红掌CONSTANS类基因AaCOL1和AaCOL2的克隆与表达分析

Molecular Cloning and Expression Analysis of CONSTANS-like Genes,Aa COL1 and Aa COL2 of Anthurium andraeanum

在诱导植物开花的光周期途径中,CONSTANS(CO)家族蛋白起着重要的调节作用。本研究利用RACE技术克隆了红掌(Anthurium andraeanum)CO家族的两个基因,命名为Aa COL1和Aa COL2,全长c DNA分别包含了1 263 bp和1 257 bp的ORF,编码产物都具有2个N端B-box和1个C端CCT基序的CO蛋白保守性结构,系统发育显示两个基因均属于CO家族Ⅲ类成员。转录模式分析表明:Aa COL1和Aa COL2基因的组织表达规律相似,m RNA相对水平都是在根和佛焰苞中较高;但在叶片中,Aa COL1主要受短日照调节,光期转入暗期4 h后表达量最高;而Aa COL2主要受长日照诱导,光期转入暗期即16 h时表达最高。不同的光周期响应模式,暗示Aa COL1和Aa COL2可能以各自特定的方式参与成花调控,结果为进一步解析红掌开花的光调控机制奠定基础。

In flowering plants, the CONSTANS（CO） families play essential roles in the photoperiodic pathway controlling floral transition. In this study, two CONSTANS-like （COL） genes （AaCOLI, AaCOL2）, were cloned by rapid-amplification of eDNA ends （RACE） technology, which full-length eDNA were 1 263 bp and 1 257 bp, respectively. Both the predicted proteins contained two B-box-type zinc fingers and a CCT domain, belong to members of Group HI in CO family though phylogenetic analysis based on amino acid sequence alignment. The results derived from qRT-PCR showed the two genes expressed strongly in root and spathe tissues, but exhibit distinct diurnal expression and light response patterns in foliage. A aCOL1 mRNA level was enhanced significantly after 4 h dark in short-day （SD） cycle, while the transcript level of A aCOL2 with peak level after 16 h light under long-day （LD） conditions. These results suggest that A aCOL1 and A aCOL2 may regulate flowering pathway through particular modules, which will facilitate to expand our understanding about the photoperiod pathway to control flowering in Anthurium.