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Figure S3. Expression of various constructs in PC12 cells. (A) Overexpression of GTPase-deficient Rab proteins. PC12 cells were transfected with vectors encoding myc-tagged Rab3A-Q81L or GFP-tagged GTPase-deficient Rab8, Rab11, Rab13, and Rab27A. 3 d after transfection, cells lysates (80 µg) were analyzed by immunoblotting using anti-Rab3A (from Synaptic Systems) or anti-GFP antibodies. Positions of molecular weight markers (x10^-3) are indicated on the right side. (B) Expression of myc-tagged Myrip constructs. PC12 cells were cotransfected with vectors encoding SERT and different MyRIP constructs (as indicated). 3 d later, cell lysates (60 µg) were analyzed by immunoblotting using anti-myc tag antibody. (C) PC12 cells were transfected with a vector encoding myc-tagged granuphilin. 3 d later, the presence of granuphilin was assayed by immunoblotting in nontransfected (mock) and transfected cells (granuphilin) using an anti-MycTag antibody. (D) Melanophilin is not expressed in PC12 cells. The presence of melanophilin was assayed by immunoblotting in control PC12 cells, human melanocytes (MNT1, provided by E. Coudrier, CNRS UMR 144, Institut Curie), and PC12 cells transfected with a plasmid encoding mouse melanophilin (IMAGp998N088782Q3, obtained from RZPD). The antiserum used was raised against the Rab binding domain of human melanophilin (unpublished data).