中文摘要：

【目的】研究酪氨酸酶（tyrosinase,TYR）在不同毛色羊驼皮肤组织中的表达与定位,为揭示羊驼被毛颜色形成的机制奠定基础。【方法】采用半定量RT-PCR方法检测TYR mRNA在不同毛色羊驼皮肤组织中的相对表达量,采用免疫组织化学技术对TYR在羊驼皮肤中的表达进行定位。【结果】不同毛色羊驼皮肤组织中均有TYR基因mRNA的表达,有色被毛皮肤组织中TYR的基因mRNA表达量显著高于白色被毛组织的表达量;在有色被毛皮肤组织中,TYR阳性反应区主要集中于毛球部位,即毛根成形部;而白色被毛组织中,TYR阳性反应区主要位于毛根壶腹部及膨大部,即毛根永久部。【结论】综合分析TYR基因mRNA表达量及蛋白定位结果可知,TYR是成熟黑色素细胞的标记分子之一,羊驼毛色形成取决于成熟黑色素细胞在毛囊组织中的相对数量及分布部位。

英文摘要：

【Objective】 The objective of the experiment is to study the expression and localization of tyrosinase in skin of alpacas with different coat colors,and to explore the mechanism of alpaca coat color formation.【Method】 The mRNA expression level and localization of tyrosinase were examined by semi-quantitative PCR and immunohistochemistry.【Result】 The gene expression quantity of tyrosinase in the skin of pigmented alpaca was higher than that of natural white alpaca.The distribution of tyrosinase in alpaca skin was demonstrated.The positive expression was mainly focused in hair bulb（transient portion） in pigmented coat color skin.However,in natural white coat color skin,the positive expression was mainly located in the hair bulge and enlargement（permanent portion）.【Conclusion】 Tyrosinase is one of the molecular markers for mature melanocyte.The experimental results show that coat color formation of alpacas is mainly determined by the amount and distribution of mature melanocytes in hair follicles.