FGF5在青年羊驼背部和耳部皮肤中的表达和定位

羊驼是毛用型经济动物，其耳部和背部的毛发品质和生长周期存在差异. 据研究成纤维细胞生长因子5（fibroblast growth factor 5, FGF5）在多种哺乳动物中影响毛发长度. FGF5基因的突变导致小鼠、狗和猫隐性的长发表型，其也参与了家兔绒毛长度的变异. 本实验旨在研究FGF5在青年羊驼皮肤中的表达和定位，以及在羊驼背部和耳部皮肤中的差异比较，探讨其在羊驼毛发生长发育过程中的作用及其相关机制. 实验采用实时荧光定量PCR、Western印迹和免疫组织化学等技术，对FGF5在青年羊驼背部和耳部皮肤中的mRNA、蛋白表达水平和定位进行了研究. 实时荧光定量PCR结果显示，FGF5在青年羊驼耳部皮肤组织中相对基因表达量是羊驼背部皮肤组织的25265倍(P<001); Western印迹结果显示，羊驼皮肤组织粗蛋白提取物中存在与兔抗FGF5多克隆抗体发生免疫阳性反应的蛋白条带，羊驼耳部皮肤平均蛋白表达量显著高于背部；免疫组织化学结果显示，FGF5在羊驼皮肤的毛根鞘，毛母质细胞和毛髓质等部位均表达，根据光密度值得出，该蛋白在羊驼背部和耳部皮肤中的表达差异极显著（P<001）. 试验结果提示FGF5可能抑制了羊驼毛发的生长.

FGF5 Expression and Immunolocalization in Back and Ear Skin of Young Alpaca (Lama pacos)

Alpaca (Lama pacos) is a fiber producing animal of commercial importance. The quality and growth of hair at the ear and back skin are different. The fibroblast growth factor 5 (FGF5) affects hair length in a diverse set of mammalian species. Mutations in FGF5 lead to recessive long hair phenotypes in mice, dogs and cats, and were implicated contributing to the hair length variation in rabbits. The aim of this study was to explore the function of FGF5 in the regulation of alpaca hair development and growth by comparing its expression and immunolocalization in the ear and back skin of young alpaca. The mRNA and protein levels of FGF5 were determined by real time PCR, Western blot and immunohistochemistry. The results showed that the FGF5 gene was expressed in alpaca skin reliably. The gene expression quantity of FGF5 in ear skin of alpaca was 25265 times than that in back. The distribution of FGF5 in alpaca skin were demonstrated, and the expression was notable difference between the ear and back skin of young alpaca based on the average optical density. Our findings showed that FGF5 might be involved in the regulation of hair development and growth of alpaca and might inhibit the hair growth in alpaca.