title: Analysis of the sperm head protein profiles in fertile men: consistency across time in the levels of expression of heat shock proteins and peroxiredoxins.
abstract: We investigated the identity and quantitative variations of proteins extracted from human sperm heads using a label-free Gel-MS approach. Sperm samples were obtained from three men with high sperm counts at three different time points. This design allowed us to analyse intra-individual and inter-individual variations of the human sperm head proteome. Each time point was analyzed in triplicate to minimize any background artifactual effects of the methodology on the variation analyses. Intra-individual analysis using the spectral counting method revealed that the expression levels of 90% of the common proteins identified in three samples collected at various time-points, separated by several months, had a coefficient of variation of less than 0.5 for each man. Across individuals, the expression level of more than 80% of the proteins had a CV under 0.7. Interestingly, 83 common proteins were found within the core proteome as defined by the intra- and inter-variation analyses set criteria (CV<0.7). Some of these uniformly expressed proteins were chaperones, peroxiredoxins, isomerases, and cytoskeletal proteins. Although there is a significant level of inter-individual variation in the protein profiles of human sperm heads even in a well-defined group of men with high sperm counts, the consistent expression levels of a wide range of proteins points to their essential role during spermatogenesis.
authors.affiliation: Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada.
authors.forename: Elsa
authors.initials: E
authors.lastname: Kichine
authors.forename: Marcos
authors.initials: M
authors.lastname: Di Falco
authors.forename: Barbara F
authors.initials: BF
authors.lastname: Hales
authors.forename: Bernard
authors.initials: B
authors.lastname: Robaire
authors.forename: Peter
authors.initials: P
authors.lastname: Chan
mesh_terms: D000328:Adult; D003598:Cytoskeletal Proteins / Q000235:genetics; D005298:Fertility / Q000235:genetics*; D015870:Gene Expression; D020869:Gene Expression Profiling; D014644:Genetic Variation; D006360:Heat-Shock Proteins / Q000235:genetics*; D006801:Humans; D007535:Isomerases / Q000235:genetics; D008297:Male; D018832:Molecular Chaperones / Q000235:genetics; D054464:Peroxiredoxins / Q000235:genetics*; D020543:Proteome / Q000235:genetics*; D013076:Sperm Count; D013077:Sperm Head / Q000737:chemistry* / Q000378:metabolism; D013091:Spermatogenesis / Q000235:genetics*; D013997:Time Factors
chemical_list: D003598:Cytoskeletal Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D020543:Proteome; D054464:Peroxiredoxins; D007535:Isomerases