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Multipronged interaction of the COG complex with intracellular membranes.

ABSTRACT: The conserved oligomeric Golgi complex is a peripheral membrane protein complex that orchestrates the tethering and fusion of intra-Golgi transport carriers with Golgi membranes. In this study we have investigated the membrane attachment of the COG complex and it's on/off dynamic on Golgi membranes. Several complimentary approaches including knock-sideways depletion, FRAP, and FLIP revealed that assembled COG complex is not diffusing from Golgi periphery in live HeLa cells. Moreover, COG subunits remained membrane-associated even in COG4 and COG7 depleted cells when Golgi architecture was severely affected. Overexpression of myc-tagged COG sub-complexes revealed that different membrane-associated COG partners including ?-COP, p115 and SNARE STX5 preferentially bind to different COG assemblies, indicating that COG subunits interact with Golgi membranes in a multipronged fashion.

SUBMITTER: Willett R

PROVIDER: S-EPMC3948154 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Multipronged interaction of the COG complex with intracellular membranes.

Willett Rose R Pokrovskaya Irina I Kudlyk Tetyana T Lupashin Vladimir V

Cellular logistics 20140101 1

The conserved oligomeric Golgi complex is a peripheral membrane protein complex that orchestrates the tethering and fusion of intra-Golgi transport carriers with Golgi membranes. In this study we have investigated the membrane attachment of the COG complex and it's on/off dynamic on Golgi membranes. Several complimentary approaches including knock-sideways depletion, FRAP, and FLIP revealed that assembled COG complex is not diffusing from Golgi periphery in live HeLa cells. Moreover, COG subunit ...[more]

PMID: 24649395

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