TY - JOUR
T1 - Receptor protein tyrosine phosphatases are novel components of a polycystin complex
AU - Boucher, Catherine A.
AU - Ward, Heather H.
AU - Case, Ruth L.
AU - Thurston, Katie S.
AU - Li, Xiaohong
AU - Needham, Andrew
AU - Romero, Elsa
AU - Hyink, Deborah
AU - Qamar, Seema
AU - Roitbak, Tamara
AU - Powell, Samantha
AU - Ward, Christopher
AU - Wilson, Patricia D.
AU - Wandinger-Ness, Angela
AU - Sandford, Richard N.
N1 - Funding Information:
This work was supported by grants from The National Kidney Research Fund (now Kidney Research UK) , The Wellcome Trust, NIDDK ( R01 DK50141 ), PKD Foundation ( 12(A-C)2R ) and NIH ( DK P0162345 ). RS is a former Wellcome Trust Senior Fellow in Clinical Research. KST was a Wellcome Trust Prize Student. TR (F758) and HHW (552883) were supported by National Kidney Foundation Fellowships. Cell lines were the kind gifts of multiple individuals: A431 cells from Dr. Folma Buss, University of Cambridge; IMCD3 cells from Dr. John H. Schwartz, Boston University School of Medicine; immortalized renal cortical tubular epithelial cells (RCTEC) and PKD9-12D cells from Dr. Loghman-Adham. Antibody 17G7.2 and E1/2 were kindly supplied by Prof. M. Tremblay and Prof. C. Isacke. We thank Andrew Greenberg, Barbara Bloswick, Jenny Poon, Mark Bowen and Matthew Gratian for technical assistance. For the HFCT cell work, confocal laser scanning microscopy was performed at the MSSM-Microscopy Shared Resource Facility, supported with funding from NIH-NCI shared resources grant ( 5R24 CA095823-04 ), NSF Major Research Instrumentation grant ( DBI-9724504 ) and NIH shared instrumentation grant ( 1 S10 RR0 9145-01 ); images of primary and immortalized normal human kidney and ADPKD cells were acquired in the University of New Mexico Cancer Center Fluorescence Microscopy Facility, supported as detailed on the webpage ( http://hsc.unm.edu/crtc/microscopy/acknowledgement.shtml ). Human kidneys not suited for transplant or from ADPKD patients were obtained through the National Disease Research Interchange (NDRI, Philadelphia, PA). We are indebted to the anonymous patients and their families who donated tissue through the PKD Foundation and the NDRI to make this research possible.
PY - 2011/10
Y1 - 2011/10
N2 - Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutation of PKD1 and PKD2 that encode polycystin-1 and polycystin-2. Polycystin-1 is tyrosine phosphorylated and modulates multiple signaling pathways including AP-1, and the identity of the phosphatases regulating polycystin-1 are previously uncharacterized. Here we identify members of the LAR protein tyrosine phosphatase (RPTP) superfamily as members of the polycystin-1complex mediated through extra- and intracellular interactions. The first extracellular PKD1 domain of polycystin-1 interacts with the first Ig domain of RPTPσ, while the polycystin-1 C-terminus of polycystin-1 interacts with the regulatory D2 phosphatase domain of RPTPγ. Additional homo- and heterotypic interactions between RPTPs recruit RPTPδ. The multimeric polycystin protein complex is found localised in cilia. RPTPσ and RPTPδ are also part of a polycystin-1/E-cadherin complex known to be important for early events in adherens junction stabilisation. The interaction between polycystin-1 and RPTPγ is disrupted in ADPKD cells, while RPTPσ and RPTPδ remain closely associated with E-cadherin, largely in an intracellular location. The polycystin-1 C-terminus is an in vitro substrate of RPTPγ, which dephosphorylates the c-Src phosphorylated Y4237 residue and activates AP1-mediated transcription. The data identify RPTPs as novel interacting partners of the polycystins both in cilia and at adhesion complexes and demonstrate RPTPγ phosphatase activity is central to the molecular mechanisms governing polycystin-dependent signaling.
AB - Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutation of PKD1 and PKD2 that encode polycystin-1 and polycystin-2. Polycystin-1 is tyrosine phosphorylated and modulates multiple signaling pathways including AP-1, and the identity of the phosphatases regulating polycystin-1 are previously uncharacterized. Here we identify members of the LAR protein tyrosine phosphatase (RPTP) superfamily as members of the polycystin-1complex mediated through extra- and intracellular interactions. The first extracellular PKD1 domain of polycystin-1 interacts with the first Ig domain of RPTPσ, while the polycystin-1 C-terminus of polycystin-1 interacts with the regulatory D2 phosphatase domain of RPTPγ. Additional homo- and heterotypic interactions between RPTPs recruit RPTPδ. The multimeric polycystin protein complex is found localised in cilia. RPTPσ and RPTPδ are also part of a polycystin-1/E-cadherin complex known to be important for early events in adherens junction stabilisation. The interaction between polycystin-1 and RPTPγ is disrupted in ADPKD cells, while RPTPσ and RPTPδ remain closely associated with E-cadherin, largely in an intracellular location. The polycystin-1 C-terminus is an in vitro substrate of RPTPγ, which dephosphorylates the c-Src phosphorylated Y4237 residue and activates AP1-mediated transcription. The data identify RPTPs as novel interacting partners of the polycystins both in cilia and at adhesion complexes and demonstrate RPTPγ phosphatase activity is central to the molecular mechanisms governing polycystin-dependent signaling.
KW - Adherens junctions
KW - G-protein coupled signaling
KW - Polycystins
KW - Primary cilium
KW - Tyrosine kinase
KW - Tyrosine phosphatase
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U2 - 10.1016/j.bbadis.2010.11.006
DO - 10.1016/j.bbadis.2010.11.006
M3 - Article
C2 - 21126580
AN - SCOPUS:80052264443
SN - 0925-4439
VL - 1812
SP - 1225
EP - 1238
JO - Biochimica et Biophysica Acta - Molecular Basis of Disease
JF - Biochimica et Biophysica Acta - Molecular Basis of Disease
IS - 10
ER -