The purpose of this study was to understand the effect of gender on the traits of wool. One-year-old male and female Chinese merino sheep (JunKen type) were used to screen differentially expressed proteins in skin tissues by quantitative proteomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and data independent acquisition (DIA) strategy. This was followed by GO function annotation, KEGG metabolic pathway and protein network interaction analysis on the differential proteins obtained. The result showed that there were 674 differentially expressed proteins between male and female groups, whereas 280 proteins were up-regulated and 394 proteins were down-regulated in the male group. Through further comparison and analysis, there were 43 differentially expressed proteins related to skin hair follicle development and wool phenotype, 30 up-regulated and 13 down-regulated. The GO annotation analysis of differentially expressed proteins were mainly enriched in 37 processes of molecular function such as oxygen binding, chondroitin sulfate binding, heme binding, glutathione peroxidase activity and glutathione transferase activity; 120 biological processes such as cellular oxidant detoxification, regulation of muscle contraction, notch signaling pathway, calcium ion transmembrane transport and glutathione metabolism; and 31 processes related to cellular components such as mast cell granule, nucleus, sarcoplasmic reticulum and endoplasmic reticulum lumen. KEGG analysis showed that the differentially expressed proteins were involved sixteen signaling pathways, among which MAPK and p53 signaling pathways were closely related to wool growth and development. The protein network interaction analysis discovered that COL1A1 was closely related to MMP2, SPARC, THBS1 and other differentially expressed proteins, which might play a key role in wool growth and development. Thus, this study obtained basic data for revealing the molecular mechanism of sheep wool traits of different gender.
Keywords: Chinese merino fine sheep (JunKen type); gender; proteomics; skin.