Chi-miR-370-3p Regulates Hair Follicle Morphogenesis Of Inner Mongolian Cashmere Goats

MicroRNAs(miRNAs),a class of 22 nucleotide(nt)non-coding RNAs,negatively regulate m RNA post-transcriptional modification in various biological processes.The landmark events of cashmere follicle morphogenesis are epithelial cells,dermal fibroblast formation placode(PC)and dermal condensate(DC).This is a dynamic process involving many key signalling molecules,but the associated cellular biological mechanisms induced by these key signalling molecules have not been reported.In this study,the differential expression analysis and bioinformatics analysis of temporal expression analysis of miRNAs in skin tissue of cashmere goats at different embryonic stage constructed by the research group were carried out.The key miRNAs and their target genes related to the formation of PC and DC in Inner Mongolia cashmere goats were screened,the target relationship of miRNA and its target gene was identified by Quantitative real-time PCR(qRT-PCR)and dual luciferase reporting,qRT-PCR and Western blot were used to verify the regulatory effect of the miRNA on its target genes in epithelial cells and dermal fibroblasts,DNA staining,CCK8 staining,Annexin V-FITC/PI double staining and cell scratch test were used to detect the effects of miRNA on cell cycle,proliferation,apoptosis and migration of epithelial cells and dermal fibroblasts.The main results were as follows:1.chi-miR-370-3p is a key miRNA in hair follicle morphogenesis of Inner Mongolia cashmere goat;qRT-PCR and dual luciferase reporting results showed that TGF-βR2 and FGFR2 were the target genes of chi-miR-370-3p.2.The results of qRT-PCR and Western blot showed that chi-miR-370-3p negatively regulated TGF-βR2 and FGFR2 at m RNA and protein levels in epithelial cells and dermal fibroblasts.3.The results of DNA staining and CCK8 showed that chi-mir-370-3p could increase the proportion of G0/G1 in the cell cycle of epithelial cells and dermal fibroblasts,and inhibit cell proliferation.Annexin V-FITC/PI double staining showed that chi-miR-370-3p had no significant effect on apoptosis of epithelial cells and dermal fibroblasts.4.Chi-miR-370-3p enhances the migration of epithelial cells and dermal fibroblasts by targeting TGF-βR2 and FGFR2.