Assessing spermatozoal small ribonucleic acids and their relationship to blastocyst development in idiopathic infertile males

Abstract

Clinical testing strategies for diagnosing male factor infertility are limited. A deeper analysis of spermatozoa-derived factors could potentially diagnose some cases of ‘unexplained infertility’. Spermatozoa carry a rich and dynamic profile of small RNAs, which have demonstrated potential developmental importance and association with fertility status. We used next-generation sequencing to correlate sperm small RNA profiles of normozoospermic males (n = 54) with differing blastocyst development rates, when using young donor oocytes. While ribosomal RNAs accounted for the highest number of sequencing reads, transfer RNA fragments of tRNAGly/GCC and tRNAVal-CAC were the most abundant sequences across all sperm samples. A total of 324 small RNAs were differentially expressed between samples with high (n = 18) and low (n = 14) blastocyst rates (p-adj < 0.05). 93 miRNAs were differentially expressed between these groups (p-adj < 0.05). Differentially expressed transfer RNA fragments included: 5’-tRF-Asp-GTC; 5’-tRF-Phe-GAA; and 3’-tRF-Ser-GCA. Differentially expressed miRNAs included: let-7f-2-5p; miR-4755-3p; and miR-92a-3p. This study provides the foundation on which to validate a clinical panel of fertility-related sperm small RNAs, as well as to pursue potential mechanisms through which they alter blastocyst development

Identification of protein candidates in spermatozoa of water buffalo (Bubalus bubalis) bulls helps in predicting their fertility status

“…It is also hypothesised that mature spermatozoa are not able to synthesize proteins (Rahman et al, 2013). Since sperm is a terminally differentiated cell without transcriptional and translational machinery and because spermatozoa carry pre-synthesized proteins as final products, therefore, proteomics is superior to other "omics" strategies for identifying the fertility biomarkers (Rahman et al, 2013;Sun et al, 2021;Hamilton et al, 2022). Several proteins are known to regulate male fertility by assisting the spermatozoa in maintaining their structure, survival, and fertilizing capability in the female reproductive tract (FRT).…”