German scientists Peter Hegemann and Georg Nagel have received the 2026 Nobel Prize in Physiology or Medicine for the discovery of light-sensitive ion channels, work that paved the way for optogenetics. The Max Planck Society, where both led research groups, congratulated the two laureates, regarded as the founders of the field.
The so-called channelrhodopsins are membrane proteins found in the single-celled green alga Chlamydomonas reinhardtii, which uses them to orient itself towards light. When stimulated by light, they let positively charged ions through, acting as switches that control the flow of information in nerve cells.
Through gene transfer, these proteins can be placed in the membranes of animal neurons. Because other similar proteins let negative ions through, scientists can activate or inhibit nerve cells using light alone.
Hegemann led a group at the Max Planck Institute of Biochemistry in Martinsried between 1986 and 1993, and has been at Humboldt University of Berlin since 2005. Nagel headed a group at the Max Planck Institute of Biophysics in Frankfurt between 1992 and 2004, and has been a professor at the University of Würzburg since then. Applications under development include optogenetic cochlear implants and vision aids for retinal damage.
