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Detection of Heterodimerization of Protein Isoforms Using an in Situ Proximity Ligation Assay
Published on: October 20, 2018
Small-molecule control of protein function through Staudinger reduction
Ji Luo1, Qingyang Liu1, Kunihiko Morihiro1
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Abstract:
Using small molecules to control the function of proteins in live cells with complete specificity is highly desirable, but challenging. Here we report a small-molecule switch that can be used to control protein activity. The approach uses a phosphine-mediated Staudinger reduction to activate protein function. Genetic encoding of an ortho-azidobenzyloxycarbonyl amino acid using a pyrrolysyl transfer RNA synthetase/tRNACUA pair in mammalian cells enables the site-specific introduction of a small-molecule-removable protecting group into the protein of interest. Strategic placement of this group renders the protein inactive until deprotection through a bioorthogonal Staudinger reduction delivers the active wild-type protein. This developed methodology was applied to the conditional control of several cellular processes, including bioluminescence (luciferase), fluorescence (enhanced green fluorescent protein), protein translocation (nuclear localization sequence), DNA recombination (Cre) and gene editing (Cas9).
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