title: Identification and disruption of a rhoptry-localized homologue of sodium hydrogen exchangers in Toxoplasma gondii.
abstract: Na+/H+ exchangers (NHEs) are ubiquitous membrane proteins that catalyze the exchange of Na+ for H+ and are critical in pH and cell volume regulation, as well as osmotolerance. In this study, we identify and characterize a novel NHE, TgNHE2, in Toxoplasma gondii. Immunofluorescence studies show that TgNHE2 is localized to the rhoptries, secretory organelles involved in invasion. TgNHE2 is the first intracellular NHE to be characterized in a protozoan parasite and its localization suggests possible roles for the rhoptries in osmotolerance and/or as secretory lysosomes-like granules.
authors.affiliation: Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA.
authors.forename: Ariela O
authors.initials: AO
authors.lastname: Karasov
authors.forename: John C
authors.initials: JC
authors.lastname: Boothroyd
authors.forename: Gustavo
authors.initials: G
authors.lastname: Arrizabalaga
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D008565:Membrane Proteins / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D008969:Molecular Sequence Data; D015388:Organelles / Q000737:chemistry*; D015800:Protozoan Proteins / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D017923:Sodium-Hydrogen Exchangers / Q000032:analysis* / Q000502:physiology; D014122:Toxoplasma / Q000737:chemistry*; D014882:Water-Electrolyte Balance / Q000502:physiology
chemical_list: D008565:Membrane Proteins; D015800:Protozoan Proteins; D017923:Sodium-Hydrogen Exchangers