Project description:Human TEX101 is a testis-specific cell membrane protein expressed exclusively in male germ cells and a validated biomarker of male infertility. TEX101 was suggested to function as a cell surface chaperone of numerous proteins involved in sperm migration and sperm-egg interaction. However, the precise functional roles of human TEX101 in spermatogenesis and fertilization are unknown. Here, we show that a common homozygous variant rs35033974 of TEX101 (G99V) with ~1% frequency in the general population may be associated with idiopathic male infertility. Spermatozoa from patients with homozygous rs35033974 exhibited near-complete degradation of variant G99V TEX101 protein and concomitant degradation of its interactome, as revealed by proteomic measurements. Substantially reduced levels of numerous testis-specific membrane proteins involved in sperm migration and sperm-oocyte fusion (including LY6K, IZUMO3 and ADAM29) were confirmed in spermatozoa of men with homozygous G99V variant. These men were previously diagnosed with idiopathic male infertility or oligospermia and failed the treatment by intrauterine insemination. Collectively, these data may facilitate diagnostics of idiopathic male infertility, provides a rational for selection of male infertility treatments and validate TEX101 and its interactome as targets to develop non-hormonal male contraceptives.
Project description:The aim of this study was to achieve a higher resolution of the human sperm proteome for better understanding of the molecular causes of male infertility. For this purpose, we examined the proteomic profiles of sperm from 76 men for proteins with deregulated abundances. Infertile men had abnormal semen parameters and were involuntarily childless. Men in the cohort with normal fertility had normozoospermia and had fathered children without medical assistance. Mass spectrometry analysis led to an in-depth reconstruction of the human sperm proteome. The corresponding genes were mainly involved in cellular motility, response to stimuli, adhesion, and reproduction. We also observed increasing numbers of at least three-fold differentially abundant sperm proteins from oligozoospermia and oligoasthenozoospermia to oligoasthenoteratozoospermia, compared with normozoospermia. Primarily, flagellar assembly and sperm motility, sperm-egg interaction, and male gametogenesis were affected. This suggests that sperm of infertile men carry signatures of impaired sperm production and are functionally impaired. Not least, we present new male infertility markers in addition to established ones.
Project description:Infertility is a widespread problem, affecting around 15% of couples worldwide, and is defined as the inability to achieve pregnancy within one year despite unprotected intercourse 1. Infertility can be caused by either male or female reproductive issues. Various medical conditions including malignancies, infections, urogenital conditions, or genetic causes can contribute to male infertility. However, 30-40% of men in their reproductive age are affected by idiopathic infertility, according to the guidelines of European Association of Urology (EAU) 1. Towards a better understanding of male infertility, it is mandatory to achieve a comprehensive understanding of involved genes, their RNA transcripts, and regulatory factors, including miRNAs, which influence the expression level of proteins. Therefore, such proteins need to be identified to investigate their role in spermatogenesis and male infertility. Although there are numerous studies on RNAs, including miRNAs related to male infertility 2-9, there are few studies aiming to cover the whole proteome of human sperm 10. The sperm transcriptome comprises a total of 60,505 transcripts including 11,688 differentially expressed transcripts in infertile and fertile men, as reported by Joshi et al. (2022)11. The entire sperm proteome encompasses 6871 proteins, as summarized by Castillo et al. (2018)10. Nevertheless, there is still a lack of high-throughput studies aiming to identify dysregulated proteins in sperm from subfertile men. Only few studies focused on comparisons of the sperm proteome in men with asthenozoospermia and there is virtually no proteomic studies of oligoasthenozoospermic men 12. Some identified proteins in sperm have functions in maintaining sperm motility and enabling fertilization and are involved in structural composition and/or energy metabolism 12-14 and others are not yet functionally characterized. In this study, we employed Mass spectrometry (MS) technology that is still rarely used in the field of human reproductive research to investigate the proteomic landscape of human sperm and their differential expression patterns in men with subfertility.
Project description:We examine how NGS sequencing of sperm can provide a window as to how particular perturbations of the sperm RNA profile from baseline may be indicative of male factor infertility, and may thus provide direction as to proper course of infertility treatment for couple. NGS RNA-seq of 72 sperm samples from male partner of couples undergoing fertility treatment
Project description:Male factor infertility is increasing and recognized as playing a key role in reproductive health and disease. The current primary diagnostic approach is to assess sperm quality associated with reduced sperm number and motility, which has been historically of limited success in separating fertile from infertile males. The current study was designed to develop a molecular analysis to identify male infertility using genome wide alterations in sperm DNA methylation. A signature of differential DNA methylation regions (DMRs) was identified to be associated with male infertility patients. A promising therapeutic treatment of male infertility is the use of follicle stimulating hormone (FSH) analogs which improved sperm numbers and motility in a sub-population of infertility patients. The current study also identified genome-wide DMRs that were associated with the patients that were responsive to FSH therapy versus those that were non-responsive.
Project description:We found that differentially expressed (DE) miRNAs were mainly enriched in pathways involved in cell apoptosis, including mTOR and p53 signaling pathways. Furthermore, gain- and loss-of-function analyses and dual luciferase assays demonstrated that endogenous miR-26a-5p and let-7g-5p have potential anti-apoptotic and pro-survival functions in sperm cells through targeting PTEN and PMAIP1 genes. Further comparisons revealed high similarities in miRNA profiles between seminal plasma exosomes and sperm cells, both in HC and CT groups. Our study revealed that miRNAs in sperm cells and seminal plasma exosomes have important functions in male reproduction, suggesting they could be used as potential treatment targets or novel diagnostic markers for male infertility.
Project description:Human TEX101 is a testis-specific cell membrane protein expressed exclusively in male germ cells and a validated biomarker of male infertility. TEX101 was suggested to function as a cell surface chaperone of numerous proteins involved in sperm migration and sperm-egg interaction. However, the precise functional roles of human TEX101 in spermatogenesis and fertilization are unknown. Here, we show that a common homozygous variant rs35033974 of TEX101 (G99V) with ~1% frequency in the general population may be associated with idiopathic male infertility. Spermatozoa from patients with homozygous rs35033974 exhibited near-complete degradation of variant G99V TEX101 protein and concomitant degradation of its interactome, as revealed by proteomic measurements. Substantially reduced levels of numerous testis-specific membrane proteins involved in sperm migration and sperm-oocyte fusion (including LY6K, IZUMO3 and ADAM29) were confirmed in spermatozoa of men with homozygous G99V variant. These men were previously diagnosed with idiopathic male infertility or oligospermia and failed the treatment by intrauterine insemination. Collectively, these data may facilitate diagnostics of idiopathic male infertility, provides a rational for selection of male infertility treatments and validate TEX101 and its interactome as targets to develop non-hormonal male contraceptives.
Project description:Current approaches to diagnosing male infertility inadequately assess the complexity of the male gamete. Beyond the paternal haploid genome, spermatozoa also deliver coding and non-coding RNAs to the oocyte. While sperm-borne RNAs have demonstrated potential involvement in embryo development, the underlying mechanisms remain unclear. In this study, 47 sperm samples from normozoospermic males undergoing fertility treatment using donor oocytes were sequenced and analyzed to evaluate associations between sperm RNA elements (exon-sized sequences) and blastocyst progression. A total of 366 RNA elements (REs) were significantly associated with blastocyst rate (padj<0.05), some of which were linked to genes related to critical developmental processes, including mitotic spindle formation and both ectoderm and mesoderm specification. Of note, 27 RE-associated RNAs are predicted targets of our previously reported list of developmentally significant miRNAs. Inverse RE-miRNA expression patterns were consistent with miRNA-mediated down-regulation. This study provides a comprehensive set of REs which differ by the patient’s ability to produce blastocysts. This knowledge can be leveraged to improve clinical screening of male infertility and ultimately reduce time to pregnancy.