摘要
Dysfunctional sperm maturation is the primary reason for the poor sperm motility and morphology in infertile men.Spermatozoa from infertile men were fractioned on three-layer density gradient(80%,60%,and 40%).Fraction 1(Fl)refers to the least mature stage having the lowest den sity,whereas the fraction 4(F4)in eludes the most dense and morphologically mature motile spermatozoa.Fraction 2(F2)and fraction 3(F3)represent the intermediate stages.Proteins were extracted and separated by dimensional gel.Bands were digested with trypsin and analyzed on a LTQ-Orbitrap Elite hybrid mass spectrometer system.Functional annotations of proteins were obtained using bioinformatics tools and pathway databases.A total of 1585 proteins were detected in the four fractions of spermatozoa.A dysregulated protein turnover and protein folding may lead to accumulation of defective proteins or proteins that otherwise would have been eliminated during the process of maturation,resulting in the impairment of sperm fun ction.Aberra nt chaper one expressi on may be a major con tributing factor to the defective sperm function.Androge n receptor was predicted as a transcription regulator in one of the networks and the affected pathways were chaperone-mediated stress response,proteosomal pathway,and sperm function.The down regulation of key pathways and protei ns which compromises the fertilizi ng potential of spermatozoa may provide in sight into the mecha nisms that lead to male infertility.
