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Directed evolution of APEX2 for electron microscopy and proximity labeling.

ABSTRACT: APEX is an engineered peroxidase that functions as an electron microscopy tag and a promiscuous labeling enzyme for live-cell proteomics. Because limited sensitivity precludes applications requiring low APEX expression, we used yeast-display evolution to improve its catalytic efficiency. APEX2 is far more active in cells, enabling the use of electron microscopy to resolve the submitochondrial localization of calcium uptake regulatory protein MICU1. APEX2 also permits superior enrichment of endogenous mitochondrial and endoplasmic reticulum membrane proteins.

SUBMITTER: Lam SS

PROVIDER: S-EPMC4296904 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Directed evolution of APEX2 for electron microscopy and proximity labeling.

Lam Stephanie S SS Martell Jeffrey D JD Kamer Kimberli J KJ Deerinck Thomas J TJ Ellisman Mark H MH Mootha Vamsi K VK Ting Alice Y AY

Nature methods 20141124 1

APEX is an engineered peroxidase that functions as an electron microscopy tag and a promiscuous labeling enzyme for live-cell proteomics. Because limited sensitivity precludes applications requiring low APEX expression, we used yeast-display evolution to improve its catalytic efficiency. APEX2 is far more active in cells, enabling the use of electron microscopy to resolve the submitochondrial localization of calcium uptake regulatory protein MICU1. APEX2 also permits superior enrichment of endog ...[more]

PMID: 25419960

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Project description:This SuperSeries is composed of the SubSeries listed below.

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