Molecule of the Month: Capsaicin Receptor TRPV1
TRPV1 is an ion channel that senses heat and contributes to pain sensation.
CryoEM and Nanodiscs
Exploring the Structure
Closed and Open TRPV1
Cryoelectron microscopy has allowed researchers to capture TRP channels in many different states. PDB entry 5irz is the closed TRPV1 channel, with several rings of amino acids forming constrictions that block the ion pore. In 5irx, the channel is held open by the binding of two toxins (shown in purple and magenta), shifting the location of these amino acids to open the ion conducting pathway. To explore these structures in more detail, click on the image for an interactive JSmol.
Topics for Further Discussion
- Structures for many TRP channels are available in the PDB archive, try searching for "TRP channel" at the main RCSB PDB site to explore them.
- Many other ion channels are composed of a ring of subunits or domains. Compare the structure of the TRP channel with, for example, Piezo1 channels, potassium channels, and mechanosensitive channels.
October 2020, David Goodsellhttp://doi.org/10.2210/rcsb_pdb/mom_2020_10