P-44: Investigation The Role of MicroR-NAs in Spermatogenesis and Male Infertility

Background: One of the most remarkable processes during spermatogenesis is the drastic change in gene expression. It has been recently proposed that small RNAs such as micorRNAs (miRNAs) contribute a great deal of function in regulation of the gene expression in sperm. Alterations in miRNAs function prove to be detrimental to proper spermatogenesis. As many patients suffer from idiopathic infertility, understanding the effect of miRNAs on molecular pathways would identify possible causes of certain types of infertility. Materials and Methods: In mature sperm, about twothirds of mRNA is partially stored in ribonucleoproteins in chromatoid bodies which are thought to be reservoirs for small RNAs . As investigated , miR-218 is involved in the promotion of apoptosis while miR-34b, miR-34c, miR-449 deficiency implicates as arrest in spermatogenesis at the stage of elongation with no fully formed sperm observed. miR-122 deficiency results in histone replacement complications and leads to loose DNA packaging and increased apoptosis and reduced sperm production. It was observed that miR-888 maintains sperm flagella and mature sperm morphology. miR-19a, miR-19b, miR-372, miR-373 are involved in tumor suppression, lack of which could result in tumor formation. Lastly, a lack of miR-890 would result in improper development of the lumen. Results: A number of miRNAs involved in spermatogenesis have been exposed. Recently, the number of studies exploring the transcripts in sperm has increased, and as a result the number of miRNAs identified is likely to increase soon. Conclusion: Exploring the role of miRNAs in pathways interfering in spermatogenesis not only help understand the function of these small molecules, but also help understand alterations that could cause male infertility. Many of the specific functions of miRNAs are not yet known, but the genes and proteins that they interact with are a window through which their involvement can be understood.