Combining LOPIT with differential ultracentrifugation for high-resolution spatial proteomics

Nat Commun. 2019 Jan 18;10(1):331. doi: 10.1038/s41467-018-08191-w.

Abstract

The study of protein localisation has greatly benefited from high-throughput methods utilising cellular fractionation and proteomic profiling. Hyperplexed Localisation of Organelle Proteins by Isotope Tagging (hyperLOPIT) is a well-established method in this area. It achieves high-resolution separation of organelles and subcellular compartments but is relatively time- and resource-intensive. As a simpler alternative, we here develop Localisation of Organelle Proteins by Isotope Tagging after Differential ultraCentrifugation (LOPIT-DC) and compare this method to the density gradient-based hyperLOPIT approach. We confirm that high-resolution maps can be obtained using differential centrifugation down to the suborganellar and protein complex level. HyperLOPIT and LOPIT-DC yield highly similar results, facilitating the identification of isoform-specific localisations and high-confidence localisation assignment for proteins in suborganellar structures, protein complexes and signalling pathways. By combining both approaches, we present a comprehensive high-resolution dataset of human protein localisations and deliver a flexible set of protocols for subcellular proteomics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Fractionation
  • Cell Line, Tumor
  • Centrifugation, Density Gradient / methods
  • Humans
  • Mass Spectrometry / methods
  • Proteome / analysis*
  • Proteomics / methods*
  • Spatial Analysis
  • Ultracentrifugation

Substances

  • Proteome