Functional analysis of rice FD homolog

Abstract

Heading date 3a (Hd3a) protein in rice and its Arabidopsis ortholog FT are recently considered as the likely florigen, the crucial component of a long-distance flowering signal. Hd3a/FT protein is generated at the leaf phloem tissue in flowering-promoting conditions, moves from leaves to apical meristem and causes flowering. In Arabisopsis, FD, a bZIP transcription factor expressed at shoot apex, interacts with FT to promote the expression of floral meristem identity genes. Here we identified at least six FD homologs from rice genome. The function of OsFD1, the closest homolog of Arabidopsis FD was examined by overexpressing this gene.