Isothiazologuanosine (tzG) as Environmentally Sensitive Fluorescent Reporter in RNA
TzG acts as an isomorphic and isofunctional substitute for guanosine, with fluorescence properties that are sensitive to local environmental changes that enable fluorescence‐based monitoring of RNA cleavage by deoxyribozymes and of site‐specific RNA methylation by a methyltransferase ribozyme.