Cryo-electron microscopy structure of CLHM1 ion channel from Caenorhabditis elegans.
Protein Sci
; 29(8): 1803-1815, 2020 08.
Article
in En
| MEDLINE
| ID: mdl-32557855
ABSTRACT
Calcium homeostasis modulators (CALHMs/CLHMs) comprise a family of pore-forming protein complexes assembling into voltage-gated, Ca2+ -sensitive, nonselective channels. These complexes contain an ion-conduction pore sufficiently wide to permit the passing of ATP molecules serving as neurotransmitters. While their function and structure information is accumulating, the precise mechanisms of these channel complexes remain to be full understood. Here, we present the structure of the Caenorhabditis elegans CLHM1 channel in its open state solved through single-particle cryo-electron microscopy at 3.7-Å resolution. The transmembrane region of the channel structure of the dominant class shows an assembly of 10-fold rotational symmetry in one layer, and its cytoplasmic region is involved in additional twofold symmetrical packing in a tail-to-tail manner. Furthermore, we identified a series of amino acid residues critical for the regulation of CeCLHM1 channel using functional assays, electrophysiological analyses as well as structural-based analysis. Our structure and function analyses provide new insights into the mechanisms of CALHM channels.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Calcium Channels
/
Protein Folding
/
Caenorhabditis elegans
/
Caenorhabditis elegans Proteins
Limits:
Animals
Language:
En
Journal:
Protein Sci
Journal subject:
BIOQUIMICA
Year:
2020
Document type:
Article
Affiliation country: