iProXProteomicsChunjie LiuOvis Arieshttp://www.iprox.org/page/project.html?id=IPX0016405000guilt369@163.comTarim UniversityiProXOvarian senescence is the fundamental cause of reduced fertility in female animals,however, the molecular characteristics of ovarian ageing in sheep remain insufficiently defined. In this study, ovarian tissues were collected from 12 Qira Black sheep and assigned to group D (1-2 years, <i>n</i> = 6) and group H (5-6 years, <i>n</i> = 6) for LC-MS/MS-based proteomic profiling. A total of 458 differentially expressed proteins (DEPs) were identified between the two groups, including 211 upregulated and 247 downregulated proteins. Functional enrichment analyses indicated that these DEPs were mainly involved in cell-cycle regulation, oocyte maturation, amino acid metabolism, and inflammation-related signalling pathways, with the Rat Sarcoma(Ras) and Mitogen-Activated Protein Kinase Pathway(MAPK) signalling pathways showing particularly strong enrichment. Protein-protein interaction (PPI) network analysis revealed close interactions among Intraflagellar transport 80(IFT80), Insulin receptor(INSR), Angiopoietin-like 4(ANGPTL4), Receptor interacting serine/threonine kinase 3(RIPK3), Nuclear receptor corepressor 1(NCOR1), and Fms-Related Tyrosine Kinase 4(FLT4), with Insulin receptor(INSR) occupying a central hub position. Collectively, this study establishes a differential proteomic atlas of ovarian ageing in Qira Black sheep, highlights the potential importance of Rat Sarcoma(Ras) and Mitogen-Activated Protein Kinase Pathway(MAPK) signalling in this process, and identifies Insulin receptor(INSR) as a candidate target, thereby providing a theoretical basis for subsequent mechanistic studies and the development of molecular markers.Proteomic analysis reveals key genes and pathways involved in ovarian ageing of Qira Black sheep.Guo Peilin P, Pei Linlin L, Liu Ningjie N, Wang Wenhao W, Qiao Andi A, Xu Xin X, Liu Chunjie CfalseProtein from ovarian tissue of Qira black sheepProteins were extracted from fresh and intact ovarian tissues, followed by sequencing analysisSat Mar 28 00:00:00 GMT 2026PXD076327994042453975