Imaging protein interactions in vivo with sub-cellular resolution

Valerica Raicu; Michael R. Stoneman; Russell Fung; Mike Melnichuk; David B. Jansma; Luca Pisterzi; Michael Fox; James W. Wells; Dilano K. Saldin

arXiv · 0810.2341

Imaging protein interactions in vivo with sub-cellular resolution

Valerica Raicu·Michael R. Stoneman·Russell Fung·Mike Melnichuk·David B. Jansma·Luca Pisterzi·Michael Fox·James W. Wells·Dilano K. Saldin

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Abstract

Resonant Energy Transfer (RET) from an optically excited donor molecule (D) to a non-excited acceptor molecule (A) residing nearby is widely used to detect molecular interactions in living cells. Stoichiometric information, such as the number of proteins forming a complex, has been obtained so far for a handful of proteins, but only after exposing the sample sequentially to at least two different excitation wavelengths. During this lengthy process of measurement, the molecular makeup of a cellular region may change, and this has so far limited the applicability of RET to determination of cellular averages. Here we demonstrate a method for imaging protein complex distribution in living cells with sub-cellular spatial resolution, which relies on a spectrally-resolved two-photon microscope, a simple but competent theory, and a keen selection of fluorescent tags. This technology may eventually lead to tracking dynamics of macromolecular complex formation and dissociation with spatial resolution inside living cells.

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Valerica Raicu, Michael R. Stoneman, Russell Fung, Mike Melnichuk, David B. Jansma, Luca Pisterzi, Michael Fox, James W. Wells, Dilano K. Saldin. 2008-10-14. Imaging protein interactions in vivo with sub-cellular resolution. https://arxiv.org/abs/0810.2341

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