title: Toxoplasma gondii: further studies on the subpellicular network.
abstract: The association of the pellicle with cytoskeletal elements in Toxoplasma gondii allows this parasite to maintain its mechanical integrity and makes possible its gliding motility and cell invasion. The inner membrane complex (IMC) resembles the flattened membrane sacs observed in free-living protozoa and these sacs have been found to associate with cytoskeletal proteins such as articulins. We used immunofluorescence microscopy to characterise the presence and distribution of plateins, a sub-family of articulins, in T. gondii tachyzoites. A dispersed labelling of the whole protozoan body was observed. Electron microscopy of detergent-extracted cells revealed the presence of a network of 10 nm filaments distributed throughout the parasite. These filaments were labelled with anti-platein antibodies. Screening the sequenced T. gondii genome, we obtained the sequence of an IMC predicted protein with 25% identity and 42% similarity to the platein isoform alpha 1 present in Euplotes aediculatus, but with 42% identity and 55% similarity to that found in Euglena gracilis, suggesting strong resemblance to articulins.
authors.affiliation: Laboratório de Ultraestrutura Celular Hertha Meyer, Centro de Ciências da Saúde, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Leandro
authors.initials: L
authors.lastname: Lemgruber
authors.forename: John A
authors.initials: JA
authors.lastname: Kloetzel
authors.forename: Wanderley de
authors.initials: Wd
authors.lastname: Souza
authors.forename: Rossiane C
authors.initials: RC
authors.lastname: Vommaro
mesh_terms: D001483:Base Sequence; D003598:Cytoskeletal Proteins / Q000737:chemistry / Q000235:genetics; D003599:Cytoskeleton / Q000737:chemistry / Q000648:ultrastructure; D008854:Microscopy, Electron; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D014122:Toxoplasma / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D003598:Cytoskeletal Proteins; C435912:IMC1 protein, Toxoplasma gondii; C435913:IMC2 protein, Toxoplasma gondii; D015800:Protozoan Proteins