Ligand-binding domain subregions contributing to bimodal agonism in cyclic nucleotide–gated channels
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چکیده
منابع مشابه
Ligand-binding domain subregions contributing to bimodal agonism in cyclic nucleotide–gated channels
Cyclic nucleotide-gated (CNG) channels bind cGMP or cAMP in a cytoplasmic ligand-binding domain (BD), and this binding typically increases channel open probability (P(o)) without inducing desensitization. However, the catfish CNGA2 (fCNGA2) subtype exhibits bimodal agonism, whereby steady-state P(o) increases with initial cGMP-binding events ("pro" action) up to a maximum of 0.4, but decreases ...
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Cyclic nucleotide-gated channels are composed of a core transmembrane domain, structurally homologous to the voltage-gated K+ channels, and a cytoplasmic ligand-binding domain. These two modules are joined by approximately 90 conserved amino acids, the C-linker, whose precise role in the mechanism of channel activation by cyclic nucleotides is poorly understood. We examined cyclic nucleotide-ga...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 2011
ISSN: 1540-7748,0022-1295
DOI: 10.1085/jgp.201010560