Slc7a11 基因属于溶质转运家族, 编码胱氨酸/谷氨酸xCT 转运载体, 经证实该基因调控黑色素与伪黑色素的转换。文章利用实时荧光定量PCR技术分析Slc7a11基因在3种不同毛色哈萨克绵羊羔羊皮肤组织中的mRNA转录水平, 构建原核表达载体, 诱导表达融合蛋白, 并对包涵体蛋白进行纯化, 免疫新西兰大白兔制备抗血清, 最后检测不同毛色皮肤中该蛋白的表达水平。结果表明, Slc7a11基因在3种毛色皮肤中的表达水平有显著差异, 棕色被毛皮肤中表达水平最高, 其次是黑色, 在白色中表达最少。利用纯化的融合蛋白制备多克隆抗体, 发现sxCT蛋白在棕色被毛中表达最高, 其次是黑色, 白色最低, 因此, Slc7a11 基因可能与哈萨克绵羊毛色表型有相关性。
Slc7a11 belongs to solute transporter gene family, encoding cystine/glutamate transporter xCT. It regulates switching between eumelanin and pheomelanin synthesis. In the present study, Real-time PCR was used to detect the mRNA expression levels of Slc7a11 in the skin of Kazakh lambs with different coat colors (black, brown and white), and then the prokaryotic expression plasmid PET-32a-sxCT was constructed to induce the expression of fusion protein. The target protein was purified by Ni-NTA affinity chromatographic separation, and then was used to immunize rabbit in order to produce rabbit anti-sxCT polyclonal antibody. Finally, the expression levels of sxCT were detected in the skin of Kazakh lambs with different hair colors by Western blotting analysis. Results showed that the mRNA expression levels of Slc7a11 differed significantly in the skin of Kazakh lambs with different coat colors, with the highest level in brown coat color, followed by the black, and then the white. The sxCT protein was also detected in the skin of different coat colors by polyclonal antibody, with the highest level in brown coat color, followed by the black, and then the white. It is, therefore, concluded that slc7a11 gene might be associated with the phenotype of coat color in Kazakh sheep.
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