Association of the Ku autoantigen/DNA-dependent protein kinase holoenzyme and poly(ADP-ribose) polymerase with the DNA binding domain of progesterone receptors.
J Mol Endocrinol
; 24(2): 165-82, 2000 Apr.
Article
em En
| MEDLINE
| ID: mdl-10750018
ABSTRACT
Ligand-activated progesterone receptors (PR) bind to DNA at specific progesterone response elements by means of a DNA binding domain (DBD(PR)) containing two highly conserved zinc fingers. DNA-bound PRs regulate transcription via interaction with other nuclear proteins and transcription factors. We have now identified four HeLa cell nuclear proteins that copurify with a glutathionine-S-transferase-human DBD(PR )fusion protein. Microsequence and immunoblot analyses identified one of these proteins as the 113 kDa poly(ADP-ribose) polymerase. The three other proteins were identified as subunits of the DNA-dependent protein kinase (DNA-PK) holoenzyme its DNA binding regulatory heterodimers consisting of Ku70 and Ku86, and the 460 kDa catalytic subunit, DNA-PK(CS). DNA-PK that was 'pulled-down' by DBD(PR) on the affinity resin was able to (1) autophosphorylate Ku70, Ku86, and DNA-PK(CS), (2) transphosphorylate DBD(PR), and (3) phosphorylate a DNA-PK-specific p53 peptide substrate. DNA-PK was also able to associate with the DBD of the yeast activator GAL4. However, neither a PR DBD mutant lacking a structured first zinc finger (DBD(CYS)) nor the core DBD of the estrogen receptor (DBD(ER)) copurified DNA-PK, suggesting the interaction is not non-specific for DBDs. Lastly, we found that DNA-PK copurified with full-length human PR transiently expressed in HeLa cells, suggesting that the human PR/DNA-PK complex can assemble in vivo. These data show that DNA-PK and DBD(PR) interact, that DBD(PR) is a phosphorylation substrate of DNA-PK, and suggest a potential role for DNA-PK in PR-mediated transcription.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Nucleares
/
Receptores de Progesterona
/
Poli(ADP-Ribose) Polimerases
/
Proteínas Serina-Treonina Quinases
/
DNA Helicases
/
Proteínas de Saccharomyces cerevisiae
/
Antígenos Nucleares
/
Proteínas de Ligação a DNA
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
J Mol Endocrinol
Ano de publicação:
2000
Tipo de documento:
Article