EDAR参与绵羊毛发性状与生长的调节

绵羊的背部、耳部和腹股沟部的毛发性状、生长速度存在差异，背部毛发弯曲、细长、密度高、生长速度快，耳部、腹股沟部毛发粗直、密度低、生长速度慢。研究表明，EDA/EDAR、IGFBP5/Krox 20、WNT等介导的信号通路及毛发角蛋白基因对毛发纤维弯曲的形成有重要的影响。本研究利用实时荧光定量PCR、原位杂交技术、Western 印迹和免疫组织化学等技术，对外异蛋白受体（ectodysplasin A receptor，EDAR）在绵羊背部、耳部和腹股沟皮肤中的mRNA、蛋白质表达水平和定位进行研究，以探讨EDAR与绵羊毛发的生长和性状的关系。实时荧光定量PCR结果显示，EDAR在绵羊背部皮肤中相对基因表达量是绵羊腹股沟皮肤的4.9倍(P＜ 0.01),耳部是腹股沟部的1.4倍（P＜0.05），背部是耳部的3.4倍（P＜0.05）；原位杂交和免疫组化结果表明,EDAR基因mRNA和蛋白质在背部、耳部和腹股沟部毛囊均有表达。根据光密度值可知,背部表达量最高,耳部次之,而腹股沟部最低；Western 印迹结果显示，绵羊皮肤组织蛋白质提取物中存在与兔抗EDAR多克隆抗体发生免疫阳性反应的蛋白条带，绵羊皮肤背部平均蛋白质表达量最高,耳部次之,而腹股沟部最低，差异极显著(P ＜ 0.01)。研究结果提示，EDAR可能参与绵羊毛发卷曲的形成和调控,对毛发密度、生长速度等可能也有影响。

EDAR is Involved in the Regulation of Sheep Hair Characters and Growth

There are differences on hair traits and growth rate in back, ear and groin of sheep. The back hair is more bending, long and thin, high density, grows faster than the ear and groin hair. Some study showed that the signaling pathways of EDA/EDAR, IGFBP5/Krox 20, WNT and hair keratin genes have important influence on the formation of hair fiber bending. In order to investigate sheep ectodysplasin A receptor（EDAR）relationship with hair growth and character, the mRNA and protein levels of sheep EDAR were determined in back, ear and groin by real-time PCR,in situ hybridization, Western blot and immunohistochemistry. The real-time PCR results showed EDAR relative gene expression level of back was 4.9 fold higher than that of groin(P＜0.01), ear was 1.4 higher than that of groin（P＜0.05）, and back was 3.4 fold higher than that of ear（P＜0.05）.The in situ hybridization and immunohistochemical results showed EDAR mRNA and protein were expressed in sheep back, ear and groin hair follicles, and the expression amount followed by back, ear and groin. Western blot results showed the distribution of EDAR in sheep skin were demonstrated，and the expression amount was notable followed by back, ear and groin. The results suggested that EDAR might be involved in the formation and regulation of sheep curly hair, and also has an impact on hair density, high growth rate.