TEDS Site Phosphorylation of the Yeast Myosins I Is Required for Ligand-induced but Not for Constitutive Endocytosis of the G Protein-coupled Receptor Ste2p*

  1. Bianka L. Grosshans ‡ 1 ,
  2. Helga Grötsch ‡ § 2 ,
  3. Debdyuti Mukhopadhyay ,
  4. Isabel M. Fernández § 3 ,
  5. Jens Pfannstiel ‡ ,
  6. Fatima-Zahra Idrissi ‡ § 4 ,
  7. Johannes Lechner ‡ ,
  8. Howard Riezman and
  9. M. Isabel Geli ‡ § 5
  1. §Institut de Biologia Molecular de Barcelona (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain, ‡Biochemie-Zentrum Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany, and Département de Biochimie, Sciences II, 30 Quai Ernest-Ansermet, 1211 Genève, Switzerland
  1. 5 To whom correspondence should be addressed: Institut de Biologia Molecular de Barcelona (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain. Tel.: 34934006100; Fax: 34932045904; E-mail: mgfbmc{at}ibmb.csic.es.

Abstract

The yeast myosins I Myo3p and Myo5p have well established functions in the polarization of the actin cytoskeleton and in the endocytic uptake of the G protein-coupled receptor Ste2p. A number of results suggest that phosphorylation of the conserved TEDS serine of the myosin I motor head by the Cdc42p activated p21-activated kinases Ste20p and Cla4p is required for the organization of the actin cytoskeleton. However, the role of this signaling cascade in the endocytic uptake has not been investigated. Interestingly, we find that Myo5p TEDS site phosphorylation is not required for slow, constitutive endocytosis of Ste2p, but it is essential for rapid, ligand-induced internalization of the receptor. Our results strongly suggest that a kinase activates the myosins I to sustain fast endocytic uptake. Surprisingly, however, despite the fact that only p21-activated kinases are known to phosphorylate the conserved TEDS site, we find that these kinases are not essential for ligand-induced internalization of Ste2p. Our observations indicate that a different signaling cascade, involving the yeast homologues of the mammalian PDK1 (3-phosphoinositide-dependent-protein kinase-1), Phk1p and Pkh2p, and serum and glucocorticoid-induced kinase, Ypk1p and Ypk2p, activate Myo3p and Myo5p for their endocytic function.

Footnotes

  • ↵6 The abbreviations used are: PAK, p21-activated kinase; X-gal, 5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside; 1NM-PP1, 4-amino-1-tert-butyl-3-(1-napthylmethyl)-pyrazolo[3,4-d]pyrimidine; CPY, carboxypeptidase Y; IP, immunoprecipitation; HA, hemagglutinin; GST, glutathione S-transferase; TRITC, tetramethylrhodamine isothiocyanate; MALDI, matrix-assisted laser desorption ionization; TOF, time-of-flight; SGK, serum and glucocorticoid-induced kinase.

  • ↵* This work was supported by Deutsche Forschungsgemeinschaft Grants SFB 352 and Grossgeräteinitiative and Ministero de Ciencia y Tecnología Grant SAF2002-04707. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

  • ↵1 Present address: Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520.

  • ↵2 Recipient of a predoctoral fellowship from the Generalitat de Catalunya.

  • ↵3 Recipient of a predoctoral fellowship from the Ministero de Educacíon y Ciencia (MEC).

  • ↵4 A Ramon y Cajal postdoctoral fellow supported by the MEC.

    • Received August 12, 2005.
    • Revision received February 9, 2006.
View this article with LENS
Table of Contents

This Article

  1. First Published on February 13, 2006 doi: 10.1074/jbc.M508933200 The Journal of Biological Chemistry 281, 11104-11114.
  1. » Abstract(Free)
  2. Full Text(Free)
  3. PDF(Free)
  4. All Versions of this Article:
    1. M508933200v1
    2. 281/16/11104 (most recent)

Article Usage Stats

  1. Article Usage Statistics

Submit your work to JBC.

You'll be in good company.