HOS15 represses flowering by promoting GIGANTEA degradation in response to low temperature in Arabidopsis  

作　　者：Gyeongik Ahn Hee Jin Park Song Yi Jeong Gyeong-Im Shin Myung Geun Ji Joon-Yung Cha Jeongsik Kim Min Gab Kim Dae-Jin Yun Woe-Yeon Kim 

机构地区：[1]Research Institute of Life Science,Institute of Agricultural and Life Science,Gyeongsang National University,Jinju 52828,Republic of Korea [2]Division of Applied Life Science(BK21 Four),Plant Biological Rhythm Research Center,Plant Molecular Biology and Biotechnology Research Center,Graduate School of Gyeongsang National University,Jinju 52828,Republic of Korea [3]Department of Biological Sciences,College of Natural Sciences,Chonnam National University,Gwangju 61186,Republic of Korea [4]Faculty of Science Education and Interdisciplinary Graduate Program in Advanced Convergence Technology and Science,Jeju National University,Jeju 63243,Republic of Korea [5]College of Pharmacy and Research Institute of Pharmaceutical Science,PMBBRC,Gyeongsang National University,Jinju 52828,Republic of Korea [6]Institute of Glocal Disease Control,Konkuk University,Seoul 05029,Republic of Korea [7]Key Laboratory of Molecular Epigenetics of the Ministry of Education(MOE),Northeast Normal University,Changchun 130024,China

出　　处：《Plant Communications》2023年第4期225-239,共15页植物通讯（英文）

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.)。

摘　　要：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.

关 键 词：ARABIDOPSIS flowering response low ambient temperature HOS15 GIGANTEA 

分 类 号：Q945[生物学—植物学]