油菜开花时间调控基因SVP的克隆与表达特性分析

Molecular Cloning and Expression Pattern of SVP Gene Influencing Flowering Time in Brassica napusand Brassica juncea

应用同源克隆法和RT-PCR技术分别从异源四倍体油菜湘油15号和四川黄籽花序组织中克隆了Short veg-etative phase(SVP)基因的同源基因,分别命名为BnSVP-1、BnSVP-2、BnSVP-3、BnSVP-4、BnSVP-5和BjSVP-1、BjSVP-2、BjSVP-3,GenBank登录号分别为JQ906717、JQ906718、JQ906719、JQ906720、JQ316471和JQ906715、JQ906716、JQ316472。序列分析结果表明,这些SVP同源基因编码区长726 bp,编码241个氨基酸残基,具有典型的MIKC结构域,是一类MADS-box调控基因。表达结果分析表明,光周期和GA3处理会使SVP基因的表达模式发生改变,而春化处理后的表达模式与对照相似,其表达模式的改变会导致开花时间提早;在开花前,SVP基因在根、茎、叶组织中均有表达,花期,在花器官的雄蕊、雌蕊和萼片中均有表达,在花瓣中无表达;幼角果的角果皮中该基因的表达水平要高于幼嫩种子。

Mutiple homologs of short vegetative phase（SVP） were isolated from inflorescences of allotetraploid rapeseed cultivars Xiangyou No.15（Brassica napus L.） and Sichuan Yellow-seeded（Brassica juncea L.） by using homologous cloning and reverse transcription PCR technology,which was designated BnSVP-1,BnSVP-2,BnSVP-3,BnSVP-4,BnSVP-5 and BjSVP-1,BjSVP-2,BjSVP-3,respectively.All these sequences have been deposited in GenBank with accession number JQ906717,JQ906718,JQ906719,JQ906720,JQ316471 and JQ906715,JQ906716,JQ316472 respectively.Results of sequence analysis showed that each homolog was 726 bp and encoded 241 amino acids with typical M,I,K and C domain of MADS-box gene.The SVP expression pattern of Xiangyou No.15 after been treated with photoperiod,GA3 spraying and vernalization was studied,the results demonstrated that different photoperiods and GA3 spraying could change its expression in the stem or root,but vernalization did not.The expression change would result in early flowering.In rapeseed,SVP expressed in root,stem and leaf tissues in vegetable phase,but after transition to reproductive phase its expression limited only in floral organ such as stamen,pistil and sepal,no expression was detected in petal.SVP also expressed in young siliques,while more in silique hull than in seed.