title: Cloning of a cdc2-related protein kinase from Trypanosoma cruzi that interacts with mammalian cyclins.
abstract: Two cdc2-related protein kinases (crk), tzcrk3 and tzcrk1, from the protozoan parasite Trypanosoma cruzi were cloned. tzcrk3 encodes a 35 kDa protein sharing 51.5% amino acid identity with human cdc2 and 82% identity with Trypanosoma brucei CRK3. tzcrk1 encodes a 33 kDa protein sharing 52.7% identity with human cdc2 and a high degree of identity (> 78%) with T. brucei CRK1, Leishmania mexicana CRK1 and Trypanosoma congolense CRK1. A recombinant TzCRK1 protein was able to phosphorylate histone HI and retinoblastoma protein. Western blotting using a polyclonal antibody raised against the recombinant TzCRK1 protein showed that the kinase is present in all life cycle stages of the parasite. A PSTAIRE antiserum detected proteins of 32, 33 and 35 kDa, with differential expression in the life cycle of the parasite. Transfection of COS-7 cells with tzcrk1 demonstrated for the first time that a CRK protein can bind mammalian cyclins; TzCRK1 co-immunoprecipitated with cyclins E, D3 and A suggesting a role for this kinase in cell cycle control. These results indicate that T. cruzi might have cyclin homologues that control the activity of the CRK proteins and that a complex mechanism would exist in order to regulate the kinases involved in the cell cycle and the differentiation processes of the parasite.
authors.affiliation: Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI, CONICET) and Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Argentina.
authors.forename: E B
authors.initials: EB
authors.lastname: Gómez
authors.forename: A R
authors.initials: AR
authors.lastname: Kornblihtt
authors.forename: M T
authors.initials: MT
authors.lastname: Téllez-Iñón
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D016203:CDC2 Protein Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D019556:COS Cells; D003001:Cloning, Molecular; D016213:Cyclins / Q000378:metabolism*; D017125:Genes, Protozoan; D005816:Genetic Complementation Test; D006657:Histones / Q000378:metabolism; D006801:Humans; D015336:Molecular Probe Techniques; D008969:Molecular Sequence Data; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism; D016415:Sequence Alignment; D014162:Transfection; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development
chemical_list: C077833:CRK protein, protozoan; D016213:Cyclins; D006657:Histones; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D016160:Retinoblastoma Protein; D011494:Protein Kinases; C112574:TCRK3 protein, Trypanosoma cruzi; C112575:tcrk1 protein, Trypanosoma cruzi; D016203:CDC2 Protein Kinase