1.A.84.1.4
Calcium homeostasis modulator 1 (CALHM1 or FAM26C) is the pore-forming subunit of an ion channel that mediates extracellular Ca²⁺ regulation of neuronal excitability (Ma et al. 2015). CALHM1 (CALHM-1 or CLHM-1) is of 329 aas and exhibits 4 or 5 TMSs. This protein forms a protein complex, 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. 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. Yang et al. 2020 and Demura et al. 2020 presented the structure of the Caenorhabditis elegans CLHM1 channel (1.A.84.1.4) in its open state, solved through single-particle cryo-EM at 3.7Å resolution. The transmembrane region of the channel structure of the dominant class shows an assembly of tenfold rotational symmetry in one layer, and its cytoplasmic region is involved in additional twofold symmetrical packing in a tail-to-tail manner. A series of amino acyl residues are critical for the regulation of the channel. presented the structure of the channel in its open state, solved through single-particle cryo-EM at 3.7Å resolution. The transmembrane region of the channel shows an assembly of tenfold rotational symmetry in one layer, and its cytoplasmic region is involved in additional twofold symmetrical packing in a tail-to-tail manner. A series of amino acyl residues are critical for regulation of the channel (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. Yang et al. 2020 presented the structure of the Caenorhabditis elegans CLHM1 channel (1.A.84.1.4) in its open state, solved through single-particle cryo-EM at 3.7Å resolution. The transmembrane region of the channel structure of the dominant class shows an assembly of tenfold rotational symmetry in one layer, and its cytoplasmic region is involved in additional twofold symmetrical packing in a tail-to-tail manner. A series of amino acyl residues are critical for regulation of the channel (Yang et al. 2020).