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抽薹开花是白菜类作物很重要的农艺性状.开花抑制基因FLOWERING LOCUS C (FLC)是春化过程中的关键基因,并受多个途径的调控.本研究从乌菜(Brassica campestris L.ssp.Chinensis var.Rosularis)中克隆得到FLC序列,命名为BcFLC2,开放阅读框长度591 bp,编码196个氨基酸.序列分析表明,该基因属于Ⅱ型MADS-box家族基因,其蛋白序列二级结构主要由α-螺旋、β-转角及无规则卷曲构成,属于亲水蛋白,亚细胞定位于线粒体中.序列比对及进化树分析发现,该蛋白序列与紫菜苔(B.rapa var.purpuraria)、菜心(B.rapa subsp.chinensis)FLC序列具有较高的同源性(98％).荧光定量PCR分析表明,随着乌菜的发育,BcFLC2基因在叶片中的表达量逐渐降低;在不同组织中表达差异显著,其中,叶中表达量最高,茎和蕾次之,根中不表达.以上结果表明,BcFLC2基因在乌菜抽薹开花中起到重要的作用.“,”Bolting and flowering are the very important agronomic traits in Brassica campestris crops.FLOWER-ING LOCUS C (FLC), regulating the flowering, is a key gene in the vernalization, which is controlled by several pathways.In this study, one FLOWERING LOCUS C homologous gene BcFLC2, was cloned from Wucai (Brassica campestris L.ssp.Chinensis var.Rosularis) which had a 591 bp open reading frame (ORF) and encoded 196 amino acids.Sequence analysis showed that the protein belonged to the MADS-box super family of typeⅡ.The secondary structure of BcFLC2 protein sequence, which was a hydrophilic protein, was mainly constructed by alpha helix, beta turn and random coil, and the subcellular was in the mitochondrion.Sequence alignment and phylogenetic analysis found that the protein sequences in Wucai were highly homologous at 98％with the FLC sequence in B.rapa va r.Purpuraria and B.rapa subsp.Chinensis.q RT-PCR analysis showed that the expressing level of BcFLC2 gene in leaves gradually decreased with the development of Wucai and displayed significant expression differences in the different organs of Wucai.Highest expression levels were observed in the leaves, followed by stems and buds and there was no expression in roots.These results indicated that BcFLC2 gene had an important effect on the bolting and flowering in Wucai.