Structure of the thermo-sensitive TRP channel TRP1 from the alga Chlamydomonas reinhardtii

Algae produce the largest amount of oxygen on earth and are invaluable for human nutrition and biomedicine, as well as for the chemical industry, energy production and agriculture. The mechanisms by which algae can detect and respond to changes in their environments can rely on membrane receptors, including TRP ion channels. Here we present a 3.5-Å resolution cryo-EM structure of the transient receptor potential (TRP) channel crTRP1 from the alga Chlamydomonas reinhardtii that opens in response to increased temperature and is positively regulated by the membrane lipid PIP 2 . The structure of crTRP1 significantly deviates from the structures of other TRP channels and has a unique 2-fold symmetrical rose-shape architecture with elbow domains and ankyrin repeat domains submerged and dipping into the membrane, respectively. Our study provides a structure of a TRP channel from a micro-organism and a structural framework for better understanding algae biology and TRP channel evolution. Transient receptor potential (TRP) channels are ubiquitous occurring cation-selective sensory ion channels that respond to various stimuli. Here the authors characterize crTRP1 from the alga Chlamydomonas reinhardtii , present its 3.5 Å cryo-EM structure and show that crTRP1 opens in response to increased temperature and is positively regulated by the membrane lipid PIP 2 .