INCREASED AND ALTERED DNA-BINDING OF HUMAN P53 BY S AND G2/M BUT NOT G1 CYCLIN-DEPENDENT KINASES

CENTRAL to the role of p53 in cell regulation are its sequence-specific interactions with genes that control the cell cycle and apoptosis(1,2). p53 response elements contain two or more copies of a somewhat promiscuous consensus sequence: 5'-XXXC(A,T)(T, A)GYYY-3' (where X is a purine and Y is a pyrimidine) (ref, 3), The sequence-specific DNA-binding region of p53 resides in its central conserved region(4). Although this region itself is not known to he phosphorylated, the amino and carboxy termini of human p53 contain sites for phosphorylation by several protein kinases.