Integrated analysis of transcriptomes and proteomes reveals the molecular mechanisms underlying the development of Dorper sheep hair follicles.

Understanding the molecular mechanisms underlying normal hair follicle development is important for improving wool traits in sheep and skin traits in mammals. This study aims to investigate the genetic determinants influencing hair follicle (HF) development by conducting an integrated analysis of transcriptomic and proteomic datasets from skin tissues of adult Dorper ewes at different groups of shedding and non-shedding. We employed DIA quantitative proteomics technology to identify 2176 differentially abundant proteins (DAPs) across three stages in both the shedding and non-shedding groups. Six DAPs were validated using parallel reaction monitoring (PRM) to confirm the reliability of the discovery proteomics data. Functional enrichment analysis revealed that a series of biological processes and signaling pathways associated with HF development, such as glutathione metabolism, ferroptosis, Wnt, JAK-STAT, and PI3K-Akt pathways, were strongly enriched by these DAPs. Association analysis and protein interaction network analysis further indicated that ACTG1, ANPEP, CTNNB1, GCLC, GCLM, CSNK2A2, COL1A1, GLUL, VTN, CDK6, IKBKG, STAM2, ITGA3, and members of the keratin (KRT) family may be key factors contributing to the developmental differences in the hair follicle cycle. Our study contributes to the understanding of the genetic and proteomic mechanisms underlying the normal growth and development of hair follicles and mammalian skin-related traits. SIGNIFICANCE: The morphology of secondary hair follicles in Dorper sheep plays a crucial role in determining the hair follicle cycle. The hair follicle cycle, as well as hair follicle growth and morphogenesis, are coordinated and complex processes. This study constructed a protein regulatory network within the signaling pathways associated with the cyclic growth and development of Dorper sheep hair follicles, and investigated key genes whose expression levels were positively correlated between mRNA and protein. Understanding the genetic mechanisms underlying the hair-shedding ability of Dorper sheep is crucial for enhancing the economic value of meat sheep and advancing the breeding of automatically hair-shedding sheep.