Poly(ADP-ribosyl)ation of p53 in vitro and in vivo modulates binding to its DNA consensus sequence.
The tumor-suppressor p53 undergoes extensive poly(ADP-ribosyl)ation early during apoptosis in human osteosarcoma cells, and degradation of poly(ADP-ribose) (PAR) attached to p53 coincides with poly(ADP-ribose)polymerase-1, (PARP-1) cleavage, and expression of p53 target genes. The mechanism by which poly(ADP-ribosyl)ation may regulate p53 function has now been investigated. Purified wild-type PARP-1 catalyzed the poly(ADP-ribosyl) of full-length p53 in vitro. In gel supershift assays, poly(ADP-ribosyl)ation suppressed p53 binding to its DNA consensus sequence; however, when p53 remained unmodified in the presence of inactive mutant PARP-1, it retained sequence-specific DNA binding activity. Poly(ADP-ribosyl)ation of p53 by PARP-1 during early apoptosis in osteosarcoma cells also inhibited p53 interaction with its DNA consensus sequence; thus, poly(ADP-ribosyl)ation may represent a novel means for regulating transcriptional activation by p53 in vivo.
Simbulan-Rosenthal
C M
CM
Department of Biochemistry and Molecular Biology, Georgetown University School of Medicine, Washington, DC 20007, USA.
Rosenthal
D S
DS
Luo
R B
RB
Samara
R
R
Jung
M
M
Dritschilo
A
A
Spoonde
A
A
Smulson
M E
ME
D017209:Apoptosis / Q000502:physiology; D001483:Base Sequence; D001859:Bone Neoplasms / Q000378:metabolism* / Q000473:pathology; D016384:Consensus Sequence; D004247:DNA / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018390:Gene Targeting; D006801:Humans; D015151:Immunoblotting; D012516:Osteosarcoma / Q000378:metabolism* / Q000473:pathology; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000502:physiology*
D004268:DNA-Binding Proteins; D016159:Tumor Suppressor Protein p53; D011064:Poly Adenosine Diphosphate Ribose; D004247:DNA; D011065:Poly(ADP-ribose) Polymerases