title: Characterization of cyclin-dependent kinases and Cdc2/Cdc28 kinase subunits in Trichomonas vaginalis.
abstract: Cyclin-dependent kinases (CDKs) have important roles in regulating key checkpoints between stages of the cell cycle. Their activity is tightly regulated through a variety of mechanisms, including through binding with cyclin proteins and the Cdc2/Cdc28 kinase subunit (CKS), and their phosphorylation at specific amino acids. Studies of the components involved in cell cycle control in parasitic protozoa are limited. Trichomonas vaginalis is the causative agent of trichomoniasis in humans and is therefore important in public health; however, some of the basic biological processes used by this organism have not been defined. Here, we characterized proteins potentially involved in cell cycle regulation in T. vaginalis. Three genes encoding protein kinases were identified in the T. vaginalis genome, and the corresponding recombinant proteins (TvCRK1, TvCRK2, TvCRK5) were studied. These proteins displayed similar sequence features to CDKs. Two genes encoding CKSs were also identified, and the corresponding recombinant proteins were found to interact with TvCRK1 and TvCRK2 by a yeast two-hybrid system. One putative cyclin B protein from T. vaginalis was found to bind to and activate the kinase activities of TvCRK1 and TvCRK5, but not TvCRK2. This work is the first characterization of proteins involved in cell cycle control in T. vaginalis.
authors.affiliation: Departamento de Biología Molecular y Biotecnología,Instituto de Investigaciones Biomédicas,Universidad Nacional Autónoma de México,04510 Ciudad de México,México.
authors.forename: Erick
authors.initials: E
authors.lastname: Amador
authors.affiliation: Departamento de Biología Molecular y Biotecnología,Instituto de Investigaciones Biomédicas,Universidad Nacional Autónoma de México,04510 Ciudad de México,México.
authors.forename: Karla
authors.initials: K
authors.lastname: López-Pacheco
authors.affiliation: Departamento de Biología Molecular y Biotecnología,Instituto de Investigaciones Biomédicas,Universidad Nacional Autónoma de México,04510 Ciudad de México,México.
authors.forename: Nataly
authors.initials: N
authors.lastname: Morales
authors.affiliation: Departamento de Genética Molecular,Instituto de Fisiología Celular,Universidad Nacional Autónoma de México,04510 Ciudad de México,México.
authors.forename: Roberto
authors.initials: R
authors.lastname: Coria
authors.affiliation: Departamento de Biología Molecular y Biotecnología,Instituto de Investigaciones Biomédicas,Universidad Nacional Autónoma de México,04510 Ciudad de México,México.
authors.forename: Imelda
authors.initials: I
authors.lastname: López-Villaseñor
mesh_terms: D000595:Amino Acid Sequence; D042846:CDC2-CDC28 Kinases / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D008958:Models, Molecular; D010766:Phosphorylation; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins; D016415:Sequence Alignment; D014247:Trichomonas Vaginitis / Q000469:parasitology*; D014246:Trichomonas vaginalis / Q000201:enzymology* / Q000235:genetics; D020798:Two-Hybrid System Techniques
chemical_list: C077833:CRK protein, protozoan; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D011494:Protein Kinases; D042846:CDC2-CDC28 Kinases; D018844:Cyclin-Dependent Kinases
keywords: 
                 Trichomonas vaginalis
              ; CRK; Cdc2/Cdc28 kinase subunit (CKS); cell cycle; cyclin-dependent kinase (CDK)