棉花转录因子基因GhMS3的克隆及其启动子功能的鉴定

Cloning and Promoter Function Identification of Cotton Transcription Factor GhMS3

【目的】从棉花无短绒突变体GZnn中分离棉纤维发育相关的转录因子,并对其转录激活功能和表达模式进行初步分析。【方法】通过RACE(rapid amplification of the cDNA ends)和染色体步行(genome walking)技术,获得GhMS3的cDNA序列及基因组DNA序列。利用生物信息学方法对获得的DNA序列及推定的氨基酸序列进行分析,采用酵母单杂交系统验证GhMS3蛋白的转录激活功能,运用GUS组织化学染色法在转基因烟草中分析该基因的表达模式。【结果】获得GhMS3的基因组DNA以及上游1174bp的启动子序列。氨基酸序列比对发现GhMS3是R2R3 MYB转录因子。酵母试验表明,GhMS3蛋白具体外转录激活功能,C端体外转录激活功能较强,在PGhMS3:GUS转基因烟草中,GUS主要在表皮毛、根毛以及细胞分裂旺盛区域表达。【结论】从棉花无短绒突变体GZnn中分离到的R2R3 MYB转录因子GhMS3,具有组织特异性表达模式并且其编码蛋白具有体外转录激活功能,是否参与植物表皮细胞分化有待于进一步研究。

【Objective】 This study aims to isolate a new transcription factor related to cotton fiber development from the fuzzless cotton mutant GZnn and investigate its transcriptional activation and expression pattern in PGhMS3：GUS transgenic tobacco plants.【Method】 GhMS3 cDNA and genomic DNA sequences were obtained by RACE（rapid amplification of the cDNA ends） and genome walking.Bioinformatics methods were used to analyze the DNA and the encoded amino acid sequence.The transcriptional activation in yeast cells and the expression pattern in PGhMS3：GUS transgenic tobacco plants were analyzed,respectively.【Result】 The full length of GhMS3 genomic DNA and a 1 174 bp upstream region were isolated.GhMS3,analyzed by amino acid alignment,was a R2R3 MYB transcription factor.Yeast one-hybrid assay showed that the C terminus of GhMS3 had strong expression in trichomes,root hairs,and actively dividing cells of PGhMS3：GUS transgenic tobacco plants.【Conclusion】 GhMS3,a R2R3 MYB transcriptions factor gene cloned from fuzzless cotton mutant GZnn,was specifically expressed during ovule development of GZnn and in actively dividing cells in PGhMS3：GUS transgenic tobacco plants.GhMS3 had transcriptional activation in vitro.Further function analysis of GhMS3 in plant cell differentiation is undergoing.