title: A novel association of mGluR1a with the PDZ scaffold protein CAL modulates receptor activity.
abstract: 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.
authors.affiliation: Department of Biochemistry and Molecular Biology, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069, China.
authors.forename: Jiuqin
authors.initials: J
authors.lastname: Zhang
authors.forename: Shan
authors.initials: S
authors.lastname: Cheng
authors.forename: Ying
authors.initials: Y
authors.lastname: Xiong
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Ma
authors.forename: Dali
authors.initials: D
authors.lastname: Luo
authors.forename: Andreas
authors.initials: A
authors.lastname: Jeromin
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Junqi
authors.initials: J
authors.lastname: He
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002522:Chlorocebus aethiops; D000077614:Golgi Matrix Proteins; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins; D040901:Proteomics; D051381:Rats; D018094:Receptors, Metabotropic Glutamate / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C434484:GOPC protein, human; D000077614:Golgi Matrix Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D018094:Receptors, Metabotropic Glutamate; C104077:metabotropic glutamate receptor type 1