title: Purification and characterization of a native zinc-binding high molecular weight multiprotein complex from human seminal plasma.
abstract: The seminal plasma comprises secretions from various accessory sex glands. During fertilization spermatozoa undergo complex sequences of precisely timed events that are regulated by the activation of different intracellular signaling pathways. The precision and efficacy of these pathways are often influenced by the assembly and interactions of multiprotein complexes, thereby directing the flow of regulatory information. Our knowledge about these protein complexes present in human seminal plasma (HuSP) is limited. Here we report the identification and characterization of a native high molecular weight zinc-binding multiprotein complex from HuSP by utilizing 2-DE followed by MS. Twenty-six proteins representing isoforms and/or fragments of 11 different proteins were found to be assembled in this complex. Prostate-specific antigen, zinc α2-glycoprotein, prostatic acid phosphatase, and prolactin inducible protein were the major proteins of this complex. Dynamic light scattering experiments revealed changes in aggregation pattern accompanied with deviation from physiological pH and in presence of SDS. However, no significant changes were observed in the presence of physiological ligands such as zinc and fructose. The present study will be useful and contribute to guide the future studies performed for elucidation of biological significance of this native complex in HuSP.
authors.affiliation: Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Vikash Kumar
authors.initials: VK
authors.lastname: Yadav
authors.forename: Vijay
authors.initials: V
authors.lastname: Kumar
authors.forename: Nirmal
authors.initials: N
authors.lastname: Chhikara
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kumar
authors.forename: Pallavi
authors.initials: P
authors.lastname: Manral
authors.forename: Tara
authors.initials: T
authors.lastname: Kashav
authors.forename: Savita
authors.initials: S
authors.lastname: Saini
authors.forename: A
authors.initials: A
authors.lastname: Srinivasan
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: D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008970:Molecular Weight; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000302:isolation & purification*; D010449:Peptide Mapping; D012661:Semen / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D046912:Multiprotein Complexes; D015032:Zinc