大豆GmCOL4基因的克隆与分析

CONSTANS(CO)是植物光周期开花途径中的关键基因之一。通过RT-PCR和生物信息学的方法,克隆了大豆GmCOL4基因并分析其结构特征,用实时荧光定量PCR(quantitative real-time RT-PCR,qRT-PCR)研究了其转录特点。结果表明,GmCOL4的4个外显子编码一个具有B-box和CCT保守结构域的CO-like蛋白,在序列上与拟南芥(Arabidopsis thaliana)COL9相似性最高,为64.3%。分析其转录特征发现,GmCOL4表达主要受生物节律的影响,受光的调节作用较弱。器官特异性表达分析发现,GmCOL4主要在大豆叶片中表达,表达模式与COL9相似。这为大豆中CO基因家族的功能研究提供了重要的依据。

Cloning and Analysis of GmCOL4 Gene in Glycine max L.

The model plant Arabosopsis thaliana has been identified to have four major flowering pathways. Among them, the photoperiod pathway integrates the light signal including light/dark cycle, light spectrum, light intensity, and light duration, to mediate flower initiation. CONSTANS(CO) is a key gene in photoperiodic flowering pathway and acts between genes of the circadian clock and meristem identity. CO encodes a protein containing two zinc finger regions (B-box I and II) near the amino terminus and a CCT (CO, CO-Like, TOC1) domain near the carboxy terminus. The CO from Arabidopsis thaliana is one member of the family comprised of 17 members, which can be classed into three subgroups based on their characters of functional domains. To elucidate the function of CO in flowering in soybean, cloned one of CO-like gene, named as GmCOL4, from Glycine max L. Kennong 18. Bioinformatics analysis revealed that GmCOL4 encoded a protein embedded two conserved domains, B-box and CCT, and belonged to subgroup III. Phylogenetic analysis based on the critical amino acid sequences indicated that GmCOL4 was much close to COL9 with similarity of 64.3%. The expression profiles of GmCOL4 by quantitative real-time RT-PCR (qRT-PCR) showed a similar pattern to that of COL9. GmCOL4 was largely regulated by biological circadian, while the light appeared weak effect on it. And GmCOL4 expressed mainly in leaves and had its highest amount in anthesis. The results suggested that GmCOL4 is one of the important genes in the regulation of flowering and photoperiodic in soybean. It paves a way to study the function of CO family in soybean and its application in soybean molecular breeding.