title: Rab5b localization to early endosomes in the protozoan human pathogen Leishmania donovani.
abstract: Leishmania donovani is a primitive trypanosomatid pathogen of humans. This protozoan is apically polarized such that the flagellar reservoir, the exclusive site of endocytosis and exocytosis, is situated at the anterior end. Recent evidence for the existence of an endocytic pathway in Leishmania has prompted us to investigate candidate temporal markers for endocytosis. In this study we identify the L. donovani Rab5b gene, and demonstrate the localization of a Rab5b chimera to early endosomes. A full-length Rab5b protein was fused to green fluorescent protein (GFP) to generate a chimeric protein GFP::Rab5b. Transfected L. donovani promastigotes carrying this chimeric construct displayed GFP::Rab5b localization. Additionally, incubation of transfected promastigotes with the fluid-phase marker Texas Red dextran demonstrated anterior co-localization of GFP::Rab5b and dye. This suggests Rab5b may act as a marker for early endosomes in L. donovani.
authors.affiliation: Cell Biology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, Maryland 20892-0425, USA. marottad@mail.med.upenn.edu
authors.forename: Diane E
authors.initials: DE
authors.lastname: Marotta
authors.forename: Noel
authors.initials: N
authors.lastname: Gerald
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Dwyer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003911:Dextrans; D011992:Endosomes / Q000378:metabolism*; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D007893:Leishmania donovani / Q000166:cytology / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids; D021381:Protein Transport; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D014162:Transfection; D014966:Xanthenes; D020696:rab5 GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D003911:Dextrans; D015800:Protozoan Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014966:Xanthenes; D049452:Green Fluorescent Proteins; C034657:Texas red; D020696:rab5 GTP-Binding Proteins