10×Genomics Single-cell Sequencing Reveals Differential Cell Types in Skin Tissues of Liaoning Cashmere Goats and Key Genes Related Potentially to the Fineness of Cashmere Fiber

Abstract Cashmere fineness is one of the important factors determining cashmere quality, however, our understanding about the cells that make up the cashmere fineness is limited. Here, we used single-cell RNA sequencing (scRNA-seq) and computational models to identify 13 skin cell types in Liaoning Cashmere Goats. We also analyzed the molecular changes by Pseudo-Timeline Analysis in the development process and revealed the maturation process in gene expression profile in Liaoning Cashmere Goats. Weighted gene co-expression network analysis (WGCNA) explored hub genes in cell clusters related to cashmere formation. Secondary hair follicle dermal papilla cells (SDPCs) play an important role in the growth and density of cashmere. ACTA2, a marker gene of SDPCs, was selected for immunofluorescence (IF) and western blot (WB) verification. It was proved that it was mainly expressed in SDPCs, and WB results showed different expression levels. COL1A1 is a high expression gene in SDPCs, which was verified by IF and WB. Then select the function gene CXCL8 of SDPCs to verify, and prove the differential expression in the coarse type and the fine type of Liaoning Cashmere Goats. Therefore, COL1A1 may involve in regulated skin development and CXCL8 gene may regulate cashmere fineness. These genes may be involved in regulating the fineness of cashmere in goat secondary hair follicle dermal papilla cells, our research will provide new insights into the mechanism of cashmere growth and cashmere fineness regulation by cells.