title: Subpellicular and flagellar microtubules of Trypanosoma brucei brucei contain the same alpha-tubulin isoforms.
abstract: The cytoskeleton of the parasitic hemoflagellate Trypanosoma brucei brucei essentially consists of two microtubule-based structures: a subpellicular layer of singlet microtubules, which are in close contact with the cell membrane, and the flagellar axoneme. In addition, the cells contain a small pool of soluble tubulin. Two-dimensional gel electrophoretic analysis of the tubulins present in these subcellular compartments revealed two distinct electrophoretic isoforms of alpha-tubulin, termed alpha 1 and alpha 3. alpha 1-Tubulin most likely represents the primary translation product, while alpha 3-tubulin is a posttranslationally acetylated derivative of alpha 1-tubulin. In the pool of soluble cytoplasmic tubulin, alpha 1 is the predominant species, while the very stable flagellar microtubules contain almost exclusively the alpha 3-tubulin isoform. The subpellicular microtubules contain both isoforms. Neither of the two alpha-tubulin isoforms is organelle specific, but the alpha 3 isoform is predominantly located in stable microtubules.
mesh_terms: D000085:Acetates / Q000378:metabolism; D000107:Acetylation; D000818:Animals; D002458:Cell Fractionation; D004591:Electrophoresis, Polyacrylamide Gel; D005407:Flagella / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008870:Microtubules / Q000648:ultrastructure*; D014176:Protein Biosynthesis; D014346:Trypanosoma brucei brucei / Q000648:ultrastructure*; D014404:Tubulin / Q000032:analysis* / Q000235:genetics / Q000378:metabolism
chemical_list: D000085:Acetates; D014404:Tubulin