Quantitative evaluation of HILS1 expression and its potential interaction with regulating microRNAs in testicular tissue of infertile men

Background: Spermatogenesis is a highly dynamic process that is controlled by many factors including epigenetic regulators. Spermatid-specific linker histone H1-like protein (Hils1), a highly expressed protein in the nuclei of elongating and elongated spermatids, has been suggested to participate in spermatid nuclear condensation during spermiogenesis in mice. HILS1 gene does not encode any protein in humans, and might serve as a long non-coding RNA to exert its potentially important effects during human spermiogenesis, particularly because it is specifically expressed in testis and spermatozoa.Objective: This study was aimed to evaluate the HILS1 transcript levels in testis and identify microRNAs potentially regulating this gene in testicular tissue of infertile men under testicular epididymal sperm extraction (TESE) operation.Materials and Methods: Twenty-two samples of testicular biopsy from infertile men were obtained using TESE procedure, including five samples from patients with hypospermatogenesis (positive control), seven samples from patients with Sertoli cell only syndrome, and 10 samples from patients with complete maturation arrest at second spermatocyte level. The expression of HILS1 transcript was analyzed using qRT-PCR and GAPDH was used as the internal normalization control. Several microRNA software such as miRBase, RNAfold, miR-DB, and TargetScan were used to predict and investigate the potentiality of HILS1 to be either regulated by microRNAs or processed into microRNAs.Results: We observed that the expression level of HILS1 transcript was significantly decreased in Sertoli cell only syndrome and complete maturation arrest at second spermatocyte in comparison to the positive control. We also found some microRNAs, particularly miR-363, potentially regulating HILS1 transcript at the post-transcriptional level. Moreover, our analyses suggested that HILS1 might be processed into microRNAs homologous to miR-5588 and miR-665.Conclusion: Our collective results suggest that regulation of HILS1 might play an important role in human spermiogenesis, which may have implications for improved treatment of men’s infertility.

کلیدواژه ها:

HILS1 ، Spermiogenesis ، Infertility ، MicroRNA ، Bioinformatics