Transcriptomic Pattern of Genes Regulating Protein Response and Status of Mitochondrial Activity Are Related to Oocyte Maturational Competence—A Transcriptomic Study

Abstract

This paper aims to identify and describe new genetic markers involved in the processes of protein expression and modification reflected in the change of mitochondrial activity before and after in vitro maturation of the oocyte. Porcine oocytes collected from the ovaries of slaughtered landrace gilts were subjected to the process of in vitro maturation. Transcriptomic changes in the expression profile of oocyte genes involved in response to hypoxia, the transmembrane protein receptor serine threonine kinase signaling pathway, the “transforming growth factor β receptor signaling pathway”, “response to protein stimulus”, and “response to organic substance” were investigated using microarrays. The expression values of these genes in oocytes was analyzed before (immature) and after (mature) in vitro maturation, with significant differences found. All the significantly altered genes showed downregulation after the maturation process. The most changed genes from these gene ontologies, FOS, ID2, VEGFA, BTG2, CYR61, ESR1, AR, TACR3, CCND2, CHRDL1, were chosen to be further validated, described and related to the literature. Additionally, the mitochondrial activity of the analyzed oocytes was measured using specific dyes. We found that the mitochondrial activity was higher before the maturation process. The analysis of these results and the available literature provides a novel insight on the processes that occur during in vitro oocyte maturation. While this knowledge may prove to be useful in further research of the procedures commonly associated with in vitro fertilization procedures, it serves mostly as a basic reference for further proteomic, in vivo, and clinical studies that are necessary to translate it into practical applications.

Analysis of expression of genes responsible for regulation of cellular proliferation and migration – microarray approach based on porcine oocyte model

“…This gene can also cause cell apoptosis. Therefore, the suppressed expression of this gene in the ooze can indicate that oocytes don't differentiate during puberty and do not show the need for apoptosis [27]. Such conclusions coincide with the literature data.…”

New molecular markers involved in immune system homeostasis and hemopoietic organ development are differentially regulated during oocytes in vitro maturation

“…The Id proteins (1)(2)(3)(4) in general control lymphocyte development and homeostasis through their inhibitory effect on helix-loop-helix (HLH) DNA transcription factors [14]. Our results for ID2 downregulated expression in the oocyte after IVM is supported by Chermuła et al's own study [15], which may indicate a role in the development and maturation of the oocyte.…”

Development and validation of a genomic nomogram based on a ceRNA network for comprehensive analysis of obstructive sleep apnea

“…In conjunction with the expression level and correlation analysis of hub genes, as well as the PPI network diagram and its significance, the number of candidate variables was reduced to 4 potential predictors (CCND2, WT1, E2F2, and IRF1). It has been reported that CCND2 regulates cell proliferation by binding to cyclin-dependent kinase 4 (CDK4) or cyclin-dependent kinase 6 (CDK6) to form a complex required for the G1/S cell cycle (Chermuła et al, 2019). Furthermore, it has been reported that CCND2 is one of the most important biomarkers of endothelial dysfunction (Zhu et al, 2021).…”