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bioRxiv · 10.1101/112466

The stoichiometric signature of Rhodopsin-family G protein coupled receptors

Felce, J. H.·Latty, S. L.·Knox, R. G.·Mattick, S. R.·Lui, Y.·Lee, S. F.·Klenerman, D.·Davis, S. J.
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Abstract

Whether Rhodopsin-family G protein-coupled receptors (GPCRs) form dimers is highly controversial, with much data both for and against emerging from studies of mostly individual receptors. The types of large-scale comparative studies from which a consensus could eventually emerge have not previously been attempted. Here, we sought to determine the stoichiometric \"signatures\" of 60 GPCRs expressed by a single human cell-line using orthogonal bioluminescence resonance energy transfer-based and single-molecule microscopy assays. We observed that a relatively small fraction of Rhodopsin-family GPCRs behaved as dimers and that these receptors otherwise appeared to be monomeric. Mapped onto the entire family the analysis predicted that fewer than 20% of the ~700 Rhodopsin- family receptors form dimers. The clustered distribution of Rhodopsin-family dimers, and a striking correlation between receptor stoichiometry and GPCR family-size that we also identified, suggested that evolution has tended to favor the lineage expansion of monomers rather than dimers.\n\nOne Sentence SummaryAnalysis of 71 GPCRs from a single cell reveals the strong tendency of Rhodopsin-family receptors to exist as monomers rather than form dimers.

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Felce, J. H., Latty, S. L., Knox, R. G., Mattick, S. R., Lui, Y., Lee, S. F., Klenerman, D., Davis, S. J.. 2017-03-02. The stoichiometric signature of Rhodopsin-family G protein coupled receptors. https://doi.org/10.1101/112466

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