Screening Candidate Genes Of Cashmere Heterogeneity In Different Body Sites Of Cashmere Goats Based On Transcriptomics

Inner Mongolia White Cashmere Goat is an excellent breed with purpose of cashmere and meat.It is a valuable germplasm genetic resource in China.Therefore,it is of great significance to study the growth and development mechanism of cashmere and explore the candidate genes related to cashmere quality.In order to reveal the mechanism heterogeneity of cashmere in goat,this experiment preliminarily analyzed the cashmere quality of four sites of skin in Inner Mongolia White Cashmere goat from the phenotypic and transcriptome levels,the ewes with similar body weight,good physical condition and healthy body are selected,and cashmere and hair follicle samples from body side,back,abdomen and neck are collected,then measured the fleece traits and extract RNA.Further analysis of variance was used to illustrate the significant difference of fleece traits in different skin sites.At the same time,12 samples from four sites of three individuals were sequenced.Bioinformatics analysis was used to screen the differential expression genes of cashmere heterogeneity in different sites.Finally,three candidate genes were selected for q RT-PCR verification.The main results are as follows:1.A total of 180 records were collected from the side,back,abdomen and neck of 45 cashmere goats.The results showed that there was a significant difference in cashmere fiber diameter between different parts(P<0.01),but the Coefficient of variation of cashmere fiber diameter was not significant(P>0.05).The results of multiple comparison showed that the neck and back were the thinnest and the abdomen the thickest,which indicated that there were indeed differences in the cashmere traits of different parts.2.Transcriptome sequencing was performed on 12 hair follicle samples from four sites.According to the screening criteria of Padj < 0.05 & log2(foldchange)| > 0,total of 23 differential expression genes in 6 groups,including 2 up-regulated genes and 21 downregulated genes.Further gene prediction of transcripts showed that FOSB、KRT14、CA12、RASD1、CDSN、WNT4、AQP5、CAPN5、MAPRE2、ASAP1 and MATN2 may be candidate genes affecting cashmere heterogeneity in Inner Mongolia White Cashmere goat.Go functional gene enrichment analysis showed that the differential expression genes were mainly involved in Notch signal pathway,ERBB regulation,epidermal growth factor signal transduction,phenolic compound metabolism,epidermal growth factor receptor signal,and so on.The enrichment of KEGG pathway showed that the differential expression genes were mainly related to estrogen signaling pathway and ribosomal relaxin signaling pathway.3.The differential expression genes including AQP5,MATN2 and CA12 of cashmere heterogeneity in different sites of cashmere goat were verified by q RT-PCR.The results showed that there were significant differences in the relative expression of each gene among body side,back,abdomen and neck.The relative expression of the three genes was the highest in the abdomen,which was significantly higher than that in other sites.The relative expression of MATN2 and CA12 showed the same change trend in the four sites.The relative expression level showed as abdomen > body side > neck > back,which was consistent with the change rule of phenotype,indicating that they may be candidate genes for cashmere heterogeneity in different sites of cashmere goats.