Human proliferating cell nuclear antigen, poly(ADP-ribose) polymerase-1, and p21waf1/cip1. A dynamic exchange of partners.
J Biol Chem
; 278(41): 39265-8, 2003 Oct 10.
Article
en En
| MEDLINE
| ID: mdl-12930846
We addressed the analysis of the physical and functional association of proliferating cell nuclear antigen (PCNA), a protein involved in many DNA transactions, with poly(ADP-ribose) polymerase (PARP-1), an enzyme that plays a crucial role in DNA repair and interacts with many DNA replication/repair factors. We demonstrated that PARP-1 and PCNA co-immunoprecipitated both from the soluble and the DNA-bound fraction isolated from S-phase-synchronized HeLa cells. Immunoprecipitation experiments with purified proteins further confirmed a physical association between PARP-1 and PCNA. To investigate the effect of this association on PARP-1 activity, an assay based on the incorporation of radioactive NAD was performed. Conversely, the effect of PARP-1 on PCNA-dependent DNA synthesis was assessed by a DNA polymerase delta assay. A marked inhibition of both reactions was found. Unexpectedly, PARP-1 activity also decreased in the presence of p21waf1/cip1. By pull-down experiments, we provided the first evidence for an association between PARP-1 and p21, which involves the C-terminal part of p21 protein. This association was further demonstrated to occur also in vivo in MNNG (N-methyl-N'-nitro-N-nitrosoguanidine)-treated human fibroblasts. These observations suggest that PARP-1 and p21 could cooperate in regulating the functions of PCNA during DNA replication/repair.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Poli(ADP-Ribosa) Polimerasas
/
Ciclinas
/
Antígeno Nuclear de Célula en Proliferación
Límite:
Humans
Idioma:
En
Revista:
J Biol Chem
Año:
2003
Tipo del documento:
Article
País de afiliación:
Italia
Pais de publicación:
Estados Unidos