Substrate recognition by casein kinase-II: the role of histidine-160.
Casein kinase-II (CK-II) belongs to the protein kinases recognizing serine/threonine in proximity to acidic residues in protein substrates. Crystallography and mutagenesis studies on the cAMP-dependent protein kinase (PKA) disclosed that glutamic acid-170 (E170), is important for interaction of substrates with the enzyme. At a position corresponding to E170 in PKA most Ser/Thr kinases have an aspartic or glutamic acid, while CK-II has a histidine residue (H160). In order to examine the relevance of this substitution for CK-II substrate specificity, a mutant of the catalytic alpha subunit (H160D), in which H160 was changed to aspartic acid, was made. Our results show that H160 is not primarily involved in canonical substrate recognition, but does interact with an acidic residue located at position -2 with respect to the target Ser/Thr.
Dobrowolska
G
G
University of Washington, Department of Pharmacology, Seattle 98195.
Meggio
F
F
Marin
O
O
Lozeman
F J
FJ
Li
D
D
Pinna
L A
LA
Krebs
E G
EG
D000595:Amino Acid Sequence; D000818:Animals; D001224:Aspartic Acid / Q000235:genetics; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D047390:Casein Kinase II; D006639:Histidine / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009842:Oligopeptides / Q000138:chemical synthesis / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012694:Serine / Q000378:metabolism; D018411:Spodoptera / Q000166:cytology; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013912:Threonine / Q000378:metabolism
D009842:Oligopeptides; D011994:Recombinant Proteins; D013912:Threonine; D001224:Aspartic Acid; D012694:Serine; D006639:Histidine; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases