Dataset Information

Proteomic Analysis Reveals that Topoisomerase 2A is Associated with Defective Sperm Head Morphology.

ABSTRACT: Male infertility is widespread and estimated to affect 1 in 20 men. Although in some cases the etiology of the condition is well understood, for at least 50% of men, the underlying cause is yet to be classified. Male infertility, or subfertility, is often diagnosed by looking at total sperm produced, motility of the cells and overall morphology. Although counting spermatozoa and their associated motility is routine, morphology assessment is highly subjective, mainly because of the procedure being based on microscopic examination. A failure to diagnose male-infertility or sub-fertility has led to a situation where assisted conception is often used unnecessarily. As such, biomarkers of male infertility are needed to help establish a more consistent diagnosis. In the present study, we compared nuclear extracts from both high- and low-quality spermatozoa by LC-MS/MS based proteomic analysis. Our data shows that nuclear retention of specific proteins is a common facet among low-quality sperm cells. We demonstrate that the presence of Topoisomerase 2A in the sperm head is highly correlated to poor head morphology. Topoisomerase 2A is therefore a potential new biomarker for confirming male infertility in clinical practice.

SUBMITTER: Netherton J

PROVIDER: S-EPMC7050105 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Proteomic Analysis Reveals that Topoisomerase 2A is Associated with Defective Sperm Head Morphology.

Netherton Jacob J Ogle Rachel A RA Hetherington Louise L Silva Balbin Villaverde Ana Izabel AI Hondermarck Hubert H Baker Mark A MA

Molecular & cellular proteomics : MCP 20191217 3

Male infertility is widespread and estimated to affect 1 in 20 men. Although in some cases the etiology of the condition is well understood, for at least 50% of men, the underlying cause is yet to be classified. Male infertility, or subfertility, is often diagnosed by looking at total sperm produced, motility of the cells and overall morphology. Although counting spermatozoa and their associated motility is routine, morphology assessment is highly subjective, mainly because of the procedure bein ...[more]

PMID: 31848259

Similar Datasets

Project description:BackgroundSperm morphology mainly refers to the shape of the head, the length of the flagellar segments, including the midpiece, principal piece and end piece, and the size of the accessory structures, including axonemes, outer dense fibers (ODFs), mitochondrial sheath (MS) and fibrous sheath (FS). Across species, there is considerable diversity in morphology. An established theory posits that the length of the sperm flagellum, especially the length of the midpiece, is a critical factor influencing sperm metabolism and velocity. However, our understanding of the relationships between sperm ultrastructures and the sperm flagellar length is incomplete.MethodsThe morphologies of sperm from 10 mammalian species, human, mouse, rat, dog, rabbit, goat, pig, bull, guinea pig and golden hamster, were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). According to the SEM and TME images, the length of sperm heads and flagellar segments, the cross-sectional areas of the accessory structures and flagella and the width of sperm heads were measured using Image J software. The variation tendencies (referred to as slope) of the accessory structures along flagella were calculated by the linear regression method. Mitochondrial functions were measured using commercial kits. The velocities of sperm were measured using CASA software.ResultsThe three-dimensional morphologies of sperm from 10 species and the slopes of internal accessory structures along flagella were obtained. The width of the axoneme tapered slightly from the base to the tip of the sperm flagellum, and slopes of the axonemes correlated negatively with the variability in flagellar length across species. Additionally, the cross-sectional areas of the ODFs and/or the MS were positively correlated with the lengths of the midpiece, principal piece, and total flagellum, as well as with sperm velocities. Mitochondrial volumes were positively correlated with ATP content and sperm swimming velocities.ConclusionsOur results not only show the relationship between sperm internal structures, flagellar length and sperm physiology but also provide sizes of mitochondria and ODFs as new targets with which to study the regulation of sperm length and velocity.

Project description:BackgroundActin-like 7 A (ACTL7A) is essential for acrosome formation, fertilization and early embryo development. ACTL7A variants cause acrosome detachment responsible for male infertility and early embryonic arrest. In this study, we aim to explore the additional functions of ACTL7A beyond the process of acrosome biogenesis and investigate the possible underlying mechanisms.MethodsNuclear morphology analysis was used to observe the sperm head shape of ACTL7A-mutated patients. Actl7a knock-out (KO) mouse model was generated. Immunofluorescence and transmission electron microscopy (TEM) were performed to analyze the structure of spermatids during spermiogenesis. Tandem mass tags labeling quantitative proteomics strategy was employed to explore the underlying molecular mechanisms. The expression levels of key proteins in the pathway were analyzed by western blotting. Intracytoplasmic sperm injection (ICSI)-artificial oocyte activation (AOA) technology was utilized to overcome fertilization failure in male mice with a complete knockout of Actl7a.ResultsThe new phenotype of small head sperm associated with loss of ACTL7A in patients was discovered, and further confirmed in Actl7a-KO mice. Immunofluorescence and TEM analyses revealed that the deletion of ACTL7A damaged the formation of acrosome-acroplaxome-manchette complex, leading to abnormalities in the shaping of sperm heads. Moreover, a proteomic analysis of testes from WT and Actl7a-KO mice revealed that differentially expressed genes were notably enriched in PI3K/AKT/mTOR signaling pathway which is strongly associated with autophagy. Inhibition of autophagy via PI3K/AKT/mTOR signaling pathway activation leading to PDLIM1 accumulation might elucidate the hindered development of manchette in Actl7a-KO mice. Remarkably, AOA successfully overcame fertilization failure and allowed for the successful production of healthy offspring from the Actl7a complete knockout male mice.ConclusionsLoss of ACTL7A causes small head sperm as a result of defective acrosome-acroplaxome-manchette complex via autophagy inhibition. ICSI-AOA is an effective technique to rescue male infertility resulting from ACTL7A deletion. These findings provide essential evidence for the diagnosis and treatment of patients suffering from infertility.

Dataset Information

Proteomic Analysis Reveals that Topoisomerase 2A is Associated with Defective Sperm Head Morphology.

Publications

Proteomic Analysis Reveals that Topoisomerase 2A is Associated with Defective Sperm Head Morphology.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets