菜薹叶片衰老相关转录因子BrWRKY75的特性分析  

Molecular Characterization of a Transcription Factor BrWRKY75 Related to Leaf Senescence of Chinese Flowering Cabbage

作　　者：谭小丽[1] 范中奇 李露露[1] 吴亚[1] 邝健飞[1] 陆旺金[1] 陈建业[1] 

机构地区：[1]华南农业大学园艺学院,亚热带农业生物资源保护与利用国家重点实验室,南方园艺产品保鲜教育部工程研究中心广东省果蔬保鲜重点实验室,广州510642

出　　处：《园艺学报》2016年第6期1089-1098,共10页Acta Horticulturae Sinica

基　　金：‘十二五’国家科技支撑计划课题(2013BAD19B07)

摘　　要：以菜薹[Brassica rapa L.ssp.chinensis(L.)Mokino var.utilis Tsen et Lee]为材料,克隆得到1个WRKY转录因子,命名为BrWRKY75。氨基酸序列比对及进化树分析发现BrWRKY75与拟南芥的WRKY75同源性较高,且同属于第Ⅱ类c亚族。实时荧光定量PCR表明BrWRKY75在菜薹叶片衰老过程中表达明显增强。亚细胞定位和转录活性分析显示BrWRKY75定位于细胞核,是一种核蛋白,并且具有转录抑制活性。体外凝胶阻滞试验(EMSA)证实Br WRKY75能与W-box(TTGAC)元件特异结合。上述结果为进一步研究菜薹叶片衰老的转录调控机制奠定了基础。In the present work,a WRKY transcription factor,termed BrWRKY75 was isolated from Chinese flowering cabbage. Analysis of deduced amino acid sequence and phylogenetic tree found that BrWRKY75 showed high homology with Brassica oleracea WRKY75 and Arabidopsis thaliana WRKY75,and belong to Ⅱ c sub-group. Real-time quantitative PCR displayed that BrWRKY75 was up-regulated during leaf senescence of Chinese flowering cabbage. Sub-cellular localization and transcriptional activity analysis revealed that BrWRKY75 is a nuclear protein with transcriptional repression activity. In addition,electrophoretic mobility shift assay（EMSA）confirmed that BrWRKY75 directly bound to the W-box（TTGAC）cis-element. Taken together,these results provide basis for the further investigation of the transcriptional regulation mechanism of Chinese flowering cabbage leaf senescence.

关 键 词：菜薹 叶片衰老 WRKY转录因子 转录调控 

分 类 号：S634.5[农业科学—蔬菜学]