[Identification of proteins in the seminal plasma of healthy fertile men by shotgun proteomic strategy].
OBJECTIVE
To identify proteins in the seminal plasma of healthy fertile men.


METHODS
Three seminal plasma samples were collected from healthy fertile volunteers by Percoll isolation, and then the balanced mixture of the seminal plasma was separated by SDS-PAGE. The proteins in the gel band underwent enzymoloysis, and was extracted and identified by shotgun proteomic strategy.


RESULTS
A total of 331 proteins were identified, with the molecular weight (MW) ranging from 8 000 to 572 068 and the isoelectric point (pI) from 4.36 to 11.05. Based on the molecular function and biological process of the proteins, 51 (15.4%) were classified as transport proteins, 11 (3.32%) as cell movement proteins, 63 (19.03%) as signal transduction proteins, 147 (44.4%) as proteases, 38 (11.5%) as enzyme regulator proteins, 21 (6.3%) as programmed cell death proteins, 12 (3.62%) as structural proteins and 59 (17.8%) as proteins with unknown molecular function.


CONCLUSIONS
Shotgun proteomic strategy is a good method for protein identification. Annexin A, Annexin-associated proteins and the Ras-related protein Rab were the major members of the signal transducer proteins identified. Ca2+ and G protein signal pathways may play a most important role in the extracellular signal transduction into cells, but the interactions between these proteins remain unknown. The great quantity of enzymes and enzyme regulator proteins identified in the seminal plasma may be closely related with the maintenance of sperm motility and metabolism.
Bai
Jie
J
Clinical Laboratory, General Hospital of PLA, Beijing 100853, China. jiebai69@tom.com
Fu
Shu-Hong
SH
Cai
Li-Li
LL
Sun
Ling
L
Cong
Yu-Long
YL
D000328:Adult; D005298:Fertility; D006801:Humans; D008297:Male; D040901:Proteomics / Q000379:methods*; D012661:Semen / Q000737:chemistry*; D029589:Seminal Plasma Proteins / Q000302:isolation & purification*; D013081:Sperm Motility
D029589:Seminal Plasma Proteins