Expression Pattern And Function Analysis Of Hoxc13 Gene In Skin Of Cashmere Goat

Cashmere goat is a very important economic animals provided wool and cashmere. Coat hair growth can be affected by many factors. Hoxc13 has an important role in controlling hair formation through regulating keratin differentiation-specific genes. Hoxc13 deficient and overexpressing mice exhibit severe hair growth and patterning defects. Therefore, we detected the expression level of Hoxc13 in cashmere goat skin from different developmental phases of hair follicle; and investigated the effect and interaction relations for over-expression Hoxc13 and other HFDRGs of skin cells in vitro; and clarified the role of melatonin with relation to HFDRGs by analyzing the changes of HFDRGs expressing between melatonin implant/add and control.The following conclusions were obtained from the study.1. In this study, the Hoxc13 gene of cashmere goat was cloned (Assession number: EU839660), The gene spans 7.2 kilobases (kb) and has two exon which seperated by a relatively large intron, which has a coding sequence of 990 nucleotides that putative 330 amino acids. By analyzing the protein sequence of Hoxc13 in 28 species of vertebrates which belonged to 3 classes and 17 orders, we found that an insertion of low complexity region(LCR) in N teminal of Hoxc13 during the divergence of the therapsid lineage (leading to mammals) from the sauropsid lineage (reptiles, birds). The divergence of length of the LCR occurs in mammal(10-28Aa). Our results implicate adaptive evolution of Hoxc13 genes occurs in the origin and diversification of the mammals.2. The changes of the Hoxc13 gene expression and thickness of skin have a similar trend during hair follicle morphogenesis. In adult goat, the expression level of Hoxc13 in skin associated with the follicle activity. Melatonin may get to expression cycle of Hoxc13 in cashmere goat skin in advance, and the expression level of the Hoxc13 was significantly increased during 8-10 month. In vitro, melatonin has a diversity effect to fibroblasts and keratinocytes. It could increase the expression level of Hoxc13 in keratinocytes, while inhibit the Hoxc13 expression in fibroblasts.3. Overexpression Hoxc13 in keratinocytes could result in differentiation or die. Thus, we did not obtain the cell line that stablily expressed Hoxc13. However, a fibroblast cell lines with stable gene expression Hoxc13 was established. Overexpression Hoxc13 in fibroblasts of cashmere goat skin up-regulated Tgf?rII, Ror?2, Nanog, Wnt10b and PdgfrA, and down-regulated Bmp2, Msx2, Ntrk3 and Detal.In summary, adaptive evolution of Hoxc13 gene occurred in the origin and diversification of the mammalian coat hair. And Hoxc13 played an impotant role in goat skin and hair follicle morphogenesis/cycle by in vivo and in vitro researching. This study lay a fundation to further research on cashmere goats and other wool animals for developing mechanism of the hair follicle.