A general strategy to red-shift green fluorescent protein-based biosensors

Nat Chem Biol. 2020 Dec;16(12):1434-1439. doi: 10.1038/s41589-020-0641-7. Epub 2020 Sep 14.

Abstract

Compared with green fluorescent protein-based biosensors, red fluorescent protein (RFP)-based biosensors are inherently advantageous because of reduced phototoxicity, decreased autofluorescence and enhanced tissue penetration. However, existing RFP-based biosensors often suffer from small dynamic ranges, mislocalization and undesired photoconversion. In addition, the choice of available RFP-based biosensors is limited, and development of each biosensor requires substantial effort. Herein, we describe a general and convenient method, which introduces a genetically encoded noncanonical amino acid, 3-aminotyrosine, to the chromophores of green fluorescent protein-like proteins and biosensors for spontaneous and efficient green-to-red conversion. We demonstrated that this method could be used to quickly expand the repertoire of RFP-based biosensors. With little optimization, the 3-aminotyrosine-modified biosensors preserved the molecular brightness, dynamic range and responsiveness of their green fluorescent predecessors. We further applied spectrally resolved biosensors for multiplexed imaging of metabolic dynamics in pancreatic β-cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Archaeal Proteins / genetics
  • Archaeal Proteins / metabolism
  • Biosensing Techniques*
  • Cell Line
  • Cloning, Molecular
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Fluorescence Resonance Energy Transfer
  • Gene Expression
  • Genetic Vectors / chemistry
  • Genetic Vectors / metabolism
  • Glucose / pharmacology
  • Green Fluorescent Proteins / analysis*
  • Green Fluorescent Proteins / biosynthesis
  • Green Fluorescent Proteins / genetics
  • Humans
  • Insulin-Secreting Cells / cytology
  • Insulin-Secreting Cells / drug effects
  • Insulin-Secreting Cells / metabolism
  • Luminescent Proteins / analysis*
  • Luminescent Proteins / biosynthesis
  • Luminescent Proteins / genetics
  • Methanocaldococcus / chemistry
  • Methanocaldococcus / enzymology
  • Mice
  • Optical Imaging / methods*
  • Protein Engineering / methods*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Red Fluorescent Protein
  • Tyrosine / analogs & derivatives*
  • Tyrosine / genetics
  • Tyrosine / metabolism
  • Tyrosine-tRNA Ligase / genetics
  • Tyrosine-tRNA Ligase / metabolism

Substances

  • Archaeal Proteins
  • Luminescent Proteins
  • Recombinant Proteins
  • Green Fluorescent Proteins
  • 3-aminotyrosine
  • Tyrosine
  • Tyrosine-tRNA Ligase
  • Glucose