Autofluorescent Proteins with Excitation in the Optical Window for Intravital Imaging in Mammals

Michael Z. Lin, Michael R. McKeown, Ho Leung Ng, Todd A. Aguilera, Nathan C. Shaner, Robert E. Campbell, Stephen R. Adams, Larry A. Gross, Wendy Ma, Tom Alber, Roger Y. Tsien

Research output: Contribution to journalArticle

175 Scopus citations

Abstract

Fluorescent proteins have become valuable tools for biomedical research as protein tags, reporters of gene expression, biosensor components, and cell lineage tracers. However, applications of fluorescent proteins for deep tissue imaging in whole mammals have been constrained by the opacity of tissues to excitation light below 600 nm, because of absorbance by hemoglobin. Fluorescent proteins that excite efficiently in the "optical window" above 600 nm are therefore highly desirable. We report here the evolution of far-red fluorescent proteins with peak excitation at 600 nm or above. The brightest one of these, Neptune, performs well in imaging deep tissues in living mice. The crystal structure of Neptune reveals a novel mechanism for red-shifting involving the acquisition of a new hydrogen bond with the acylimine region of the chromophore.

Original languageEnglish (US)
Pages (from-to)1169-1179
Number of pages11
JournalChemistry and Biology
Volume16
Issue number11
DOIs
StatePublished - Dec 21 2009

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Keywords

  • CELLBIO
  • CHEMBIO

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Medicine
  • Molecular Biology
  • Pharmacology
  • Drug Discovery
  • Clinical Biochemistry

Cite this

Lin, M. Z., McKeown, M. R., Ng, H. L., Aguilera, T. A., Shaner, N. C., Campbell, R. E., Adams, S. R., Gross, L. A., Ma, W., Alber, T., & Tsien, R. Y. (2009). Autofluorescent Proteins with Excitation in the Optical Window for Intravital Imaging in Mammals. Chemistry and Biology, 16(11), 1169-1179. https://doi.org/10.1016/j.chembiol.2009.10.009