RNA-seq Transcriptome Analysis in Ovarian Tissue of Pelibuey Breed to Explore the Regulation of Prolificacy

Abstract

The Pelibuey sheep (Ovis aries) is an indigenous breed distributed in the tropical regions of Mexico. The prolificacy of this sheep is on average from 1 to 1.5 lambs, being an important breeding characteristic that owners seek to increase with the purpose of economic improvements. New-generation RNA sequencing technology has been used to identify the genes that are expressed in the ovarian tissue of sheep that have two or more lambs per parturition, as well as to elucidate the metabolic pathways that are affected by the expression of these genes, with the purpose of better understanding the prolificacy in the sheep. In the present study, the transcriptional expression of multiparous and uniparous sheep was compared using RNA sequencing. Multiparous (M group) and uniparous (U group) sheep that had a genealogical record for three generations (M, n = 5 and U, n = 5) were selected. RNA was extracted from ovarian tissue and subsequently used to prepare the libraries that were sequenced using the Illumina NextSeq500 platform. A total of 31,575 genes were detected from the transcriptomic analysis of which 4908 were significantly expressed (p-value ≤ 0.001) in the ovary of sheep. Subsequently, a second filter was carried out to evaluate the false discovery rate (FDR) and select those genes with p-values ≤ 0.05 and values of expression ≥ 1 (log2), obtaining 354 differential expressed genes (DEG): 120 genes up-regulated and 234 genes down-regulated in the group M with respect to the group U. Through Gene Ontology (GO) and metabolic analysis, we obtained information on the function of differentially expressed genes, and its importance in the reproduction of multiparous sheep. This result suggest that genes identified in the present study participate in the development of the final stages of follicles.

Gene Expression Profiling of Corpus luteum Reveals Important Insights about Early Pregnancy in Domestic Sheep

“…However, there are no reports regarding the expression and function of CA5A in the CL. Based on the results from our current and earlier reports [13,95], CA5A appears to have an important function, at least until the preimplantation stage of reproduction. The level of expression in F1 crosses in the CL followed the same pattern as that in the ovary, which led us to conclude that CA5A is heritable and potentially an imprinted gene.…”

“…In a previous study, we observed downregulation of CA5A in the ovaries of Texel compared to F1 [13]. More recently, CA5A was also shown to be expressed in the ovaries of the Pelibuey breed of sheep; the gene was upregulated in a subset of ewes that gave birth to two lambs compared to uniparous animals [95]. However, there are no reports regarding the expression and function of CA5A in the CL.…”

Genome-wide association study and pathway analysis identify NTRK2 as a novel candidate gene for litter size in sheep

“…Notably, the PI3K-Akt signaling pathway (oas04151) was one of our identified KEGG pathways with 21 significant genes, but it was not significant overall. Recently, using RNA-seq analysis, the PI3K-Akt signaling pathway was reported as a significant KEGG term affecting prolificacy [ 49 ].…”

“…cGMP) to support the oocyte development, metabolism, and hemostasis [ 79 ]. Many genomics, transcriptomics, and proteomics studies reported many pathways related to both cell adhesion and gap junction process as pathways which has vital roles in prolificacy [ 49 , 62 , 77 , 80 , 81 ].…”

Improving the Effects of Omega-3 Fatty Acid on the In Vitro Maturation of Oocytes

“…Fatty acids involved in maturation of oocytes can regulate expression level of genes associated with oocyte maturation (Veshkini et al 2016;Virant-Klun et al 2013). Recently, certain gene expression profiles have been studied and the findings indicate that oocyte maturation and follicular growth involve the expression of a number of genes including Tribbles (TRIB) genes (Hernández-Montiel et al 2019;Lussier et al 2017;Brisard et al 2014). However, TRIB genes have been less studied and the modulation of their expression during oocyte maturation is somehow unclear.…”