Granulosa cell transcriptomic study reveals the differential regulation of lncRNAs and mRNAs related to follicle development in goat

Abstract

Mammalian follicle development is a complex biological process regulated by several factors. More than 99% of the follicles in goat ovaries will be atresia and only a few will eventually mature and ovulate. To investigate the potential long noncoding RNAs (lncRNAs) that regulate the expression of genes associated with follicular dominance or atresia, RNA-seq was performed on dominant follicles (DFs) and subordinate follicles (SFs) of granulosa cells from goats at the first follicular wave.A total of 92 differentially expressed lncRNAs and 676 differentially expressed mRNAs were detected in both types of follicles. The qRT-PCR results were consistent with the transcriptome sequencing data. Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed mRNAs revealed that LHR and LDLR are associated with follicle dominance and are involved in the ovarian steroidogenesis pathway. The co-located mRNAs CALM2 and PPP1CA were significantly enriched during oocyte meiosis and in the cAMP and oxytocin signalling pathways.The co-expressed mRNAs were significantly enriched in the oestrogen signalling pathway and in ovarian steroidogenesis and progesterone-mediated oocyte maturation. A co-expression network of lncRNAs, target genes and differentially expressed genes was constructed. Follicle development-related genes, such as LDLR, NOTCH1 and FGF12, were included. These findings expand the lncRNA catalogue and provide a basis for further studies on the mechanism of regulating follicular development in goats.