Crystal structure and mutational analysis of the human CDK2 kinase complex with cell cycle-regulatory protein CksHs1.
The 2.6 Angstrom crystal structure for human cyclin-dependent kinase 2(CDK2) in complex with CksHs1, a human homolog of essential yeast cell cycle-regulatory proteins suc1 and Cks1, reveals that CksHs1 binds via all four beta strands to the kinase C-terminal lobe. This interface is biologically critical, based upon mutational analysis, but far from the CDK2 N-terminal lobe, cyclin, and regulatory phosphorylation sites. CDK2 binds the Cks single domain conformation and interacts with conserved hydrophobic residues plus His-60 and Glu-63 in their closed beta-hinge motif conformation. The beta hinge opening to form the Cks beta-interchanged dimer sterically precludes CDK2 binding, providing a possible mechanism regulating CDK2-Cks interactions. One face of the complex exposes the sequence-conserved phosphate-binding region on Cks and the ATP-binding site on CDK2, suggesting that CKs may target CDK2 to other phosphoproteins during the cell cycle.
Bourne
Y
Y
Department of Molecular Biology, Scripps Research Institute, La Jolla, California, 92037, USA.
Watson
M H
MH
Hickey
M J
MJ
Holmes
W
W
Rocque
W
W
Reed
S I
SI
Tainer
J A
JA
D001483:Base Sequence; D042846:CDC2-CDC28 Kinases; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins; D017124:Conserved Sequence; D003461:Crystallography; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004252:DNA Mutational Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000502:physiology; D011487:Protein Conformation; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012680:Sensitivity and Specificity; D017386:Sequence Homology, Amino Acid
C093090:CKS1B protein, human; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C083689:CKS2 protein, human; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases