title: Identification and Partial Characterization of Two Populations of Prostasomes by a Combination of Dynamic Light Scattering and Proteomic Analysis.
abstract: Prostasomes are vesicles secreted by prostate epithelial cells and are found in abundance in the semen. Here we characterized two different prostasome populations isolated from human seminal fluid. Prostasomes were isolated using differential centrifugation, while dynamic light scattering (DLS) was used to characterize their size and size distribution. Their protein content was analyzed using two-dimensional electrophoresis and mass spectrometry. DLS showed two distinct prostasome subpopulations in centrifuged seminal plasma, with an average hydrodynamic radius of 80 and 300 nm. The larger population was isolated after centrifugation at 20,000 × g (P20), while the smaller one was recovered at 100,000 × g (P100). The two fractions had a similar lipid composition, showing an elevated content of sphingomyelin and cholesterol. The P100 vesicles showed a significant over-expression of proteins involved in the endosomal sorting complexes required for transport (ESCRT) machinery such as Alix, TSG101, and syntenin-1. Some proteins possibly involved in prostate cancer were present only in one specific population (TMPRSS2 in P100 and VCP in P20). The different size and protein profile in the two subpopulations of prostasomes might support differential roles of the semen vesicles toward the target cells, and/or different secretion pathways from the organ of origin.
authors.affiliation: Sezione di Neurologia, Dipartimento di Medicina, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Chiasserini
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Unità di Ricerca di Biochimica e Biologia Molecolare, Via del Giochetto, 06125, Perugia, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Mazzoni
authors.affiliation: Dipartimento di Fisica and CNR-IPCF, Sapienza Università di Roma, piazzale A. Moro, 2, 00185, Rome, Italy.|Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Viale Regina Elena, 291, 00161, Rome, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Bordi
authors.affiliation: ISC-CNR, UOS Sapienza, P.le Aldo Moro 2, 00185, Rome, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Sennato
authors.affiliation: Sez di Fisiologia e Biochimica, Dipartimento di Medicina Sperimentale, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Susta
authors.affiliation: Sez di Fisiologia e Biochimica, Dipartimento di Medicina Sperimentale, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Orvietani
authors.affiliation: Sez di Fisiologia e Biochimica, Dipartimento di Medicina Sperimentale, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Binaglia
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Unità di Ricerca di Biochimica e Biologia Molecolare, Via del Giochetto, 06125, Perugia, Italy. carlo.palmerini@unipg.it.
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Palmerini
mesh_terms: D000328:Adult; D000626:Aminopeptidases / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D019295:Computational Biology / Q000379:methods; D000067493:Dynamic Light Scattering; D004847:Epithelial Cells / Q000378:metabolism*; D006801:Humans; D008055:Lipids; D008297:Male; D010743:Phospholipids / Q000378:metabolism; D011467:Prostate / Q000378:metabolism*; D020543:Proteome; D040901:Proteomics / Q000379:methods; D012661:Semen / Q000378:metabolism; D055815:Young Adult
chemical_list: D008055:Lipids; D010743:Phospholipids; D020543:Proteome; D002784:Cholesterol; D000626:Aminopeptidases
keywords: Dynamic light scattering; Exosomes; Prostasome; Proteomics; Seminal vesicle