title: Differential distribution of alpha-tubulin isotypes in Euplotes eurystomus determined by confocal immunofluorescence microscopy.
abstract: Detergent permeabilized Euplotes eurystomus (a fresh water hypotrichous ciliate) was reacted with monoclonal and polyclonal antibodies specific for either detyrosinated or tyrosinated alpha-tubulin (Glu- or Tyr-tubulin). The isolated cytoskeleton-nuclear complex was examined by Western immunoblotting and by immunofluorescent and electron microscopic methods. Both Glu- and Tyr-tubulins were detected by immunoblot analysis. Immunofluorescent microscopy indicated that the alpha-tubulin isotypes are concentrated in different regions of permeabilized cells: Glu-tubulin is located primarily in cirri, membranelles, and surrounding the macro- and micronuclei. Tyr-tubulin is principally at the bases of cirri and membranelles. This differential distribution of alpha-tubulin isotypes is discussed in terms of current concepts concerning the correlation of tubulin post-translational modifications to microtubule stability. Confocal immunofluorescent imaging was of critical importance in clearly differentiating the Glu-tubulin isotype surrounding the macro- and micronuclei from a brilliantly fluorescent environment originating from cytoskeletal structures. In conjunction with conventional and stereo-electron microscopy, confocal optical microscopy provided convincing evidence for a "basket" of microtubules surrounding both nuclei.
authors.affiliation: University of Tennessee, Oak Ridge Graduate School of Biomedical Sciences 37831-8077.
authors.forename: D E
authors.initials: DE
authors.lastname: Olins
authors.forename: A L
authors.initials: AL
authors.lastname: Olins
authors.forename: M
authors.initials: M
authors.lastname: Robert-Nicoud
authors.forename: T M
authors.initials: TM
authors.lastname: Jovin
authors.forename: J
authors.initials: J
authors.lastname: Wehland
authors.forename: K
authors.initials: K
authors.lastname: Weber
mesh_terms: D000818:Animals; D002463:Cell Membrane Permeability; D002467:Cell Nucleus / Q000648:ultrastructure; D016798:Ciliophora / Q000032:analysis* / Q000648:ultrastructure; D003599:Cytoskeleton / Q000032:analysis / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D048631:Micronucleus, Germline / Q000648:ultrastructure; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000648:ultrastructure; D014404:Tubulin / Q000032:analysis*
chemical_list: D014404:Tubulin