CDK9 regulates AR promoter selectivity and cell growth through serine 81 phosphorylation.

Détails

ID Serval
serval:BIB_C1BA8B560005
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
CDK9 regulates AR promoter selectivity and cell growth through serine 81 phosphorylation.
Périodique
Molecular Endocrinology
Auteur(s)
Gordon V., Bhadel S., Wunderlich W., Zhang J., Ficarro S.B., Mollah S.A., Shabanowitz J., Hunt D.F., Xenarios I., Hahn W.C., Conaway M., Carey M.F., Gioeli D.
ISSN
1944-9917[electronic], 0888-8809[linking]
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
24
Numéro
12
Pages
2267-2280
Langue
anglais
Résumé
Previously we determined that S81 is the highest stoichiometric phosphorylation on the androgen receptor (AR) in response to hormone. To explore the role of this phosphorylation on growth, we stably expressed wild-type and S81A mutant AR in LHS and LAPC4 cells. The cells with increased wild-type AR expression grow faster compared with parental cells and S81A mutant-expressing cells, indicating that loss of S81 phosphorylation limits cell growth. To explore how S81 regulates cell growth, we tested whether S81 phosphorylation regulates AR transcriptional activity. LHS cells stably expressing wild-type and S81A mutant AR showed differences in the regulation of endogenous AR target genes, suggesting that S81 phosphorylation regulates promoter selectivity. We next sought to identify the S81 kinase using ion trap mass spectrometry to analyze AR-associated proteins in immunoprecipitates from cells. We observed cyclin-dependent kinase (CDK)9 association with the AR. CDK9 phosphorylates the AR on S81 in vitro. Phosphorylation is specific to S81 because CDK9 did not phosphorylate the AR on other serine phosphorylation sites. Overexpression of CDK9 with its cognate cyclin, Cyclin T, increased S81 phosphorylation levels in cells. Small interfering RNA knockdown of CDK9 protein levels decreased hormone-induced S81 phosphorylation. Additionally, treatment of LNCaP cells with the CDK9 inhibitors, 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole and Flavopiridol, reduced S81 phosphorylation further, suggesting that CDK9 regulates S81 phosphorylation. Pharmacological inhibition of CDK9 also resulted in decreased AR transcription in LNCaP cells. Collectively these results suggest that CDK9 phosphorylation of AR S81 is an important step in regulating AR transcriptional activity and prostate cancer cell growth.
Mots-clé
Androgen Receptor Antagonists/metabolism, Androgens/metabolism, Animals, COS Cells, Cell Growth Processes/genetics, Cells, Cultured, Cercopithecus aethiops, Cyclin T/biosynthesis, Cyclin T/genetics, Cyclin-Dependent Kinase 9/antagonists & inhibitors, Cyclin-Dependent Kinase 9/deficiency, Dichlororibofuranosylbenzimidazole/pharmacology, Flavonoids/pharmacology, Gene Knockdown Techniques, Hela Cells, Humans, Phosphorylation, Piperidines/pharmacology, Promoter Regions, Genetic, RNA, Small Interfering/genetics, Receptors, Androgen/genetics, Receptors, Androgen/metabolism, Serine/genetics, Serine/metabolism, Serine Endopeptidases/genetics, Serine Endopeptidases/metabolism, Transfection
Pubmed
Web of science
Open Access
Oui
Création de la notice
12/11/2010 19:37
Dernière modification de la notice
09/05/2019 0:47
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