Scientific Publications

Proteomic Mapping of the Human Mitochondrial Intermembrane Space in Live Cells via Ratiometric APEX Tagging.

Publication TypeJournal Article
AuthorsHung, V., Zou P., Rhee HW, Udeshi ND, Cracan V., Svinkina T., Carr SA, Mootha VK, and Ting AY
AbstractObtaining complete protein inventories for subcellular regions is a challenge that often limits our understanding of cellular function, especially for regions that are impossible to purify and are therefore inaccessible to traditional proteomic analysis. We recently developed a method to map proteomes in living cells with an engineered peroxidase (APEX) that bypasses the need for organellar purification when applied to membrane-bound compartments; however, it was insufficiently specific when applied to unbounded regions that allow APEX-generated radicals to escape. Here, we combine APEX technology with a SILAC-based ratiometric tagging strategy to substantially reduce unwanted background and achieve nanometer spatial resolution. This is applied to map the proteome of the mitochondrial intermembrane space (IMS), which can freely exchange small molecules with the cytosol. Our IMS proteome of 127 proteins has >94% specificity and includes nine newly discovered mitochondrial proteins. This approach will enable scientists to map proteomes of cellular regions that were previously inaccessible.
Year of Publication2014
JournalMolecular cell
Volume55
Issue2
Pages332-41
Date Published (YYYY/MM/DD)2014/07/17
ISSN Number1097-2765
DOI10.1016/j.molcel.2014.06.003
PubMedhttp://www.ncbi.nlm.nih.gov/pubmed/25002142?dopt=Abstract