Fig. 1. Immunoadsorption of phogrin.EGFP-containing vesicles from INS-1 cell homogenates. Cells were infected with the phogrin.EGFP adenoviral construct and homogenised 24 hours after infection (Hom.). Phogrin.EGFP-containing vesicles were then immunoadsorbed using a polyclonal anti-phogrin antibody (P), a monoclonal anti-EGFP antibody (GFP), or an irrelevant monoclonal anti-sterol response element binding protein 1 (SREBP1) antibody (Cont). The immunoadsorbed vesicles were analysed by 7.5-15% SDS-PAGE and immunoblotting. The blots were probed with: (a) an anti-phogrin antibody; (b) an anti-EGFP antibody; (c) an anti-insulin antibody; (d) an anti-glycerol phosphate dehydrogenase (mGPDH) antibody to detect mitochondrial contamination; or (e) an anti-manose-6-phosphate receptor (M6PR) antibody for identifying lysosomal contamination. Molecular weight markers are indicated on the left and arrows show the position of phogrin.EGFP (a,b).