title: Nocodazole inhibits macronuclear infection with Holospora obtusa in Paramecium caudatum.
abstract: Holospora obtusa is a Gram-negative bacterium inhabiting the macronucleus of the ciliate Paramecium caudatum. Experimental infection with H. obtusa was carried out under nocodazole treatment. Nocodazole has been shown to cause disassembly of the cytoplasmic microtubules radiating from the cytopharynx and postoral fibers in P. caudatum. Treatment with this drug did not prevent the ingestion of both prey bacteria and H. obtusa, but it reduced the phagosome number and affected cyclosis. In situ hybridization revealed infectious forms of this endobiont very close to the macronucleus, but never inside it. These results indicate that disassembly of microtubules does not impair transportation of the infectious forms of H. obtusa in the cytoplasm, but that it completely blocks the invasion of the nucleus by the bacteria.
authors.affiliation: Department of Cytology and Histology, Saint Petersburg State University, Universitetskaya naberezhnaya 7/9, 199034 Saint Petersburg, Russia. saban@mail333.com
authors.forename: E V
authors.initials: EV
authors.lastname: Sabaneyeva
authors.forename: S I
authors.initials: SI
authors.lastname: Fokin
authors.forename: E V
authors.initials: EV
authors.lastname: Gavrilova
authors.forename: E S
authors.initials: ES
authors.lastname: Kornilova
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000382:microbiology; D000818:Animals; D003595:Cytoplasmic Streaming / Q000187:drug effects; D042281:Holosporaceae / Q000187:drug effects* / Q000302:isolation & purification; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D048648:Macronucleus / Q000382:microbiology* / Q000648:ultrastructure; D008870:Microtubules / Q000187:drug effects / Q000382:microbiology; D015739:Nocodazole / Q000494:pharmacology*; D048488:Paramecium caudatum / Q000382:microbiology* / Q000648:ultrastructure; D010587:Phagocytosis / Q000187:drug effects; D010588:Phagosomes / Q000187:drug effects
chemical_list: D015739:Nocodazole