HOP co-chaperones contribute to GA signaling by promoting the accumulation of the F-box protein SNE in Arabidopsis  

作　　者：Silvina Mangano Alfonso Muñoz Lourdes Fernández-Calvino M.Mar Castellano 

机构地区：[1]Centro de Biotecnología y Genómica de Plantas,Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA/CSIC),Campus Montegancedo UPM,28223 Pozuelo de Alarcón(Madrid),Spain [2]Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires(IIBA,CONICET),Av.Patricias Argentinas 435,Buenos Aires C1405BWE,Argentina [3]Departamento de Botánica,Ecologíay Fisiología Vegetal,Campus de Rabanales,Edificio Severo Ochoa,Universidad de Córdoba,14071 Córdoba,Spain

出　　处：《Plant Communications》2023年第3期244-257,共14页植物通讯（英文）

基　　金：supported by the project RTI2018-095946-B-I00 and PID2021-126956OB-I00 from MICIU;by"Severo Ochoa Programme for Centres of Excellence in R&D"from the Agencia Estatal de Investigación of Spain(grants SEV-2016-0672 and CEX2020-000999-S to the CBGP);In the frame of this latter program,S.M.was supported with postdoctoral contracts.We also acknowledge the grant"Recualificación del profesorado universitario"from the Ministerio de Universidades to A.M.(UCO).

摘　　要：Gibberellins(GAs)play important roles in multiple developmental processes and in plant response to the environment.Within the GA pathway,a central regulatory step relies on GA-dependent degradation of the DELLA transcriptional regulators.Nevertheless,the relevance of the stability of other key proteins in this pathway,such as SLY1 and SNE(the F-box proteins involved in DELLA degradation),remains unknown.Here,we take advantage of mutants in the HSP70-HSP90 organizing protein(HOP)co-chaperones and reveal that these proteins contribute to the accumulation of SNE in Arabidopsis.Indeed,HOP proteins,along with HSP90 and HSP70,interact in vivo with SNE,and SNE accumulation is significantly reduced in the hop mutants.Concomitantly,greater accumulation of the DELLA protein RGA is observed in these plants.In agreement with these molecular phenotypes,hop mutants show a hypersensitive response to the GA inhibitor paclobutrazol and display a partial response to the ectopic addition of GA when GA-regulated processes are assayed.These mutants also display different phenotypes associated with alterations in the GA pathway,such as reduced germination rate,delayed bolting,and reduced hypocotyl elongation in response to warm temperatures.Remarkably,ectopic overexpression of SNE reverts the delay in germination and the thermally dependent hypocotyl elongation defect of the hop1 hop2 hop3 mutant,revealing that SNE accumulation is the key aspect of the hop mutant phenotypes.Together,these data reveal a pivotal role for HOP in SNE accumulation and GA signaling.

关 键 词：HSP70-HSP90 organizing protein seed germination thermomorphogenesis RGA protein folding protein stability 

分 类 号：Q94[生物学—植物学]