The SFB members Jonas Wietek, Franziska Schneider, and Prof. Peter Hegemann from project B2 and co-workers have published their article "Conversion of Channelrhodopsin into a Light-Gated Chloride Channel" in Science magazine (1). The article is also covered in the comment by Shigehiko Hayashi with the title "Silencing Neurons with Light" (2). Congratulations!!!

In their report, Wietek et al. describe how they used structure-based molecular engineering to invert the charge selectivity of the light-gated ion channel, channelrhodopsin. Native channelrhodopsin conducts cations across the membrane. In contrast, the channelrhodopsin engineered by Wietek et al. selectively conducts chloride ions. The conversion of ion selectivity was achieved by a single mutation in the central gate of the ion channel. In optogenetics applications, that new class of directly light-gated anion channels can be used to silence neurons in a fully reversible fashion.

References:

1. Wietek, J., Wiegert, J.S., Adeishvili, N., Schneider, F., Watanabe, H., Tsunoda, S.P., Vogt, A., Elstner, M., Oertner, T.G., and Hegemann, P. (2014). Conversion of channelrhodopsin into a light-gated chloride channel. Science 344, 409-412 (doi: 10.1126/science.1249375).
2. Hayashi, S. (2014) Silencing neurons with light. Science 344, 369-370 (doi: 10.1126/science.1253616).