title: Analysis of stage-specific expression of basic proteins in Leishmania infantum.
abstract: Prior analyses of the proteome of the protozoan parasite Leishmania have underrepresented basic proteins. Here, we applied protein fractionation by isoelectric point (pI) using free-flow electrophoresis (FFE) to study stage-specific expression of basic proteins in this pathogen. Overall, we resolved 2469 protein spots in both the flagellated promastigote and the nonmotile amastigote forms in the basic range by two-dimensional gel electrophoresis (2-DE). Highly basic proteins were enriched by FFE fractionation, allowing many to be identified and characterized for the first time by proteomics analysis. Among proteins upregulated in the promastigote stage, we found glycolytic enzymes and flagellar proteins. Proteins upregulated in the amastigote stage included enzymes involved in gluconeogenesis and fatty acid beta-oxidation. In both life stages, many proteins were found in multiple spots or as proteolytic fragments, suggesting that extensive post-translational modification and processing occur. Interestingly, evidence was obtained suggesting that some of these processes may be stage-specific.
authors.affiliation: Centre de Recherche en Infectiologie du Centre de Recherche du CHUL and Département de Microbiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Canada.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Brotherton
authors.forename: Gina
authors.initials: G
authors.lastname: Racine
authors.forename: Aude L
authors.initials: AL
authors.lastname: Foucher
authors.forename: Jolyne
authors.initials: J
authors.lastname: Drummelsmith
authors.forename: Barbara
authors.initials: B
authors.lastname: Papadopoulou
authors.forename: Marc
authors.initials: M
authors.lastname: Ouellette
mesh_terms: D000818:Animals; D015153:Blotting, Western; D005591:Chemical Fractionation; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005456:Fluorescent Dyes; D005786:Gene Expression Regulation / Q000502:physiology*; D007091:Image Processing, Computer-Assisted; D018314:Leishmania infantum / Q000235:genetics / Q000378:metabolism*; D008018:Life Cycle Stages / Q000502:physiology*; D009942:Organometallic Compounds; D040901:Proteomics / Q000379:methods*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D015800:Protozoan Proteins; C515601:Sypro Ruby