The mGlu3 C-terminus associates with native PICK1. A, HEK lysates expressing GFP-PICK1 or GFP were incubated with Sepharose-immobilized synthetic peptides that incorporated either the 20 C-terminal residues of the WT (mGlu3RctWT) or mutated mouse mGlu3 receptor (mGlu3ctSSD) or with Sepharose beads only. B, Protein extracts from mouse brain were incubated with the indicated Sepharose-immobilized peptides, and bound proteins were analyzed by Western blotting with an anti-PICK1 antibody. Native PICK1 expressed in mice brain coimmunoprecipitates with the mGlu3 receptor C-terminal. Representative data of three independent experiments are illustrated. Data are mean ± SEM. *p < 0.05. ***p < 0.001.