Golgi-IP, a novel tool for multimodal analysis of Golgi molecular content

The Golgi plays an essential role in protein and lipid glycosylation. Golgi dysfunction is associated with a variety of diseases including cancer, neurodegeneration and cardiovascular disease. We developed a powerful immunoprecipitation technique to isolate the Golgi by tagging TMEM115. Golgi-immunoprecipitation enriched protein markers specific for the organelle with minimal contamination from other subcellular compartments. Using this technique, we characterised the Golgi proteome, metabolome and lipidome. Proteomics analysis confirmed capture of known Golgi proteins and identified additional candidates enriched in the organelle. Metabolomics analysis revealed selective enrichment of uridine-diphosphate (UDP) sugars and their derivatives and validated SLC35A2 as the subcellular transporter for UDP-hexose. Lastly, lipidomics analysis showed that phospholipids including phosphatidylcholine, phosphatidylinositol and phosphatidylserine are the top enriched Golgi lipids. Our Golgi-IP workflow provides a paradigm for multimodal analysis of Golgi molecular content with enhanced subcellular precision.