Cooperative Phosphorylation of the Tumor Suppressor Phosphatase and Tensin Homologue (PTEN) by Casein Kinases and Glycogen Synthase Kinase 3β*

The phosphatase and tensin homologue (PTEN) tumor suppressor is a phosphatidylinositol D3-phosphatase that counteracts the effects of phosphatidylinositol 3-kinase and negatively regulates cell growth and survival. PTEN is itself regulated by phosphorylation on multiple serine and threonine residues in its C terminus. Previous work has implicated casein kinase 2 (CK2) as the kinase responsible for this phosphorylation. Here we showed that CK2 does not phosphorylate all sites in PTEN and that glycogen synthase kinase 3β (GSK3β) also participates in PTEN phosphorylation. Although CK2 mainly phosphorylated PTEN at Ser-370 and Ser-385, GSK3β phosphorylated Ser-362 and Thr-366. More importantly, prior phosphorylation of PTEN at Ser-370 by CK2 strongly increased its phosphorylation at Thr-366 by GSK3β, suggesting that the two may synergize. Using RNA interference, we showed that GSK3 phosphorylates PTEN in intact cells. Finally, PTEN phosphorylation was affected by insulin-like growth factor in intact cells. We concluded that multiple kinases, including CK2 and GSK3β, participate in PTEN phosphorylation and that GSK3β may provide feedback regulation of PTEN.

[1]  R. Jope,et al.  Proapoptotic Stimuli Induce Nuclear Accumulation of Glycogen Synthase Kinase-3β* , 2001, The Journal of Biological Chemistry.

[2]  H. Hanafusa,et al.  The tumor-suppressor activity of PTEN is regulated by its carboxyl-terminal region. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[3]  W. Cavenee,et al.  Growth suppression of glioma cells by PTEN requires a functional phosphatase catalytic domain. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[4]  William R. Sellers,et al.  Phosphorylation of the PTEN Tail Acts as an Inhibitory Switch by Preventing Its Recruitment into a Protein Complex* , 2001, The Journal of Biological Chemistry.

[5]  William Arbuthnot Sir Lane,et al.  Direct identification of PTEN phosphorylation sites , 2002, FEBS letters.

[6]  W. K. Alfred Yung,et al.  Identification of a candidate tumour suppressor gene, MMAC1, at chromosome 10q23.3 that is mutated in multiple advanced cancers , 1997, Nature Genetics.

[7]  S. Antonarakis,et al.  Binding of PTEN to Specific PDZ Domains Contributes to PTEN Protein Stability and Phosphorylation by Microtubule-associated Serine/Threonine Kinases* , 2005, Journal of Biological Chemistry.

[8]  P. Guldberg,et al.  Alterations of the MMAC1/PTEN gene in lymphoid malignancies. , 1998, Blood.

[9]  G. Mills,et al.  MMAC1/PTEN mutations in primary tumor specimens and tumor cell lines. , 1997, Cancer research.

[10]  Hong Sun,et al.  TEP1, encoded by a candidate tumor suppressor locus, is a novel protein tyrosine phosphatase regulated by transforming growth factor beta. , 1997, Cancer research.

[11]  J. Armitage,et al.  Recurrent abnormalities of chromosome bands 10q23–25 in non‐Hodgkin's lymphoma , 1992, Genes, chromosomes & cancer.

[12]  T. Mustelin,et al.  The Tumor Suppressor PTEN Regulates T Cell Survival and Antigen Receptor Signaling by Acting as a Phosphatidylinositol 3-Phosphatase1 , 2000, The Journal of Immunology.

[13]  K. Luo,et al.  Transfer of proteins to membranes facilitates both cyanogen bromide cleavage and two-dimensional proteolytic mapping. , 1990, Oncogene.

[14]  José Luis de la Pompa,et al.  Negative Regulation of PKB/Akt-Dependent Cell Survival by the Tumor Suppressor PTEN , 1998, Cell.

[15]  B. Burgering,et al.  Protein kinase B (c-Akt) in phosphatidylinositol-3-OH kinase signal transduction , 1995, Nature.

[16]  Tomas Mustelin,et al.  Crosstalk between cAMP-dependent kinase and MAP kinase through a protein tyrosine phosphatase , 1999, Nature Cell Biology.

[17]  M. Wigler,et al.  PTEN, a Putative Protein Tyrosine Phosphatase Gene Mutated in Human Brain, Breast, and Prostate Cancer , 1997, Science.

[18]  N. Bottini,et al.  Control of vesicle fusion by a tyrosine phosphatase , 2004, Nature Cell Biology.

[19]  Wonhwa Cho,et al.  Membrane-binding and activation mechanism of PTEN , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[20]  R. DePinho,et al.  Cellular transformation by the MSP58 oncogene is inhibited by its physical interaction with the PTEN tumor suppressor. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[21]  Andrius Kazlauskas,et al.  The protein kinase encoded by the Akt proto-oncogene is a target of the PDGF-activated phosphatidylinositol 3-kinase , 1995, Cell.

[22]  Francisca Vazquez,et al.  Phosphorylation of the PTEN Tail Regulates Protein Stability and Function , 2000, Molecular and Cellular Biology.

[23]  R. Pulido,et al.  The Tumor Suppressor PTEN Is Phosphorylated by the Protein Kinase CK2 at Its C Terminus , 2001, The Journal of Biological Chemistry.

[24]  C. Bartram,et al.  Allelotype analysis of childhood acute lymphoblastic leukemia. , 1995, Cancer research.

[25]  N. Bottini,et al.  Negative Feedback Regulation of the Tumor Suppressor PTEN by Phosphoinositide-Induced Serine Phosphorylation1 , 2002, The Journal of Immunology.

[26]  K. Tsuchida,et al.  Regulation of PTEN binding to MAGI-2 by two putative phosphorylation sites at threonine 382 and 383. , 2001, Cancer research.

[27]  A. Godzik,et al.  Tyrosine phosphorylation of VHR phosphatase by ZAP-70 , 2003, Nature Immunology.

[28]  Tomohiko Maehama,et al.  The Tumor Suppressor, PTEN/MMAC1, Dephosphorylates the Lipid Second Messenger, Phosphatidylinositol 3,4,5-Trisphosphate* , 1998, The Journal of Biological Chemistry.