Intracellular Pressure Measurement by using Pressure Sensitive Yellow Fluorescent Protein

Abstract

Fluorescent protein-based indicators for intracellular environment conditions such as pH and ion concentrations are commonly used to study the status and dynamics of living cells. Despite being an important factor in many biological processes, pressure, however, is an exception. Development of the pressure sensitive fluorescent protein would blaze a new path to the future biology. Recently, we enhanced the pressure sensitivity of yellow fluorescent protein (YFP) by inserting several glycines into it. Our mutation enhanced the interaction between the chromophore and the solvent that is responsible for pressure changing. In response to changes in pressure, a spectrum shift and an intensity change of the fluorescence was observed, indicating applicability of the present YFP for measuring the intracellular pressure on a live specimen. By measuring the fluorescence of the mutant YFP, we succeeded in measuring the intracellular pressure changes that follow actin filament disruption in living cells. This study shows that our mutation enhanced unknown properties of YFP that may allow us to measure the intracellular pressure.View Large Image | View Hi-Res Image | Download PowerPoint Slide