关键词: 茶树, LEAFY, 基因克隆, 表达分析

Abstract: This study cloned two kinds of full-length cDNA of LEAFY（LFY）homologs from a flowerless mutant with large leaves Camellia sinensis‘Dayelong’and the mother plant by using the homology cloning and RACE-PCR techniques，and the two sequences were designated as CsLFL1 and CsLFL2. They comprise 1 448 bp and 1 466 bp，with intact ORFs of 1 191 bp and 1 197 bp，encoding polypeptides of 396 and 398 amino acid residues，respectively. They present 77%–79% similarities with LFY representatives in species from Anacardiaceae，Sapindaceae and Fagales，and contain such typical structural features as proline-rich region，leucine repeat region，acidic and basic domains，and conserved C-terminus characteristic of LFY members as transcription factors. Phylogenetic analysis indicates that they belong to the LFY clade of dicots，and they are the most closely related，implying that they derived from duplication occurring in later stages during the evolution of C. sinensis. Moreover，there are no difference between the sequences from the normally flowering mother plant and the mutant，whereas they are expressed strongly in floral buds of the mother plant，and also weakly in leaf buds of both the mother plants and the mutant. These results suggest that CsLFL1 and CsLFL2 represent the LFY orthologs fromtea and are likely to function in flower initiation in tea plants.

Key words: Camellia sinensis, LEAFY, gene cloning, expression analysis