A novel association of mGluR1a with the PDZ scaffold protein CAL modulates receptor activity

FEBS Lett. 2008 Dec 24;582(30):4117-24. doi: 10.1016/j.febslet.2008.10.054. Epub 2008 Nov 21.


Metabotropic glutamate receptor subtype 1a (mGluR1a) associates with the proteins mediating its receptor activity, suggesting a complex-controlled function of mGluR1a. Here, using glutathione-S-transferase pull-down, co-immunoprecipitation and immunofluorescence assays in vitro and in vivo, we have found CFTR-associated ligand (CAL) to be a novel binding partner of mGluR1a, through its PSD95/discslarge/ZO1homology domain. Deletion of mGluR1a-carboxyl terminus (CT) or mutation of Leu to Ala in the CT of mGluR1a reduces the association, indicating the essential binding region of mGluR1a for CAL. Functionally, the interaction of mGluR1a with CAL was shown to inhibit mGluR1a-mediated ERK1/2 activation, without an apparent effect, via the C-terminal-truncated receptor. These findings might provide a novel mechanism for the regulation of mGluR1a-mediated signaling through the interaction with CAL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Animals
  • COS Cells
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Chlorocebus aethiops
  • Golgi Matrix Proteins
  • Humans
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Membrane Transport Proteins
  • Proteomics
  • Rats
  • Receptors, Metabotropic Glutamate / genetics
  • Receptors, Metabotropic Glutamate / metabolism*
  • Signal Transduction


  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • GOPC protein, human
  • Golgi Matrix Proteins
  • Membrane Proteins
  • Membrane Transport Proteins
  • Receptors, Metabotropic Glutamate
  • metabotropic glutamate receptor type 1