抄録
Flowers consisting primarily of four basic organ types are the most remarkable feature that characterizes the angiosperms. Floral organ patterning in Arabidopsis requires activation of floral homeotic genes by the floral meristem identity gene, LEAFY (LFY). Here we discuss how precise activation of expression of class B and C homeotic genes in floral meristems is regulated by three flowering time genes, SHORT VEGETATIVE PHASE (SVP), SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and AGAMOUS-LIKE 24 (AGL24), through direct control of a LFY co-regulator, SEPALLATA3 (SEP3). Orchestrated repression of SEP3 by SVP, AGL24 and SOC1 is mediated by recruiting two interacting chromatin regulators, TERMINAL FLOWER 2/LIKE HETEROCHROMATIN PROTEIN 1 and SAP18, a member of SIN3 histone deacetylase complex. Our finding of coordinated regulation of SEP3 by flowering time genes reveals a novel genetic pathway that prevents pre-mature differentiation of floral meristems and determines the appropriate timing of floral organ patterning.
