title: Identification of a Novel Microtubule-Binding Protein in Giardia lamblia.
abstract: Giardia lamblia is a protozoan that causes diarrheal diseases in humans. Cytoskeletal structures of Giardia trophozoites must be finely reorganized during cell division. To identify Giardia proteins which interact with microtubules (MTs), Giardia lysates were incubated with in vitro-polymerized MTs and then precipitated by ultracentifugation. A hypothetical protein (GL50803_8405) was identified in the precipitated fraction with polymerized MTs and was named GlMBP1 (G. lamblia microtubule-binding protein 1). Interaction of GlMBP1 with MTs was confirmed by MT binding assays using recombinant GlMBP1 (rGlMBP1). In vivo expression of GlMBP1 was shown by a real-time PCR and western blot analysis using anti-rGlMBP1 antibodies. Transgenic G. lamblia trophozoites were constructed by integrating a chimeric gene encoding hemagglutinin (HA)-tagged GlMBP1 into a Giardia chromosome. Immunofluorescence assays of this transgenic G. lamblia, using anti-HA antibodies, revealed that GlMBP1 mainly localized at the basal bodies, axonemes, and median bodies of G. lamblia trophozoites. This result indicates that GlMBP1 is a component of the G. lamblia cytoskeleton.
authors.affiliation: Department of Environmental Medical Biology and Institute of Tropical Medicine, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea.
authors.forename: Juri
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Environmental Medical Biology and Institute of Tropical Medicine, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea.
authors.forename: Soon-Jung
authors.initials: SJ
authors.lastname: Park
mesh_terms: D015153:Blotting, Western; D002352:Carrier Proteins / Q000032:analysis* / Q000235:genetics; D003001:Cloning, Molecular; D015870:Gene Expression; D020869:Gene Expression Profiling; D016829:Giardia lamblia / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000378:metabolism*; D015388:Organelles / Q000737:chemistry; D011485:Protein Binding; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014461:Ultracentrifugation
chemical_list: D002352:Carrier Proteins; D011994:Recombinant Proteins
keywords: Giardia lamblia; microtubule-binding protein 1