棉花类固醇5α-还原酶基因单核苷酸位点的变异效应

The Effect of DET2 Single Nucleotide Variation on Protein Structure and Fertility in Gossypium

为了明确棉花种质资源中类固醇5α-还原酶(Steroid 5 alpha-reductase,DET2)基因单核苷酸多态性,了解核苷酸位点变异对其编码蛋白配体结合域的影响并开发功能分子标记,本研究采用同源基因特异扩增、测序的方法,筛查不同棉花材料的DET2基因编码区突变,分析DET2基因编码蛋白质的三级结构及配体结合位点及其与纤维品质和育性的相关性。结果表明,包含陆地棉、海岛棉、雷蒙德氏棉在内的13份棉属材料DET2基因序列一致性为98.7%,编码区25个碱基易突变位点中有8个位点涉及编码氨基酸变化;该基因编码的蛋白二级、三级结构基本相似,但是配体结合位点差异较大;编码蛋白配体结合域共有8种类型,与品种间SNP组合类型完全相符。DET2基因与棉花纤维品质形成相关,但与育性无关。

This research aimed to investigate the effects of single nucleotide variation （SNVs） of the steroid 5 alpha-reductase gene（DET2） in cotton plants （Gossypium） on the ligand-binding domain of the coded protein, and to develop single nucleotide polymorphism （SNP） markers. The DET2 coding regions in Goss3oaium germplasm were amplified and sequenced. Multiple sequence alignment, and secondary and tertiary structure prediction of encoded proteins were carried out using sequence analysis software such as Geneious ProTM and online bioinformatics analysis tools. Models of protein tertiary structures, including ligand-binding domain, were established to explore the correlation between SNVs and cotton fiber quality, and lant fertility. Among the 13 stocks of upland cotton tested, together with island cotton and G. raimondii, DET2 demonstrated a high sequence conservation of 98.7%. A total of 25 SNVs were detected, of which eight resulted in changes to the amino acid sequence. Predicted secondary structure and tertiary struture were similar, although the ligand-binding sites could be classified into eight different types following protein sequence changes.