Caged compounds are light-sensitive probes that functionally encapsulate biomolecules in an inactive form. Irradiation liberates the trapped molecule, permitting targeted perturbation of a biological process. Uncaging technology and fluorescence microscopy are 'optically orthogonal': the former allows control, and the latter, observation of cellular function. Used in conjunction with other technologies (for example, patch clamp and/or genetics), the light beam becomes a uniquely powerful tool to stimulate a selected biological target in space or time. Here I describe important examples of widely used caged compounds, their design features and synthesis, as well as practical details of how to use them with living cells.
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In vivo spatiotemporal control of voltage-gated ion channels by using photoactivatable peptidic toxins
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The Ellis-Davies laboratory is supported by grants from the US National Institutes of Health GM53395, GM65473 and MH0717505.
G.C.R.E.-D. has patents on NP-EGTA and DM-nitrophen, and preliminary patent declarations have been filed on NDBF and CDNI.
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Ellis-Davies, G. Caged compounds: photorelease technology for control of cellular chemistry and physiology. Nat Methods 4, 619–628 (2007). https://doi.org/10.1038/nmeth1072
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