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Acquiring snapshots of the orientation of trans-membrane protein domains using a hybrid FRET pair.

ABSTRACT: One challenge in studying the function of membrane-embedded proteins is determining the orientation of key domains in the context of the changing and dynamic membrane environment. We describe a confocal microscopy setup that utilizes external electric field pulses to direct dipicrylamine (DPA) to a membrane leaflet. The detection of FRET between DPA and a fluorescent probe attributes it to the inner or outer leaflet of a membrane. By utilizing short acquisition times and confocal imaging, this attribution could be made even in changing membrane environments. Our setup adds versatility to the study of the biological activity of membrane-embedded proteins.

SUBMITTER: Gahl RF

PROVIDER: S-EPMC4373971 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Acquiring snapshots of the orientation of trans-membrane protein domains using a hybrid FRET pair.

Gahl Robert F RF Tekle Ephrem E Zhu Gefei Alex GA Taraska Justin W JW Tjandra Nico N

FEBS letters 20150303 8

One challenge in studying the function of membrane-embedded proteins is determining the orientation of key domains in the context of the changing and dynamic membrane environment. We describe a confocal microscopy setup that utilizes external electric field pulses to direct dipicrylamine (DPA) to a membrane leaflet. The detection of FRET between DPA and a fluorescent probe attributes it to the inner or outer leaflet of a membrane. By utilizing short acquisition times and confocal imaging, this a ...[more]

PMID: 25747388

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