Regulation Of Histone Methylation On The Regeneration Of Secondary Hair Follicle Stem Cells In Cashmere Goats

Cashmere comes from the secondary hair follicle of goat skin,which is formed by the differentiation of secondary hair follicle stem cells.The growth of secondary hair follicles is cyclical,and it has three cycles: anagen,catagen,and telogen.The purpose of this paper is to combine transcriptome with chromatin map to reveal the regulatory mechanism of key genes in the cycle growth of secondary hair follicle stem cells from DNA level to RNA level.Firstly,we isolated and cultured the secondary hair follicle stem cells of Liaoning Cashmere Goat and identified their purity;Secondly,m RNAs expressed during the growth of secondary hair follicle stem cells of cashmere goats were obtained by high-throughput transcriptome sequencing.Finally,thesecondary hair follicle stem cells were tested by Ch IP-seq of H3K27me3,H3K4me3,H3K36me3 and H3K79me2.The aim of this study was to investigate the molecular mechanism of secondary hair follicle stem cells in Liaoning cashmere goats and the regulation of histone methylation on the growth of secondary hair follicle stem cells.The main results of this study are as follows:(1)Isolation,culture and identification of the secondary hair follicle stem cells of Liaoning Capra hircus: two-step enzyme method and tissue attachment method were used to purify the secondary hair follicle stem cells in vitro.By observing the morphology and proliferation ability of cells,the results showed that the secondary hair follicle stem cells of Liaoning Cashmere Goat cultured in this experiment showed cobblestone like growth and high refraction,small cell morphology and several nuclei,strong cell adhesion.In conclusion,the secondary hair follicle stem cells cultured in vitro conform to the shape of hair follicle stem cells.The specific marker genes of hair follicle stem cells were identified.The results showed that the marker genes of hair follicle stem cells were highly expressed in the secondary hair follicle stem cells of Liaoning Cashmere Goat.Immunofluorescence analysis showed that the positive rate of krt14 was over 99.5% and the purity was high.In this experiment,the primary secondary hair follicle stem cells of Liaoning cashmere goat were successfully isolated and cultured.(2)Through RNA-seq and bioinformatics analysis,28921 m RNAs were obtained,among which 20441 RNAs were expressed.(3)Through RNA-seq and bioinformatics analysis,147 differential genes were found in the early and prosperous stages of anagen,of which 44 were up-regulated in the early stage of anagen;103were up-regulated in the prosperous stage of anagen,and the up-regulated gene function annotation in the early stage of anagen was related to the morphogenesis of hair follicles;the up-regulated gene function annotation in the prosperous stage was related to the maturity of hair follicles(4)The whole genome histone modification map of Liaoning Capra hircus secondary hair follicle stem cells was obtained by Ch IP-seq and bioinformatics analysis.(5)Through the Ch IP-seq of H3K27me3,H3K4me3,H3K36me3 and H3K79me2,it was found that histone modification signal affected gene expression,The expression level of the gene modified by H3K4me3 was higher;the expression level of H3K27me3 modified gene was lower.