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Lateral diffusion contributes to FRET from lanthanide-tagged membrane proteins.

ABSTRACT: Diffusion can enhance Förster resonance energy transfer (FRET) when donors or acceptors diffuse distances that are similar to the distances separating them during the donor's excited state lifetime. Lanthanide donors remain in the excited state for milliseconds, which makes them useful for time-resolved FRET applications but also allows time for diffusion to enhance energy transfer. Here we show that diffusion dramatically enhances FRET between membrane proteins labeled with lanthanide donors. This phenomenon complicates interpretation of experiments that use long-lived donors to infer association or proximity of mobile membrane proteins, but also offers a method of monitoring diffusion in membrane domains in real time in living cells.

SUBMITTER: Lan TH

PROVIDER: S-EPMC4509987 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Lateral diffusion contributes to FRET from lanthanide-tagged membrane proteins.

Lan Tien-Hung TH Wu Guangyu G Lambert Nevin A NA

Biochemical and biophysical research communications 20150625 1

Diffusion can enhance Förster resonance energy transfer (FRET) when donors or acceptors diffuse distances that are similar to the distances separating them during the donor's excited state lifetime. Lanthanide donors remain in the excited state for milliseconds, which makes them useful for time-resolved FRET applications but also allows time for diffusion to enhance energy transfer. Here we show that diffusion dramatically enhances FRET between membrane proteins labeled with lanthanide donors. T ...[more]

PMID: 26119691

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