中文摘要：

MC1R基因与黑色素细胞的功能、皮肤的色素沉着和皮肤癌风险相关。本研究MC1R基因在不同毛色绵羊皮肤组织中的差异表达及定位,以探索MC1R基因对皮肤色素生成方面的重要作用,确定其与毛色形成的相关性。采用荧光定量PCR方法和免疫印迹方法分别检测不同毛色绵羊皮肤中MC1R基因m RNA水平和蛋白水平的表达差异;运用免疫组织化学法对不同毛色绵羊皮肤组织中的MC1R基因进行定位。荧光定量PCR结果显示MC1R m RNA在所有绵羊皮肤组织中都表达,在全黑绵羊皮肤中的相对表达量为537.91±150.36＊＊,在花黑和花白绵羊皮肤中的相对表达量分别为27.95±9.3＊＊和4.19±0.57＊＊,而在全白绵羊皮肤中的相对表达量为1.03±0.27;免疫印迹结果显示所有绵羊皮肤组织蛋白中均存在与MC1R反应的阳性条带,MC1R在全黑绵羊皮肤组织中的相对蛋白含量为6.3±0.21＊＊,在花黑和花白绵羊皮肤组织中的相对蛋白含量分别为2.74±0.24＊＊和1.55±0.1＊＊,而在全白绵羊皮肤组织中的相对蛋白含量为1±0.15;免疫组织化学结果显示MC1R蛋白主要表达部位为绵羊皮肤组织毛囊的基质、根鞘等区域。试验表明不同毛色绵羊皮肤组织均正常表达MC1R基因,但其表达水平存在差异,全黑绵羊皮肤中MC1R m RNA和蛋白的表达量显著高于其它三种毛色绵羊,综上可知MC1R基因影响绵羊黑白花毛色的形成,而且真黑素的合成依赖于MC1R的表达水平。

英文摘要：

MC1R is associated with melanocyte function, skin pigmentation and skin cancer risk. This study investigates the differences of MC1R expression and localization in sheep skin with different coat colors and explores the important role of MCIR in the pigmentation of skin and then determines its correlation with coat color formation. The relative expression levels of MC1R mRNA and protein in sheep skin samples with different coat colors were qualitatively and quantitatively analyzed by qRT-PCR assay and immunoblotting, respectively. The immunohistochemistry assay was to detect the location of MCIR in the skin of sheep with different coat colors. The qRT-PCR analysis revealed that MC1R mRNA was expressed in all sheep skin samples tested, with relative expression levels of 537.91±150.36＊＊ in black skin, 27.95±9.3＊＊ and 4.19±0.57＊＊ in black dots and white dots of piebald skin, respectively, and 1.03±0.27 in white skin. Positive MC1R protein bands were also detected in all skin samples by immunoblotting analysis, with relative expression levels of 6.3±0.21＊＊ in black skin, 2.74±0.24＊＊ and 1.55±0.1＊＊ in black dots and white dots of piebald skin, respectively, and 1±0.15 in white skin. Immunohistochemistry assay showed that MCIR was primarily expressed in the root sheath and Hair follicle matrix of sheep skin tissues. Here, we demonstrate that MCIR is normally expressed in sheep skin of all coat colors, though at different levels. The expression level ofMCIR mRNA and protein in black sheep are significantly higher than that in others, which indicate that MCIR affect the formation of coat color with black and white in sheep, and the eumelanin biogenesis is depend on the expression level of MCIR.