Fluorescent Biosensors for Multiplexed Imaging of Phosphoinositide Dynamics

ACS Chem Biol. 2020 Jan 17;15(1):33-38. doi: 10.1021/acschembio.9b00691. Epub 2020 Jan 6.

Abstract

Phosphoinositides constitute a critical family of lipids that regulate numerous cellular processes. Phosphatidylinositol 4,5-bisphosphate (PIP2) is arguably the most important plasma membrane phosphoinositide and is involved in regulating diverse processes. It is also the precursor of phosphatidylinositol 3,4,5-trisphosphate (PIP3), which is critical for growth factor signaling, as well as membrane polarization and dynamics. Studying these lipids remains challenging, because of their compartmentalized activities and location-dependent signaling profiles. Here, we introduce several new genetically encoded fluorescent biosensors, including FRET-based and dimerization-dependent fluorescent protein (ddFP)-based biosensors, that enable real-time monitoring of PIP2 levels in live cells. In addition, we developed a red fluorescent biosensor for 3-phosphoinositides that can be co-imaged with the green PIP2 indicator. Simultaneous visualization of the dynamics of PIP2 and 3-phosphoinositides in the same cell shows that plasma membrane PIP3 formation upon EGF stimulation is coupled to a decrease in the local pool of PIP2.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Biosensing Techniques
  • Cell Line
  • Cell Membrane / metabolism
  • Escherichia coli
  • Fluorescence Resonance Energy Transfer
  • Fluorescent Dyes / chemistry*
  • Humans
  • Kinetics
  • Luminescent Proteins / chemistry
  • Luminescent Proteins / genetics
  • Optical Imaging / methods*
  • Phosphatidylinositols / analysis*
  • Protein Domains
  • Signal Transduction

Substances

  • Fluorescent Dyes
  • Luminescent Proteins
  • Phosphatidylinositols