Studies On The Follicle Morphology,Genes Related To Cycle And Synthesis Of Melanin In Mongolian Horse Skin

The hair follicle is a skin appendage providing physical barrier to protect mammals from external stimuli.Although the hair follicle is very small,its intermal structure is pretty complex.Hair growth and pigment synthesis in mammals are regulated by various factors inside the hair follicle.In this paper.Mongolian horse was used as experimental material adopting molecular biology means to preliminarily explore the morphological structure of Mongolian horse hair follicle,the periodic change of morphological structure,the expression of genes in different period,the distribution of melanin at different hair colors in hair follicle,and the expression of genes related to pigment synthesis by means of molecular biology.1.Mongolian horse hair follicle morphology:Morphological structure of Mongolian horse hair follicle was revealed and histological section method was used.The Mongolian horse hair follicle is composed of hair nipple,hair mother material,root sheath and hair stem.2.Effects of Sox2,DKK1 and CD34 genes on Mongolian horse hair follicle cycle:H&E staining showed that the hair bulb of Mongolian horse degenerated and moved towards the epidermis and the hair shaft fell off in Telogen.The morphology of hair bulb was enlarged,and the arrangement of Hair papilla and Hair matrix cells are regular in Anagen;The mRN A expressions of 3 genes were significantly different in different period skin tissues.Fluorescence quantitative PCR results showed that there was no statistically significant difference between the Sox2 gene in the Telogen and Anagen,the mRNA expression level of DKK1 gene Telogen was significantly higher than that Anagen(P<0.01),and the mRNA expression level of CD34 gene Anagen was significantly higher than that Telogen(P<0.05).Immunohistochemical results showed that Sox2 protein is localized in the root sheath and epidermis at the Telogen and in the root sheath at the Anagen.DKK1 protein is located in the root sheath and epidermis in the Telogen and epidermis in the Anagen.CD34 protein was located in the root sheath and epidennis in the Telogen and epidermis in the Anagen.3.Effects of TYR,TYRP1 and DCT genes on Mongolian horse hair color:It is obviously different that the distribution of pigment in black and white skin tissues.H&E staining showed that melanocytes were mainly located in the hair bulb and epidermis of black hair,while there is no melanocytes were observed in corresponding positions of white hair.The mRNA and protein expression levels of the three genes were significantly different in different skin tissues.The expression of TYRP1 and TYR genes in the skin tissue samples of black hair was significantly higher than that of white hair(P<0.001).The mRNA expression level of DCT gene showed no significant difference between the two groups.Western blot results showed that the relative expression of TYR protein in black hair was significantly higher than that in white hair.The relative expression of TYRP1 and DCT in black hair was slightly higher than that in white hair.Protein expression is mainly located in the maternal part of hair follicle and hair bulb.