Phosphodiesterase-8A binds to and regulates Raf-1 kinase

Brown, K.M. et al. (2013) Phosphodiesterase-8A binds to and regulates Raf-1 kinase. Proceedings of the National Academy of Sciences of the United States of America, 110(16), E1533-E1542. (doi:10.1073/pnas.1303004110)

[img]
Preview
Text
77040.pdf - Published Version

1MB

Publisher's URL: http://dx.doi.org/10.1073/pnas.1303004110

Abstract

V-raf-1 murine leukemia viral oncogene homolog 1 (Raf-1) is a key activator of the ERK pathway and is a target for cross-regulation of this pathway by the cAMP signaling system. The cAMP-activated protein kinase, PKA, inhibits Raf-1 by phosphorylation on S259. Here, we show that the cAMP-degrading phosphodiesterase-8A (PDE8A) associates with Raf-1 to protect it from inhibitory phosphorylation by PKA, thereby enhancing Raf-1’s ability to stimulate ERK signaling. PDE8A binds to Raf-1 with high (picomolar) affinity. Mapping of the interaction domain on PDE8A using peptide array technology identified amino acids 454–465 as the main binding site, which could be disrupted by mutation. A cell-permeable peptide corresponding to this region disrupted the PDE8A/Raf-1 interaction in cells, thereby reducing ERK activation and the cellular response to EGF. Overexpression of a catalytically inactive PDE8A in cells displayed a dominant negative phenotype on ERK activation. These effects were recapitulated at the organism level in genetically modified (PDE8A−/−) mice. Similarly, PDE8 deletion in Drosophila melanogaster reduced basal ERK activation and sensitized flies to stress-induced death. We propose that PDE8A is a physiological regulator of Raf-1 signaling in some cells.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Christian, Dr Frank and Baillie, Professor George and Houslay, Professor Miles and Terhzaz, Dr Selim and Day, Dr Jonathan and Davies, Professor Shireen and Huston, Dr Elaine and Kolch, Prof Walter
Authors: Brown, K.M., Day, J.P., Huston, E., Zimmermann, B., Hampel, K., Christian, F., Romano, D., Terhzaz, S., Lee, L.C.Y., Willis, M.J., Morton, D.B., Beavo, J.A., Shimizu-Albergine, M., Davies, S.A., Kolch, W., Houslay, M.D., and Baillie, G.S.
College/School:College of Medical Veterinary and Life Sciences > Institute of Cardiovascular and Medical Sciences
College of Medical Veterinary and Life Sciences > Institute of Molecular Cell and Systems Biology
College of Medical Veterinary and Life Sciences > Institute of Neuroscience and Psychology
Journal Name:Proceedings of the National Academy of Sciences of the United States of America
Publisher:National Academy of Sciences
ISSN:0027-8424
ISSN (Online):1091-6490
Published Online:18 March 2013
Copyright Holders:Copyright © 2013 National Academy of Sciences
First Published:First published in Proceedings of the National Academy of Sciences of the United States of America
Publisher Policy:Reproduced in accordance with the copyright policy of the publisher
Related URLs:

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
438301Phosphodiesterase-4 isoforms - intracellular targeting, regulation and potential therapeutic targetsMiles HouslayMedical Research Council (MRC)G0600765RI NEUROSCIENCE & PSYCHOLOGY