Proteoma de folículos antrais iniciais e cultivo in situ em pequenos ruminantes

Abstract

The present thesis had two objectives: 1) to describe the proteome of ovine early antral follicles using mass spectrometry associated with liquid chromatography (Study 1). 2) to describe the proteome of goat ovarian tissue cultured in minimal essential medium (α-MEM) (Study 2). In study 1, follicles were isolated from the ovarian cortex at an early stage of antrum formation and separated for protein extraction, followed by tryptic digestion, desalination, and peptide analysis by LC-MS/MS. In this follicular category, 2,503 proteins were identified, which vimentin, lamin, actin, heat shock chaperone proteins and histones were confirmed as the most abundant ones. Data were analyzed with bioinformatics tools according to gene ontology, protein clustering, protein-protein interaction, metabolic pathways and miRNAs. The identified proteins were mainly related to translation pathways and clusters, metabolic processes, phosphorylative oxidation, oocyte meiotic division, among others. They are mainly present in the processes of binding and expression of genes involved in cellular processes (cycles, division, differentiation and cell death), aging and differentiation of adipocytes. This study provides the first characterization of the proteome of early antral follicles from sheep, which it was possible to identify proteins and pathways associated with the folliculogenesis process. For study 2, ovarian tissue from goats were cultured in minimum essential medium for seven days and then subjected to protein extraction, tryptic digestion, desalination and peptide analysis by LC-MS/MS. In this study, 2,157 proteins were identified, which the most abundant were extracellular matrix proteins. As in the first study, the data were analyzed with the aid of bioinformatics tools according to gene ontology, protein clustering, protein-protein interaction, metabolic pathways and miRNAs. Cellular components, protein clusters and biological processes indicate the action and presence of pathways related to protein folding, RNA metabolism, RNA splicing and other pathways linked to collagen metabolism, one of the most important protein found in this study. Furthermore, miRNAs indicate functions associated with cellular processes, angiogenesis, hematopoiesis and cellular aging. This study provides a detailed description of the proteome of goat cultured ovarian tissue.