Intracellular bioorthogonal labeling of glucagon receptor via tetrazine ligation.

ABSTRACT: The third intracellular loop (ICL3) in the cytosolic face of glucagon receptor (GCGR) experiences significant conformational transition during receptor activation. It thus offers an attractive site for the introduction of organic fluorophores in our efforts to construct fluorescence-based GPCR biosensors. Herein, we report our confocal microscopic study of intracellular fluorescent labeling of ICL3 using a bioorthogonal chemistry strategy. Our approach involves the site-specific introduction of a strained alkene amino acid into the ICL3 through genetic code expansion, followed by a highly specific inverse electron-demand Diels-Alder reaction with the fluorescent tetrazine probes. Among the three strained alkene amino acids examined, both SphK and 2'-aTCOK offered successful fluorescent lab

SUBMITTER: Tian Y 

PROVIDER: S-EPMC8488902 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature