Differential palmitoylation of two mouse glutamate receptor interacting protein 1 forms with different N-terminal sequences

Glutamate receptor interacting protein (GRIP) is a member of the PDZ domain -containing protein family that is localized in the postsynaptic density ar ea. This protein has been reported to interact specifically with the C-term ini of AMPA-selective glutamate receptor channel subunits, GluR alpha2 and GluR alpha3 through its PDZ domains. To clarify the physiological functions of GRIP, we cloned mouse GRIP1, and found that there are three sites for a lternative splicing and two putative translational start codons by characte rizing GRIP1 cDNA clones and reverse transcription-polymerase chain reactio n products. Metabolic labeling of COS-7 cells expressing two N-terminal GRI P1 proteins demonstrated that these proteins differed in their pattern of p almitoylation. These findings suggested that the molecular diversity of GRI P1 underlies the localization and functional heterogeneity of this protein. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.