Imaging neuronal activity with genetically encoded calcium indicators

Cold Spring Harb Protoc. 2012 Jun 1;2012(6):647-56. doi: 10.1101/pdb.top069609.


Genetically encoded calcium indicators (GECIs), which are based on chimeric fluorescent proteins, can be used to monitor calcium transients in living cells and organisms. Because they are encoded by DNA, GECIs can be delivered to the intact brain noninvasively and targeted to defined populations of neurons and specific subcellular compartments for long-term, repeated measurements in vivo. GECIs have improved iteratively and are becoming useful for imaging neural activity in vivo. Here we summarize extrinsic and intrinsic factors that influence a GECI's performance and provides guidelines for selecting the appropriate GECI for a given application. We also review recent progress in GECI design, optimization, and standardized testing protocols.

Publication types

  • Review

MeSH terms

  • Calcium / analysis*
  • Genes, Reporter
  • Image Processing, Computer-Assisted / methods*
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Microscopy, Fluorescence / methods*
  • Neurons / chemistry
  • Neurons / physiology*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism


  • Luminescent Proteins
  • Recombinant Proteins
  • Calcium