An In Vivo Fluorescent Sensor Reveals Intracellular Ins(1,3,4,5)P₄Dynamics in Single Cells

Abstract

Don′t shoot the messenger! An optical sensor for D-myo-inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P4), an intracellular second messenger, is constructed by introducing a fluorophore at a unique cysteine residue within a mutant of the pleckstrin homology (PH) domain of the general receptor for phosphoinositides 1 (GRP1). The biosensor visualizes the Ins(1,3,4,5)P4 dynamics by agonist stimulation in single live cells.