Molecular basis of CONSTANS oligomerization in FLOWERING LOCUS T activation

作     者：Xiaolin Zeng Xinchen Lv Rui Liu Hang He Shiqi Liang Lixian Chen Fan Zhang Liu Chen Yuehui He Jiamu Du Xiaolin Zeng;Xinchen Lv;Rui Liu;Hang He;Shiqi Liang;Lixian Chen;Fan Zhang;Liu Chen;Yuehui He;Jiamu Du

作者机构：Peking-Tsinghua Center for Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871 China National Key Laboratory of Plant Molecular Genetics&Shanghai Center for Plant Stress BiologyChinese Academy of Sciences Center for Excellence in Molecular Plant SciencesShanghai201602 China Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education InstitutesInstitute of Plant and Food ScienceDepartment of BiologySchool of Life SciencesSouthern University of Science and TechnologyShenzhen518055 China Peking University Institute of Advanced Agricultural SciencesWeifang261000 China 

出 版 物：《Journal of Integrative Plant Biology》 (植物学报（英文版）)

年 卷 期：2022年第64卷第3期

页      面：731-740页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 071007[理学-遗传学] 

基　　金：supported by the Shenzhen Science and Technology Program(JCYJ20200109110403829 and KQTD20190929173906742 to Jiamu Du) the National Natural Science Foundation of China(31721001 to Yuehui He) the National Key Research and Development Program of China(2017YFA0503803 to Yuehui He) the Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes(2019KSYS006 to Jiamu Du)。 

主　　题：B-box domain CONSTANS crystal structure FLOWERING LOCUS T photoperiod 

摘      要：The transcription factor CONSTANS(CO)integrates day-length information to induce the expression of florigen FLOWERING LOCUS T(FT)in Arabidopsis.We recently reported that the C-terminal CCT domain of CO forms a complex with NUCLEAR FACTOR-YB/YC to recognize multiple cis-elements in the FT promoter,and the N-terminal tandem B-box domains form a homomultimeric assembly.However,the mechanism and biological function of CO multimerization remained unclear.Here,we report that CO takes on a head-to-tail oligomeric configuration via its B-boxes to mediate FT activation in long days.The crystal structure of B-boxesCOreveals a closely connected tandem B-box fold forming a continuous head-to-tail assembly through unique CDHH zinc fingers.Mutating the key residues involved in CO oligomerization resulted in a non-functional CO,as evidenced by the inability to rescue co mutants.By contrast,a transgene encoding a human p53-derived tetrameric peptide in place of the B-boxesCOrescued co mutant,emphasizing the essential role of BboxesCO-mediated oligomerization.Furthermore,we found that the four TGTG-bearing cis-elements in FT proximal promoter are required for FT activation in long days.Our results suggest that CO forms a multimer to bind to the four TGTG motifs in the FT promoter to mediate FT activation.