Skip to main content
Log in

The DC gate in Channelrhodopsin-2: crucial hydrogen bonding interaction between C128 and D156

  • Paper
  • Published:
Photochemical & Photobiological Sciences Aims and scope Submit manuscript

Abstract

The light-gated cation channel Channelrhodopsin-2 (ChR2), a retinylideneprotein found in the eye-spot of Chlamydomonas reinhardtii, became an optogenetic tool to trigger neurophysiological responses by light and, thus, revolutionized spatio-temporal studies of such processes. The reaction mechanism still remains elusive but recent vibrational spectroscopic experiments started to resolve details of the associated structural changes during the photocycle. Large alterations in the polypeptide backbone were observed by FT-IR spectroscopy that precede and succeed the opening and closing of the channel, respectively. However, the molecular switch that controls gating is still unknown. Here, we present difference spectra of the D156E mutant of ChR2 and assign the observed vibrational bands to crucial hydrogen bonding changes of this residue in various intermediate states of the photoreaction. By comparison with spectra of wild-type ChR2 and the C128T mutant and correlation to electrophysiological studies, we propose the DC gate as a crucial hydrogen-bonding interaction between D156 and C128 which may represent the valve of the channel.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Notes and references

  1. K. W. Foster, J. Saranak, N. Patel, G. Zarilli, M. Okabe, T. Kline and K. Nakanishi, A rhodopsin is the functional photoreceptor for phototaxis in the unicellular eukaryote Chlamydomonas, Nature, 1984, 311, 756.

    Article  CAS  Google Scholar 

  2. G. Nagel, T. Szellas, W. Huhn, S. Kateriya, N. Adeishvili, P. Berthold, D. Ollig, P. Hegemann and E. Bamberg, Channelrhodopsin-2, a directly light-gated cation-selective membrane channel, Proc. Natl. Acad. Sci. U. S. A., 2003, 100, 13940.

    Article  CAS  Google Scholar 

  3. O. A. Sineshchekov, K. H. Jung and J. L. Spudich, Two rhodopsins mediate phototaxis to low- and high-intensity light in Chlamydomonas reinhardtii, Proc. Natl. Acad. Sci. U. S. A., 2002, 99, 8689.

    Article  CAS  Google Scholar 

  4. R. H. Kramer, D. L. Fortin and D. Trauner, New photochemical tools for controlling neuronal activity, Curr. Opin. Neurobiol., 2009, 19, 544.

    Article  CAS  Google Scholar 

  5. O. P. Ernst, P. A. Sanchez Murcia, P. Daldrop, S. P. Tsunoda, S. Kateriya and P. Hegemann, Photoactivation of channelrhodopsin, J. Biol. Chem., 2008, 283, 1637.

    Article  CAS  Google Scholar 

  6. C. Bamann, T. Kirsch, G. Nagel and E. Bamberg, Spectral characteristics of the photocycle of channelrhodopsin-2 and its implication for channel function, J. Mol. Biol., 2008, 375, 686.

    Article  CAS  Google Scholar 

  7. I. Radu, C. Bamann, M. Nack, G. Nagel, E. Bamberg and J. Heberle, Conformational changes of channelrhodopsin-2, J. Am. Chem. Soc., 2009, 131, 7313.

    Article  CAS  Google Scholar 

  8. E. Ritter, K. Stehfest, A. Berndt, P. Hegemann and F. J. Bartl, Monitoring light-induced structural changes of Channelrhodopsin-2 by UV-visible and Fourier transform infrared spectroscopy, J. Biol. Chem., 2008, 283, 35033.

    Article  CAS  Google Scholar 

  9. C. Kötting and K. Gerwert, Proteins in action monitored by time-resolved FTIR spectroscopy, ChemPhysChem, 2005, 6, 881.

    Article  Google Scholar 

  10. I. Radu, M. Schleeger, C. Bolwien and J. Heberle, Time-Resolved FT-IR Difference Spectroscopy and the Application to Membrane Proteins, Photochem. Photobiol. Sci., 2009, 8, 1517.

    Article  CAS  Google Scholar 

  11. W. Mäntele, Reaction-induced infrared difference spectroscopy for the study of protein function and reaction mechanisms, Trends Biochem. Sci., 1993, 18, 197.

    Article  Google Scholar 

  12. A. Maeda, Application of FTIR spectroscopy to the structural study on the function of bacteriorhodopsin, Isr. J. Chem., 1995, 35, 387.

    Article  CAS  Google Scholar 

  13. K. Edman, A. Royant, P. Nollert, C. A. Maxwell, E. Pebay-Peyroula, J. Navarro, R. Neutze and E. M. Landau, Early structural rearrangements in the photocycle of an integral membrane sensory receptor, Structure, 2002, 10, 473.

    Article  CAS  Google Scholar 

  14. A. Barth, The infrared absorption of amino acid side chains, Prog. Biophys. Mol. Biol., 2000, 74, 141.

    Article  CAS  Google Scholar 

  15. C. Bamann, R. Gueta, S. Kleinlogel, G. Nagel and E. Bamberg, Structural Guidance of the Photocycle of Channelrhodopsin-2 by an Interhelical Hydrogen Bond, Biochemistry, 2009 DOI: 10.1021/bi901634p.

    Google Scholar 

  16. G. Nagel, T. Szellas, S. Kateriya, N. Adeishvili, P. Hegemann and E. Bamberg, Channelrhodopsins: directly light-gated cation channels, Biochem. Soc. Trans., 2005, 33, 863.

    Article  CAS  Google Scholar 

  17. M. Nack, I. Radu, C. Bamann, E. Bamberg and J. Heberle, The retinal structure of channelrhodopsin-2 assessed by resonance Raman spectroscopy, FEBS Lett., 2009, 583, 3676.

    Article  CAS  Google Scholar 

  18. B. Nie, J. Stutzman and A. Xie, A vibrational spectral maker for probing the hydrogen-bonding status of protonated Asp and Glu residues, Biophys. J., 2005, 88, 2833.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Joachim Heberle.

Additional information

This paper is part of a themed issue on synthetic and natural photoswitches.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Nack, M., Radu, I., Gossing, M. et al. The DC gate in Channelrhodopsin-2: crucial hydrogen bonding interaction between C128 and D156. Photochem Photobiol Sci 9, 194–198 (2010). https://doi.org/10.1039/b9pp00157c

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1039/b9pp00157c

Navigation