Optical recording of cellular zinc dynamics with zinc-finger-based biosensors

Abstract

In addition to serving as an essential structural component, zinc is also involved in intracellular and intercellular signaling pathways to impact a number of cellular functions. Genetically encoded zinc sensors that are specifically targeted to various subcellular compartments (ER, mitochondria, nucleus, plasma membrane, and vesicles) have been proven to provide accurate and sensitive visualization and quantification of zinc. Here we describe the methods to utilize both ratiometric and intensiometric genetically encoded zinc sensors designed based on zinc fingers for imaging and quantification of cellular free, labile zinc concentrations, [Zn2+]free. This chapter explains in detail how to quantify [Zn2+]free in live cells as well as how to monitor zinc influx in INS-1 cells stimulated with high glucose.