摘要： 以甜高粱品种Roma为试验材料,在生物信息学分析基础上,采用逆转录-聚合酶链式反应(RT-PCR)方法,克隆了SbAGL6基因的编码区序列。序列分析表明,SbAGL6基因编码具有256个氨基酸的转录因子,在其N端含有MADS-box结构域,中间存在K-box结构域,与拟南芥AtAGL6等直系同源基因在核苷酸和氨基酸序列上都有较高的相似性。为验证其生物学功能,采用Gateway的方法,构建了SbAGL6基因的可诱导过表达载体。利用农杆菌介导侵染拟南芥的方法,获得了SbAGL6基因的转基因拟南芥植株,并对其进行了功能鉴定。结果表明,未施加诱导物地塞米松Dex时,转基因拟南芥与野生型生长一致,而施加DEX后,转基因植株比野生型提早开花,SbAGL6基因在调控植物花期转换中发挥了作用。

关键词: 高粱, SbAGL6, 拟南芥, 花期转换

Abstract: Floral transition is a crucial stage for establishment of life cycle and agronomic traits in sorghum. But the mechanism underlying this biological process remains largely elusive. In this study, we cloned the coding sequence of putative SbAGL6 genes from sorghum cultivar, Roma, by in silico sequence analysis and reverse-tran- scription PCR. The DNA sequence alignment revealed that SbAGL6 gene encoded a transcription factor with 256 ami- no acids which included a MADS-box domain in the N-terminal and a K-box domain in the middle. SbAGL6 gene shared high sequence similarity with AtAGL6 gene,indicated the functional similarity between two genes. To clarify the biological functions of SbAGL6 gene,we constructed an inducible over-expression vector for SbAGL6 based on Gateway cloning technology,and transformed SbAGL6 over-expression cassette into Arabidopsis plants. The phenotypic analysis demonstrated that transgenic plants flowered earlier than the wild type after application of inducer Dexamethasone (Dex) . But transgenic plants would show no difference from wild type plants under mock treatment. These results sup- ported our proposition that SbAGL6 gene might play an important role in controlling flowering time in sorghum.

Key words: Sorghum, SbAGL6, Arabidopsis thaliana, Floral transition

中图分类号: 

• S514