Bright far-red fluorescent protein for whole-body imaging

Nat Methods. 2007 Sep;4(9):741-6. doi: 10.1038/nmeth1083. Epub 2007 Aug 26.


For deep imaging of animal tissues, the optical window favorable for light penetration is in near-infrared wavelengths, which requires proteins with emission spectra in the far-red wavelengths. Here we report a far-red fluorescent protein, named Katushka, which is seven- to tenfold brighter compared to the spectrally close HcRed or mPlum, and is characterized by fast maturation as well as a high pH-stability and photostability. These unique characteristics make Katushka the protein of choice for visualization in living tissues. We demonstrate superiority of Katushka for whole-body imaging by direct comparison with other red and far-red fluorescent proteins. We also describe a monomeric version of Katushka, named mKate, which is characterized by high brightness and photostability, and should be an excellent fluorescent label for protein tagging in the far-red part of the spectrum.

Publication types

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

MeSH terms

  • Animals
  • Biotechnology / instrumentation
  • Biotechnology / methods*
  • Embryo, Nonmammalian / cytology
  • Embryo, Nonmammalian / metabolism
  • Fluorescence Resonance Energy Transfer / instrumentation
  • Fluorescence Resonance Energy Transfer / methods*
  • Fluorescent Dyes* / analysis
  • Fluorescent Dyes* / chemistry
  • HeLa Cells
  • Humans
  • Luminescent Proteins* / analysis
  • Luminescent Proteins* / chemistry
  • Luminescent Proteins* / genetics
  • Microscopy, Confocal / instrumentation
  • Microscopy, Confocal / methods*
  • Microscopy, Fluorescence / instrumentation
  • Microscopy, Fluorescence / methods*
  • Transgenes
  • Xenopus laevis


  • Fluorescent Dyes
  • Luminescent Proteins
  • red fluorescent protein