TCP7 functions redundantly with several Class Ⅰ TCPs and regulates endoreplication in Arabidopsis  

作　　者：Guofang Zhang Hongtao Zhao Chunguang Zhang Xiaoyun Li Yuanyuan Lyu Dongmei Qi Yanwei Cui Lin Hu Zhenjie Wang Zheng Liang Sujuan Cui 

机构地区：[1]Hebei Key Laboratory of Molecular and Cellular Biology,Hebei Normal University,Shijiazhuang 050024,China [2]Key Laboratory of Molecular and Cellular Biology of Ministry of Education,Hebei Normal University,Shijiazhuang 050024,China [3]Hebei Collaboration Innovation Center for Cell Signaling,Hebei Normal University,Shijiazhuang 050024,China [4]College of Life Science,Hebei Normal University,Shijiazhuang 050024,China

出　　处：《Journal of Integrative Plant Biology》2019年第11期1151-1170,共20页植物学报（英文版）

基　　金：supported by the Natural Science Foundation of Hebei Province (C2009001516);the Program for New Century Excellent Talents in University (06-0256);the National Natural Science Foundation of China (31171170, 30871421, 31771351 and 31400240);the Hebei Provincial Natural Science Foundation of China (C2015205184);the Hebei Education Department (GCC2014029 and BJ2014040);the Postdoctoral Science Foundation of China (20080430862)

摘　　要：TCP(TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR) proteins, a family of plantspecific transcription factors, play important roles in many developmental processes. However, genetic and functional redundancy among class I TCP limits the analysis of their biological roles. Here, we identified a dominantnegative mutant of Arabidopsis thaliana TCP7 named leaf curling-upward(lcu), which exhibits smaller leaf cells and shorter hypocotyls than the wild type, due to defective endoreplication. A septuple loss-of-function mutant of TCP7, TCP8, TCP14, TCP15, TCP21, TCP22, and TCP23 displayed similar developmental defects to those of lcu.Genome-wide RNA-sequencing showed that lcu and the septuple mutant share many misexpressed genes.Intriguingly, TCP7 directly targets the CYCLIN D1;1 (CYCD1;1) locus and activates its transcription. We determined that the C-terminus of TCP7 accounts for its transcriptional activation activity. Furthermore, the mutant protein LCU exhibited reduced transcriptional activation activity due to the introduction of an EAR-like repressive domain at its C-terminus. Together, these observations indicate that TCP7 plays important roles during leaf and hypocotyl development, redundantly, with at least six class I TCPs, and regulates the expression of CYCD1;1 to affect endoreplication in Arabidopsis.TCP(TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR) proteins, a family of plantspecific transcription factors, play important roles in many developmental processes. However, genetic and functional redundancy among class I TCP limits the analysis of their biological roles. Here, we identified a dominantnegative mutant of Arabidopsis thaliana TCP7 named leaf curling-upward(lcu), which exhibits smaller leaf cells and shorter hypocotyls than the wild type, due to defective endoreplication. A septuple loss-of-function mutant of TCP7, TCP8, TCP14, TCP15, TCP21, TCP22, and TCP23 displayed similar developmental defects to those of lcu.Genome-wide RNA-sequencing showed that lcu and the septuple mutant share many misexpressed genes.Intriguingly, TCP7 directly targets the CYCLIN D1;1 (CYCD1;1) locus and activates its transcription. We determined that the C-terminus of TCP7 accounts for its transcriptional activation activity. Furthermore, the mutant protein LCU exhibited reduced transcriptional activation activity due to the introduction of an EAR-like repressive domain at its C-terminus. Together, these observations indicate that TCP7 plays important roles during leaf and hypocotyl development, redundantly, with at least six class I TCPs, and regulates the expression of CYCD1;1 to affect endoreplication in Arabidopsis.

关 键 词：ARABIDOPSIS ACTIVATION REDUNDANT 

分 类 号：Q94[生物学—植物学]