title: Proteomic analysis of heparin-binding proteins from human seminal plasma: a step towards identification of molecular markers of male fertility.
abstract: Glycosaminoglycans, especially heparin, are involved in various cell processes such as apoptosis, cell cycle control, platelet activation, capacitation, acrosome reaction and sperm decondensation. Heparin-binding proteins (HBPs) are essential constituents of human seminal fluid, which bind to sperm lipids containing the phosphorylcholine group and mediate the fertilization process. We utilized a proteomic set-up consisting of affinity chromatography, isoelectric focusing (IEF) coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI TOF/MS) for protein analysis of human HBPs. We resolved 70 different spots on two-dimensional (2-D) gel and subsequently identifi ed these proteins. Forty different types of proteins were identified. Functional analysis revealed that 38% of the proteins belonged to the enzyme category, 20% were involved in RNA processing and transcription, 18% in structure and transport function, and 16% in cell recognition and signal transduction. We also identified 8% of proteins with unknown functions, although their expression in seminal fluid has been documented. Proteins of seminal fluid that bind heparin may be directly involved in sperm capacitation and acrosome reaction (AR), which are the two critical steps for fertilization. This information on HBPs would be useful for identifying potential biomarkers of fertility in the near future.
authors.affiliation: Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110 029, India.
authors.forename: Vijay
authors.initials: V
authors.lastname: Kumar
authors.forename: Md Imtaiyaz
authors.initials: MI
authors.lastname: Hassan
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Tomar
authors.forename: Tara
authors.initials: T
authors.lastname: Kashav
authors.forename: Jaya
authors.initials: J
authors.lastname: Nautiyal
authors.forename: Sarman
authors.initials: S
authors.lastname: Singh
authors.forename: Tej P
authors.initials: TP
authors.lastname: Singh
authors.forename: Savita
authors.initials: S
authors.lastname: Yadav
mesh_terms: D020816:Amino Acid Motifs; D023181:Antimicrobial Cationic Peptides / Q000032:analysis* / Q000235:genetics; D015415:Biomarkers / Q000032:analysis*; D001798:Blood Proteins / Q000032:analysis* / Q000235:genetics; D002352:Carrier Proteins / Q000032:analysis* / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D005298:Fertility / Q000502:physiology*; D006493:Heparin / Q000378:metabolism; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D020543:Proteome / Q000032:analysis*; D012661:Semen / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism
chemical_list: C062991:AZU1 protein, human; D023181:Antimicrobial Cationic Peptides; D015415:Biomarkers; D001798:Blood Proteins; D002352:Carrier Proteins; D020543:Proteome; D006493:Heparin