Human Molecular Genetics Advance Access originally published online on March 21, 2006
Human Molecular Genetics 2006 15(9):1465-1473; doi:10.1093/hmg/ddl070
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Identification of an N-terminal glycogen synthase kinase 3 phosphorylation site which regulates the functional localization of polycystin-2 in vivo and in vitro
1Academic Nephrology Unit, Sheffield Kidney Institute, Division of Clinical Sciences (North), University of Sheffield, Sheffield, UK and 2Department of Medicine, Metrohealth Medical Center, Case Western Reserve University, Cleveland, USA
* To whom correspondence should be addressed at: University of Sheffield, Clinical Sciences Centre, Northern General Hospital, Herries Road, Sheffield S5 7AU, UK. Tel: +44 1142714961; Fax: +44 1142560458; Email: a.ong{at}sheffield.ac.uk
Received January 5, 2006; Revised February 17, 2006; Accepted March 15, 2006
PKD2 is mutated in 15% of patients with autosomal dominant polycystic kidney disease. Polycystin-2 (PC2), the PKD2 protein, is a non-selective Ca2+-permeable cation channel which may function at the cell surface and ER. Nevertheless, the factors that regulate the dynamic translocation of PC2 between the ER and other compartments are not well understood. Constitutive phosphorylation of PC2 at a single C-terminal site (Ser812) has been previously reported. As we were unable to abolish phospholabelling of PC2 in HEK293 cells by site-directed mutagenesis of Ser812 or all five predicted phosphorylation sites in the C-terminus, we hypothesized that PC2 could also be phosphorylated at the N-terminus. In this paper, we report the identification of a new phosphorylation site for PC2 within its N-terminal domain (Ser76) and demonstrate that this residue is phosphorylated by glycogen synthase kinase 3 (GSK3). The consensus recognition sequence for GSK3 (Ser76/Ser80) is evolutionarily conserved down to lower vertebrates. In the presence of specific GSK3 inhibitors, the lateral plasma membrane pool of endogenous PC2 redistributes into an intracellular compartment in MDCK cells without any change in primary cilia localization. Finally, co-injection of wild-type but not a S76A/S80A mutant PKD2 capped mRNA could rescue the cystic phenotype induced by an antisense morpholino oligonucleotide to pkd2 in zebrafish pronephric kidney. We conclude that surface localization of PC2 is regulated by phosphorylation at a unique GSK3 site in its N-terminal domain in vivo and in vitro. This site is functionally significant for the maintenance of normal glomerular and tubular morphology.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
S. Feng, G. M. Okenka, C.-X. Bai, A. J. Streets, L. J. Newby, B. T. DeChant, L. Tsiokas, T. Obara, and A. C. M. Ong Identification and Functional Characterization of an N-terminal Oligomerization Domain for Polycystin-2 J. Biol. Chem., October 17, 2008; 283(42): 28471 - 28479. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Du, M. Ding, S. Sours-Brothers, S. Graham, and R. Ma Mediation of angiotensin II-induced Ca2+ signaling by polycystin 2 in glomerular mesangial cells Am J Physiol Renal Physiol, April 1, 2008; 294(4): F909 - F918. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Sohara, Y. Luo, J. Zhang, D. K. Manning, D. R. Beier, and J. Zhou Nek8 Regulates the Expression and Localization of Polycystin-1 and Polycystin-2 J. Am. Soc. Nephrol., March 1, 2008; 19(3): 469 - 476. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. K. Moss, G. Bellett, J. M. Carter, M. Liovic, J. Keynton, A. R. Prescott, E. B. Lane, and M. M. Mogensen Ninein is released from the centrosome and moves bi-directionally along microtubules J. Cell Sci., September 1, 2007; 120(17): 3064 - 3074. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Obara, S. Mangos, Y. Liu, J. Zhao, S. Wiessner, A. G. Kramer-Zucker, F. Olale, A. F. Schier, and I. A. Drummond Polycystin-2 Immunolocalization and Function in Zebrafish J. Am. Soc. Nephrol., October 1, 2006; 17(10): 2706 - 2718. [Abstract] [Full Text] [PDF] |
||||



