Establishment of lncRNA-mRNA network in bovine oocyte between germinal vesicle and metaphase II stage.

Long non-coding RNA (lncRNA), a type of non-protein coding transcripts with lengths exceeding 200 nucleotides, is reported to be widely involved in many cellular and developmental processes. However, few roles of lncRNA in oocyte development have been defined. In this study, to uncover the effect of lncRNA during oocyte maturation, bovine germinal vesicle (GV) and in vitro matured metaphase II (MII) oocytes underwent RNA sequencing. Results revealed a wealth of candidate lncRNAs, which might participate in the biological processes of stage-specific oocytes. Furthermore, their trans- and cis-regulatory effects were investigated in-depth by using bioinformatic software. Functional enrichment analysis of target genes showed that these lncRNAs were likely involved in the regulation of many key signaling pathways during bovine oocyte maturation from GV to MII stage, as well as multiple lncRNA-mRNA networks. One novel lncRNA (MSTRG.19140) was particularly interesting, as it appeared to mediate the regulation of oocyte meiotic resumption, progesterone-mediated oocyte maturation, and cell cycle. Therefore, this study enhanced insights into the regulation of molecular mechanisms of bovine oocyte maturation from a lncRNA-mRNA network perspective.