The miRNA expression profiles of round spermatids during GRTH/DDX25 mediated spermiogenesis: mRNA-miRNA Network analysis [mRNAseq]

GRTH/DDX 25 is a member of the DEAD-box family of RNA helicases that play an essential role in spermatogenesis. Regulation of spermatogenesis occurs at the levels of transcription, post-transcriptional and translational levels which needs to be explored in detail. miRNAs regulate the expression of important genes involved in spermatid elongation process. Differential miRNA expression in round spermatids (RS) of GRTH KO and GRTH-KI mice in comparison with mRNAs remains unexplored. Our miRNAseq analysis of small RNAs obtained from RS reveal differential expression of important miRNAs that regulate spermatid differentiation, apoptosis, chromatin compaction and ubiquitination. mRNAseq analysis of RS isolated from GRTH-KI and GRTH-KO mice models were also carried-out to study the putative miRNA targets and mRNA-miRNA interaction. mRNAseq analysis revealed specific set of mRNAs that are critical for sperm chromatin compaction, ubiquitination and spermatid elongation etc. miRNA-mRNA interaction prediction highlighted differentially expressed/enriched miRNA transcripts whose predicted mRNA targets were differentially expressed. Based on the interaction information of the miRNAs-mRNAs differential analysis, the miRNA-mRNA network was constructed. These results demonstrate the importance of miRNA in the translational arrest and stability of germ cell specific mRNAs which are critical for later stages of spermiogenesis and fertility. Overall design: Differential expression analysis of mRNA and miRNA transcriptomic profile in round spermatids. This study compares the miRNA/mRNA profiles of GRTH knock-out and GRTH knock-in round spermatids to wild-type to assess the role of GRTH in spermiogenesis.