Fluoride-Triggered Protein Activation via a Genetically Encoded Tyrosine Analogue

Fluoride is orthogonal to cellular metabolism and can
serve as
an effective chemical trigger for modulating biological systems. Here,
we present a genetically encoded actuator platform based on the site-specific
incorporation of a fluoride-responsive noncanonical amino acid, dimethylthiophosphinoyl
tyrosine (DTPY), into tyrosine-dependent proteins. In superfolder
green fluorescent protein, replacement of Tyr66 with DTPY prevents
native fluorescence, which is restored upon fluoride-induced deprotection.
Similarly, incorporation of DTPY at the catalytic Tyr324 residue of
Cre recombinase enables conditional activation of site-specific DNA
recombination. This approach provides a general strategy for temporal
control of protein activity both in vitro and in
living cells, offering a versatile tool for synthetic biology and
cellular engineering.