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Fully quantified spectral imaging reveals in vivo membrane protein interactions.

ABSTRACT: Here we introduce the fully quantified spectral imaging (FSI) method as a new tool to probe the stoichiometry and stability of protein complexes in biological membranes. The FSI method yields two dimensional membrane concentrations and FRET efficiencies in native plasma membranes. It can be used to characterize the association of membrane proteins: to differentiate between monomers, dimers, or oligomers, to produce binding (association) curves, and to measure the free energies of association in the membrane. We use the FSI method to study the lateral interactions of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2), a member of the receptor tyrosine kinase (RTK) superfamily, in plasma membranes, in vivo. The knowledge gained through the use of the new method challenges the current understanding of VEGFR2 signaling.

SUBMITTER: King C

PROVIDER: S-EPMC4755892 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Fully quantified spectral imaging reveals in vivo membrane protein interactions.

King Christopher C Stoneman Michael M Raicu Valerica V Hristova Kalina K

Integrative biology : quantitative biosciences from nano to macro 20160120 2

Here we introduce the fully quantified spectral imaging (FSI) method as a new tool to probe the stoichiometry and stability of protein complexes in biological membranes. The FSI method yields two dimensional membrane concentrations and FRET efficiencies in native plasma membranes. It can be used to characterize the association of membrane proteins: to differentiate between monomers, dimers, or oligomers, to produce binding (association) curves, and to measure the free energies of association in ...[more]

PMID: 26787445

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