title: Identification of a piroplasm protein of Theileria orientalis that binds to bovine erythrocyte band 3.
abstract: Theileria orientalis infects cattle and causes various disease symptoms, including anaemia and icterus. The erythrocytic stages are responsible for these symptoms but the molecular events involved in these stages have not yet been fully elucidated. In this study, we identified a T. orientalis cDNA that encodes a polypeptide related to identity to the microneme-rhoptry protein of Theileria parva. Analysis of its recombinant product (ToMRP) by indirect fluorescent-antibody test revealed that it is specifically expressed at the early erythrocytic stage after invasion. This expression disappears during the intermediate stages of intra-erythrocytic development. Its expression then reappears at the late stages after the parasite has divided by binary fission into diad or tetrad forms and before these forms are released from the host erythrocyte. In vitro erythrocyte binding assays showed that ToMRP associates with the Triton X-insoluble fraction of erythrocytes membrane but not with intact erythrocytes. Cosedimentation and Western blot analyses revealed that ToMRP binds to band 3, a membrane component of bovine erythrocytes. These observations suggest that ToMRP may be involved in the parasite's egress from and/or invasion into the host erythrocytes by interacting with a protein in the membrane skeleton of the erythrocyte and thereby modifying the structure and function of the cell.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Jung-Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yokoyama
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kumar
authors.forename: Noboru
authors.initials: N
authors.lastname: Inoue
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Inaba
authors.forename: Kozo
authors.initials: K
authors.lastname: Fujisaki
authors.forename: Chihiro
authors.initials: C
authors.lastname: Sugimoto
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism*; D001483:Base Sequence; D002417:Cattle; D018076:DNA, Complementary / Q000235:genetics; D016054:DNA, Protozoan / Q000235:genetics; D004912:Erythrocytes / Q000378:metabolism / Q000469:parasitology; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D011485:Protein Binding; D015800:Protozoan Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D016794:Theileria / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D013801:Theileriasis / Q000097:blood / Q000469:parasitology
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D018076:DNA, Complementary; D016054:DNA, Protozoan; D015800:Protozoan Proteins; D011994:Recombinant Proteins