Red fluorescent protein-based cAMP indicator applicable to optogenetics and in vivo imaging

Sci Rep. 2017 Aug 4;7(1):7351. doi: 10.1038/s41598-017-07820-6.

Abstract

cAMP is a common second messenger that is involved in various physiological processes. To expand the colour palette of available cAMP indicators, we developed a red cAMP indicator named "Pink Flamindo" (Pink Fluorescent cAMP indicator). The fluorescence intensity of Pink Flamindo increases 4.2-fold in the presence of a saturating dose of cAMP, with excitation and emission peaks at 567 nm and 590 nm, respectively. Live-cell imaging revealed that Pink Flamindo is effective for monitoring the spatio-temporal dynamics of intracellular cAMP generated by photoactivated adenylyl cyclase in response to blue light, and in dual-colour imaging studies using a green Ca2+ indicator (G-GECO). Furthermore, we successfully monitored the elevation of cAMP levels in vivo in cerebral cortical astrocytes by two-photon imaging. We propose that Pink Flamindo will facilitate future in vivo, optogenetic studies of cell signalling and cAMP dynamics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Astrocytes / metabolism
  • Biosensing Techniques*
  • Calcium / metabolism
  • Cyclic AMP / chemistry
  • Cyclic AMP / metabolism*
  • Luminescent Proteins / chemistry
  • Luminescent Proteins / genetics*
  • Luminescent Proteins / metabolism*
  • Models, Molecular
  • Molecular Conformation
  • Molecular Imaging*
  • Optogenetics / methods*
  • Spectrophotometry
  • Structure-Activity Relationship

Substances

  • Luminescent Proteins
  • red fluorescent protein
  • Cyclic AMP
  • Calcium