Study of differential gene expression of Holstein cow’s fertility in corpus luteum using RNA-Seq data

The fertility of female cows is the main factor for the survival of dairy farming. This study was performed to determine the differentially expressed genes in fertility in Holstein cows using phenotypic data and next-generation sequencing (NGS) technology. Corpus luteum samples from 18 Holstein cows at up to two parturitions were used in two high and low fertility groups, three samples from each group were pooled together and a total of three biological samples from each were submitted for whole genome sequencing. The preparation and analysis steps were performed on the Galaxy 22.01 platform. DAVID (2021) database were used for gene ontology. The results of differential gene expression analysis in luteal tissue showed that 19 genes out of 13049 expressed transcripts had a significant difference in expression between high and low-fertility cows with an FDR-adjusted p-value (q-value) of less than 0.05. UBE3B, NIF3L1 and ORC2 genes were three functional marker genes that were more highly expressed in the corpus luteum of high-fertility cows. The UBE3B gene is involved in biological processes as a protein involved in the catabolic process of ubiquitin-dependent protein. NIF3L1 is involved in the biological process of neuronal differentiation, positive transcriptional regulation, DNA pattern, and negative transcriptional regulation by nucleic acid pattern. The ORC2 gene plays a role in the biological process of DNA replication. The genes KRT8, PHLDB3, PPT2, LOC787628, PPYR1, TOX, TP73, DHX8, KCNN1, CLEC6A, PXMP4, LRRC26, SLC34A3, and OR13C7 have been shown to be more highly expressed in the corpus luteum in low fertility cows. Among these genes, three genes PPT2, PPYR1 and CLEC6A were functional indicators. The loci UBE3B, NIF3L1 and ORC2, which were expressed more strongly in the corpus luteum of highly fertile cows, can be used as functional indicator genes in the genetic selection of dairy cows.