Poly(ADP-ribose) binds to specific domains of p53 and alters its DNA binding functions.
DNA strand breaks are potential interaction sites for the nuclear enzyme poly(ADP-ribose) polymerase (PARP; E.C. 2.4.2.30) and the tumor suppressor protein p53. Both proteins bind and respond to DNA breaks and both play a role in DNA damage signaling. A temporary colocalization and complex formation between these proteins has been demonstrated in mammalian cells. Here we show that free and poly(ADP-ribose) polymerase-bound ADP-ribose polymers target three domains in p53 protein for strong noncovalent interactions. The polymer binding sites could be mapped to two amino acid sequences in the sequence-specific core DNA binding domain of p53 (amino acid positions 153-178 and 231-253) and another one in the oligomerization domain (amino acids 326-348). In mobility shift experiments, poly(ADP-ribose) effectively prevented and reversed p53 binding to the palindromic p53 consensus sequence. Additionally, poly(ADP-ribose) also interfered with the DNA single strand end binding of p53. The results suggest that ADP-ribose polymers could play a role in regulating the DNA binding properties of p53.
Malanga
M
M
Institute of Pharmacology and Toxicology, University of Zürich-Tierspital, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland.
Pleschke
J M
JM
Kleczkowska
H E
HE
Althaus
F R
FR
D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D016384:Consensus Sequence; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006801:Humans; D051379:Mice; D000071137:Poly (ADP-Ribose) Polymerase-1; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism; D013329:Structure-Activity Relationship; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D011506:Proteins; D016159:Tumor Suppressor Protein p53; D011064:Poly Adenosine Diphosphate Ribose; C499320:PARP1 protein, human; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases