Pulldown of P180/RRBP1 interacting protein

P180/RRBP1 is an integral ER-resident protein known to be involved in mRNA binding and translation at the ER. We found that P180/RBBP1 is enriched in neuronal axons. To acquire more knowledge about its interactome and confirmation that P180/RRBP1 is interacting with ribosomes, we performed an unbiased screen of P180 interacting proteins by performing streptavidin pulldowns with GFP-biotin (GFPbio/AviTag)-tagged P180 and subsequent mass spectrometry analysis using HEK293T lysates and adult rat brain extracts. Co-transfection with a BirA construct ensures biotinylation ofP180 and allows subsequent streptavidin pulldown. A GFP-biotin/AviTag only construct was used as control conditionfor specificity.