蒺藜苜蓿MtCKX基因功能的初步鉴定

摘要

采用 RT-PCR法克隆了蒺藜苜蓿MtCKX 基因,基因编码区长 1635bp,编码 544 个氨基酸.生物信息学分析表明,其编码的蛋白与其他物种CKX蛋白具有较高的同源性,与鹰嘴豆的同源性最高.荧光定量分析结果表明,MtCKX 基因在蒺藜苜蓿叶片中的表达量最高.此外,MtCKX 基因还响应 IAA、6-BA 的诱导.成功构建了35 S::MtCKX:YFP 植物表达载体,亚细胞定位分析表明,MtCKX 定位于细胞膜和细胞核.过表达的蒺藜苜蓿MtCKX 基因可导致转基因拟南芥中细胞分裂素含量显著降低.%CKX,a key factor that manipulates plant endogenous cytokinin content,is considered as the target gene that regulates crop yield and resistance.MtCKX was cloned by RT-PCR from Medicago trun-catula.The coding domain sequence was 1635bp in length,encoding 544 amino acids.Based on bioinforma-tic analysis,MtCKX showed highly homologous characteristics with other CKX family genes,especially homologous with CKX from Cicer anetinum.Quantitative Real-time PCR showed that the expression of MtCKX was highest in the leaf blade.MtCKX was responsive to the induction of IAA and 6-BA.CKX gene was inserted into 3302Y plasmid to construct the plant expression vector 35S::MtCKX:YFP.Subcel-lular localization analysis showed that MtCKX localized in the membrane and nucleus.Over expression of MtCKX gene resulted in a significant decrease in cytokinin content in transgenic Arabidopsis thaliana.