We detected a protein in rabbit skeletal muscle extracts that was phosphorylated rapidly by SGK1 (serum- and glucocorticoid-induced kinase 1), but not by protein kinase Bα, and identified it as NDRG2 (N-myc downstream-regulated gene 2). SGK1 phosphorylated NDRG2 at Thr330, Ser332 and Thr348in vitro. All three residues were phosphorylated in skeletal muscle from wild-type mice, but not from mice that do not express SGK1. SGK1 also phosphorylated the related NDRG1 isoform at Thr328, Ser330 and Thr346 (equivalent to Thr330, Ser332 and Thr348 of NDRG2), as well as Thr356 and Thr366. Residues Thr346, Thr356 and Thr366 are located within identical decapeptide sequences GTRSRSHTSE, repeated three times in NDRG1. These threonines were phosphorylated in NDRG1 in the liver, lung, spleen and skeletal muscle of wild-type mice, but not in SGK1−/− mice. Knock-down of SGK1 in HeLa cells using small interfering RNA also suppressed phosphorylation of the threonine residues in the repeat region of NDRG1. The phosphorylation of NDRG1 by SGK1 transformed it into an excellent substrate for GSK3 (glycogen synthase kinase 3), which could then phosphorylate Ser342, Ser352 and Ser362 in the repeat region. Incubation of HeLa cells with the specific GSK3 inhibitor CT 99021 increased the electrophoretic mobility of NDRG1 in HeLa cells, demonstrating that this protein is phosphorylated by GSK3 in cells. Our results identify NDRG1 and NDRG2 as physiological substrates for SGK1, and demonstrate that phosphorylation of NDRG1 by SGK1 primes it for phosphorylation by GSK3.
Skip Nav Destination
Article navigation
December 2004
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
Research Article|
December 07 2004
Exploitation of KESTREL to identify NDRG family members as physiological substrates for SGK1 and GSK3
James T. MURRAY;
James T. MURRAY
1
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
1To whom correspondence should be addressed (email j.t.c.murray@dundee.ac.uk).
Search for other works by this author on:
David G. CAMPBELL;
David G. CAMPBELL
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Nicholas MORRICE;
Nicholas MORRICE
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Gillian C. AULD;
Gillian C. AULD
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Natalia SHPIRO;
Natalia SHPIRO
†Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Rodolpho MARQUEZ;
Rodolpho MARQUEZ
†Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Mark PEGGIE;
Mark PEGGIE
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Jenny BAIN;
Jenny BAIN
‡Division of Signal Transduction Therapy, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Graham B. BLOOMBERG;
Graham B. BLOOMBERG
§Department of Biochemistry, Medical School, University of Bristol, Bristol BS8 1TD, U.K.
Search for other works by this author on:
Florian GRAHAMMER;
Florian GRAHAMMER
∥Department of Physiology I, University of Tübingen, Tübingen, Germany
Search for other works by this author on:
Florian LANG;
Florian LANG
∥Department of Physiology I, University of Tübingen, Tübingen, Germany
Search for other works by this author on:
Peer WULFF;
Peer WULFF
¶Department of Clinical Neurobiology, University of Heidelberg, Heidelberg, Germany
Search for other works by this author on:
Dietmar KUHL;
Dietmar KUHL
**Department of Biology, Chemistry and Pharmacy, Free University of Berlin, Berlin, Germany
Search for other works by this author on:
Philip COHEN
Philip COHEN
*MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
†Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
‡Division of Signal Transduction Therapy, University of Dundee, Dundee DD1 5EH, Scotland, U.K.
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
June 26 2004
Revision Received:
September 24 2004
Accepted:
October 04 2004
Accepted Manuscript online:
October 04 2004
Online ISSN: 1470-8728
Print ISSN: 0264-6021
The Biochemical Society, London
2004
Biochem J (2004) 384 (3): 477–488.
Article history
Received:
June 26 2004
Revision Received:
September 24 2004
Accepted:
October 04 2004
Accepted Manuscript online:
October 04 2004
Citation
James T. MURRAY, David G. CAMPBELL, Nicholas MORRICE, Gillian C. AULD, Natalia SHPIRO, Rodolpho MARQUEZ, Mark PEGGIE, Jenny BAIN, Graham B. BLOOMBERG, Florian GRAHAMMER, Florian LANG, Peer WULFF, Dietmar KUHL, Philip COHEN; Exploitation of KESTREL to identify NDRG family members as physiological substrates for SGK1 and GSK3. Biochem J 15 December 2004; 384 (3): 477–488. doi: https://doi.org/10.1042/BJ20041057
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.