AhCYCB1基因的克隆和在ABA抑制花生侧根发生过程中的表达

Cloning of AhCYCB1 Gene and Its Expression during Lateral Root Formation Inhibited by ABA in Peanut (Arachis hypogaea L.)

根据水稻、拟南芥和玉米等植株的CYCB基因序列设计引物,以花生根系成熟区总RNA逆转录得到的cDNA为模板,用PCR扩增克隆花生CYCB1基因片段,命名为AhCYCB1(GenBank登录号为GQ868755)。该基因编码的蛋白具有CYCB1蛋白序列的特征区,与拟南芥的AtCYCB1蛋白聚类关系最近。半定量RT-PCR分析表明,ABA处理后,侧根起始部位的AhCY-CB1基因表达水平降低,ABA合成抑制剂萘普生(naproxen)处理使AhCYCB1基因表达水平明显上调。推测ABA抑制侧根发生与其降低侧根发生部位由G2期进入M期的细胞数目有关。

A peanut （Arachis hypogaea） CYCB1 gene, named AhCYCB1 （GenBank accession number： GQ868755）, was cloned from peanut root using a pair of primers, which were designed according to the homologous sequences in Arabidopsis thaliana, Oryza sativa and Zea mays. Comparative primary structure analysis of the deduced AhCYCB1 with CYCBs from other species identified a conserved domain that the CYCB family contains. Phylogenetic tree analysis indicated that the AhCYCB 1 protein had the closest relationship with AtCYCB1 proteins from A. thaliana plants. The expression of AhCYCB1 in the mature roots of peanut seedlings treated with abscisic acid （ABA） was inhibited by semi-quantitative RT-PCR, while seedlings treated with naproxen, an ABA biosynthesis inhibitor, caused an increase in AhCYCB1 expression. Taken together, the reason for ABA inhibiting lateral root formatiorn in peanut involved a decrease in cell number during the G2/M transition.