Proteomic Profiling of Mouse Epididymosomes Reveals their Contributions to Post-testicular Sperm Maturation.
Mol Cell Proteomics
; 18(Suppl 1): S91-S108, 2019 03 15.
Article
em En
| MEDLINE
| ID: mdl-30213844
ABSTRACT
The functional maturation of spermatozoa that is necessary to achieve fertilization occurs as these cells transit through the epididymis, a highly specialized region of the male reproductive tract. A defining feature of this maturation process is that it occurs in the complete absence of nuclear gene transcription or de novo, protein translation in the spermatozoa. Rather, it is driven by sequential interactions between spermatozoa and the complex external milieu in which they are bathed within lumen of the epididymal tubule. A feature of this dynamic microenvironment are epididymosomes, small membrane encapsulated vesicles that are secreted from the epididymal soma. Herein, we report comparative proteomic profiling of epididymosomes isolated from different segments of the mouse epididymis using multiplexed tandem mass tag (TMT) based quantification coupled with high resolution LC-MS/MS. A total of 1640 epididymosome proteins were identified and quantified via this proteomic method. Notably, this analysis revealed pronounced segment-to-segment variation in the encapsulated epididymosome proteome. Thus, 146 proteins were identified as being differentially accumulated between caput and corpus epididymosomes, and a further 344 were differentially accumulated between corpus and cauda epididymosomes (i.e., fold change of ≤ -1.5 or ≥ 1.5; p, < 0.05). Application of gene ontology annotation revealed a substantial portion of the epididymosome proteins mapped to the cellular component of extracellular exosome and to the biological processes of transport, oxidation-reduction, and metabolism. Additional annotation of the subset of epididymosome proteins that have not previously been identified in exosomes revealed enrichment of categories associated with the acquisition of sperm function (e.g., fertilization and binding to the zona pellucida). In tandem with our demonstration that epididymosomes are able to convey protein cargo to the head of maturing spermatozoa, these data emphasize the fundamental importance of epididymosomes as key elements of the epididymal microenvironment responsible for coordinating post-testicular sperm maturation.
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Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Maturação do Esperma
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Testículo
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Proteômica
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Epididimo
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Vesículas Extracelulares
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Mol Cell Proteomics
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Austrália