Functional evaluation of LTR-derived lncRNAs in porcine oocytes and zygotes with RNA-seq and small RNA-seq

Abstract

Long noncoding RNAs (lncRNAs) are increasingly being recognized as modulators of early embryonic development in mammals. However, they are seldom investigated in pigs. Here, to annotate full-length RNA transcripts, we performed annotation using a newly developed computational pipeline—an RNA-seq and small RNA-seq combined strategy—using our previously obtained RNA-seq and small RNA-seq data from porcine oocytes and zygotes. As evidenced by the length comparison, the frequency of the core promoter, and the polyadenylation signal motifs, the transcripts appear to be full-length. Furthermore, our strategy allowed the identification of a large number of endogenous retrovirus-associated lncRNAs (ERV-lncRNAs) and found that some of them were highly expressed in porcine zygotes, as compared to oocytes. Through the knockdown strategy, two ERV-lncRNAs (TCONS_00035465 and TCONS_00031520) were identified as playing potential roles in the early embryo development of pigs, laying a foundation for future research.