CYCLING DOF FACTOR 1 represses transcription through the TOPLESS co‐repressor to control photoperiodic flowering in Arabidopsis

• DOI: 10.1111/tpj.13649
• Publication Date: 2017-07-28T08:46:07Z
• Authors: Greg S. Goralogia; Tong‐Kun Liu; Lin Zhao; Paul M. Panipinto; Evan D. Groover; Yashkarn S. Bains; Takato Imaizumi
• Keywords: Repressor Proteins; 0301 basic medicine; 03 medical and health sciences; Arabidopsis Proteins; Gene Expression Regulation, Plant; Photoperiod; Arabidopsis; Flowers; Co-Repressor Proteins

CYCLING DOF FACTOR 1 (CDF1) and its homologs play an important role in the floral transition by repressing expression of activator genes such as CONSTANS (CO) FLOWERING LOCUS T (FT) Arabidopsis. The day-length-specific removal CDF1-dependent repression is a critical mechanism photoperiodic flowering. However, which CDF1 represses CO FT transcription remained elusive. Here we demonstrate that Arabidopsis CDF proteins contain non-EAR motif-like conserved domains required for interaction with TOPLESS (TPL) co-repressor protein. This TPL confers repressive function on CDF1, mutations N-terminal binding domain largely impair ability protein to repress targets. are present specific regions promoters where binds during morning. In addition, increases when elevated, suggesting recruited these time-dependent fashion CDFs. Moreover, reduction activity induced expressing dominant negative version (tpl-1) phloem companion cells results early flowering decreased sensitivity photoperiod manner similar cdf loss-of-function mutant. Our indicate through formation CDF-TPL transcriptional complex, reduces levels morning seasonal