title: Transcription repressor HANABA TARANU controls flower development by integrating the actions of multiple hormones, floral organ specification genes, and GATA3 family genes in Arabidopsis.
abstract: Plant inflorescence meristems and floral meristems possess specific boundary domains that result in proper floral organ separation and specification. HANABA TARANU (HAN) encodes a boundary-expressed GATA3-type transcription factor that regulates shoot meristem organization and flower development in Arabidopsis thaliana, but the underlying mechanism remains unclear. Through time-course microarray analyses following transient overexpression of HAN, we found that HAN represses hundreds of genes, especially genes involved in hormone responses and floral organ specification. Transient overexpression of HAN also represses the expression of HAN and three other GATA3 family genes, HANL2 (HAN-LIKE 2), GNC (GATA, NITRATE-INDUCIBLE, CARBON-METABOLISM-INVOLVED), and GNL (GNC-LIKE), forming a negative regulatory feedback loop. Genetic analysis indicates that HAN and the three GATA3 family genes coordinately regulate floral development, and their expression patterns are partially overlapping. HAN can homodimerize and heterodimerize with the three proteins encoded by these genes, and HAN directly binds to its own promoter and the GNC promoter in vivo. These findings, along with the fact that constitutive overexpression of HAN produces an even stronger phenotype than the loss-of-function mutation, support the hypothesis that HAN functions as a key repressor that regulates floral development via regulatory networks involving genes in the GATA3 family, along with genes involved in hormone action and floral organ specification.
authors: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, People's Republic of China. zhxiaolan@cau.edu.cn
authors: Xiaolan
authors: X
authors: Zhang
authors: Yun
authors: Y
authors: Zhou
authors: Lian
authors: L
authors: Ding
authors: Zhigang
authors: Z
authors: Wu
authors: Renyi
authors: R
authors: Liu
authors: Elliot M
authors: EM
authors: Meyerowitz
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation; D035264:Flowers / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D050980:GATA Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D055503:Protein Multimerization; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D020798:Two-Hybrid System Techniques; D015854:Up-Regulation
chemical_list: D029681:Arabidopsis Proteins; D050980:GATA Transcription Factors; C497900:HANABA TARANU protein, Arabidopsis; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D012333:RNA, Messenger; D018749:RNA, Plant