8TKP

Structure of the C. elegans TMC-2 complex

Summary for 8TKP

• Entry DOI: 10.2210/pdb8tkp/pdb
• EMDB information: 41356 41432
• Descriptor: Transmembrane channel-like protein 2, 2-acetamido-2-deoxy-beta-D-glucopyranose, CALCIUM ION, ... (12 entities in total)
• Functional Keywords: mechanosensory transduction macromolecular complex, membrane protein
• Biological source: Caenorhabditis elegans; More
• Total number of polymer chains: 6
• Total formula weight: 362476.16

Authors

Clark, S.,Jeong, H.,Goehring, A.,Posert, R.,Gouaux, E. (deposition date: 2023-07-25, release date: 2024-03-27)

Primary citation

Clark, S.,Jeong, H.,Posert, R.,Goehring, A.,Gouaux, E.
The structure of the Caenorhabditis elegans TMC-2 complex suggests roles of lipid-mediated subunit contacts in mechanosensory transduction.
Proc.Natl.Acad.Sci.USA, 121:e2314096121-e2314096121, 2024

PubMed Abstract: Mechanotransduction is the process by which a mechanical force, such as touch, is converted into an electrical signal. Transmembrane channel-like (TMC) proteins are an evolutionarily conserved family of membrane proteins whose function has been linked to a variety of mechanosensory processes, including hearing and balance sensation in vertebrates and locomotion in . TMC1 and TMC2 are components of ion channel complexes, but the molecular features that tune these complexes to diverse mechanical stimuli are unknown. express two TMC homologs, TMC-1 and TMC-2, both of which are the likely pore-forming subunits of mechanosensitive ion channels but differ in their expression pattern and functional role in the worm. Here, we present the single-particle cryo-electron microscopy structure of the native TMC-2 complex isolated from . The complex is composed of two copies of the pore-forming TMC-2 subunit, the calcium and integrin binding protein CALM-1 and the transmembrane inner ear protein TMIE. Comparison of the TMC-2 complex to the recently published cryo-EM structure of the TMC-1 complex highlights conserved protein-lipid interactions, as well as a π-helical structural motif in the pore-forming helices, that together suggest a mechanism for TMC-mediated mechanosensory transduction.

PubMed: 38354260
DOI: 10.1073/pnas.2314096121

Experimental method

ELECTRON MICROSCOPY (2.9 Å)