北京林业大学学报2017，Vol.39Issue(4)：63-71,9.DOI:10.13332/j.1000-1522.20170003
春黄菊族部分植物CYC2 d同源基因的分离与功能初步分析
Isolation and functional analysis of CYC2d orthologous genes from several plants of the tribe Anthemideae
摘要
Abstract
As the important gene of regulating flower symmetry, cyc-like proteins have been shown to mainly regulate the identity and development of ray floret ( bilaterally symmetrical) in Asteraceae. The presence or absence of ray floret in Asteraceae and its molecular regulation mechanism as well as the evolutionary process have been highly concerned. Orthologous genes of CYC2d from Ajania potaninii, Brachanthemum titovii and Chrysanthemum indicum var. aromaticum were obtained by homology-based cloning. Their sequence alignment and conserved motif analysis were performed with the amino sequence of CmCYC2d, respectively. The results showed that their homology was more than 90% and all these proteins contained the conserved TCP and R domains. Furthermore, according to the result of semi-quantitative RT-PCR assay, CYC2d was strongly expressed in the young inflorescence of the groundcover chrysanthemum'Mao xiangyu', while slightly expressed in that of A. potaninii and B. titovii. Therefore, the transcription levels of CmCYC2 d were examined in ray and disc florets of 'Mao xiangyu ' at six developing stages using quantitative real-time PCR. The results indicated that it was weakly expressed in disc florets of all stages, while highly expressed in ray florets of the corresponding stages. Moreover, in three F1 progenies with various whorls of ray florets, the CmCYC2d was expressed at much higher levels in ray florets of different whorls than in disc florets. The recombinant plasmid pSUPER1300-CmCYC2d-GFP was transiently expressed into the epidermal cells of Nicotiana benthamiana by agrobacterium-mediated transformation, and subcellular localization analysis revealed that the CmCYC2 d protein mainly localized into the nucleus of epidermal cells. Furthermore, CmCYC2d was overexpressed in wild type Arabidopsis and the TCP1 mutant used the floral-dip method. The results showed that the vegetative growth and the flowering time of the positive transgenic lines were repressed and postponed. Moreover, the size and arrangement of the petals seemed to be changed, making the petal arrangement showed bilateral symmetry from original radial symmetry. These results indicate that the transcription factor CmCYC2d is essential in regulating ray floret identity in chrysanthemum. Our study lays a foundation for the research of molecular mechanisms for the evolutionary process of ray floret in Asteraceae.关键词
花对称性/菊属/春黄菊族/CmCYC2d/舌状花/基因表达Key words
flower symmetry/Chrysanthemum/Anthemideae/CmCYC2 d/ray floret/gene expression分类
农业科技引用本文复制引用
黄笛,孙明,袁存权,程堂仁,王佳,张启翔..春黄菊族部分植物CYC2 d同源基因的分离与功能初步分析[J].北京林业大学学报,2017,39(4):63-71,9.基金项目
"十二五"国家科技支撑计划项目(2013BAD01B07)、北京市共建项目(2016). （2013BAD01B07）
