title: Role of the carboxyl terminus on the catalytic activity of protein kinase CK2alpha subunit.
abstract: Protein kinase CK2 (also known as casein kinase 2) has catalytic (alpha, alpha') and regulatory (beta) subunits. The role of carboxyl amino acids in positions from 324 to 328 was studied for Xenopus laevis CK2alpha. Deletions and mutations of these residues were produced in recombinant CK2alpha, which was assayed for kinase activity. Activity dropped 7000-fold upon deletion of amino acids 324-328. The key residues are isoleucine 327 and phenylalanine 324. A three dimensional model of CK2alpha indicates that these hydrophobic residues of helix alphaN may interact with hydrophobic residues in helix alphaE which is linked to the catalytic center.
authors.affiliation: Programa de Biologi;a Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
authors.forename: Julio
authors.initials: J
authors.lastname: Tapia
authors.forename: Germaine
authors.initials: G
authors.lastname: Jacob
authors.forename: Catherine C
authors.initials: CC
authors.lastname: Allende
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Allende
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D047390:Casein Kinase II; D002384:Catalysis; D020134:Catalytic Domain; D004795:Enzyme Stability; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008958:Models, Molecular; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D021122:Protein Subunits; D014981:Xenopus
chemical_list: D021122:Protein Subunits; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases