title: Sperm Proteome Maturation in the Mouse Epididymis.
abstract: In mammals, transit through the epididymis, which involves the acquisition, loss and modification of proteins, is required to confer motility and fertilization competency to sperm. The overall dynamics of maturation is poorly understood, and a systems level understanding of the complex maturation process will provide valuable new information about changes occurring during epididymal transport. We report the proteomes of sperm collected from the caput, corpus and cauda segments of the mouse epididymis, identifying 1536, 1720 and 1234 proteins respectively. This study identified 765 proteins that are present in sperm obtained from all three segments. We identified 1766 proteins that are potentially added (732) or removed (1034) from sperm during epididymal transit. Phenotypic analyses of the caput, corpus and cauda sperm proteomes identified 60 proteins that have known sperm phenotypes when mutated, or absent from sperm. Our analysis indicates that as much as one-third of proteins with known sperm phenotypes are added to sperm during epididymal transit. GO analyses revealed that cauda sperm are enriched for specific functions including sperm-egg recognition and motility, consistent with the observation that sperm acquire motility and fertilization competency during transit through the epididymis. In addition, GO analyses revealed that the immunity protein profile of sperm changes during sperm maturation. Finally, we identified components of the 26S proteasome, the immunoproteasome, and a proteasome activator in mature sperm.
authors.affiliation: Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America.
authors.forename: Sheri
authors.initials: S
authors.lastname: Skerget
authors.affiliation: Center for Proteomics, Translational Genomics Research Institute, Phoenix, Arizona, United States of America.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Rosenow
authors.affiliation: Center for Proteomics, Translational Genomics Research Institute, Phoenix, Arizona, United States of America.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Petritis
authors.affiliation: Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Karr
mesh_terms: D000818:Animals; D004822:Epididymis / Q000378:metabolism* / Q000648:ultrastructure; D063990:Gene Ontology; D007109:Immunity / Q000235:genetics; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D051379:Mice; D009687:Nuclear Proteins / Q000032:analysis; D009928:Organ Specificity; D010641:Phenotype; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D020543:Proteome; D013079:Sperm Maturation / Q000502:physiology*; D013094:Spermatozoa / Q000002:abnormalities / Q000276:immunology / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D008565:Membrane Proteins; D009687:Nuclear Proteins; D020543:Proteome; D046988:Proteasome Endopeptidase Complex