation of Korea(NRF)funded by the Korean Government(2019R1A2C2084096)Global Research Lab(2017K1A1A2013146).
文摘The phytohormone abscisic acid(ABA)regulates multiple physiological processes such as embryo morphogenesis,seed maturation and germination,leaf senescence,fruit ripening,and stress adaptation(Gupta et al.,2020).ABA levels quickly rise in response to conditions leading to water deficit,including the developmental processes of seed drying and dormancy,as well as early post-germinative growth(Chen et al.,2020).Several proteins,commonly regarded as the ABA signaling core components,have been identified.