@entity1921 -gated (CNG) channels are crucial for sensory transduction in the photoreceptors (rods and cones) of the vertebrate retina. Light triggers a decrease in the cytoplasmic concentration of @entity8262 in the outer segments of these cells, leading to closure of CNG channels and hyperpolarization of the membrane potential. Hence, CNG channels translate a chemical change in cyclic @entity377 concentration into an electrical signal that can spread through the photoreceptor cell and be transmitted to the rest of the visual system. The sensitivity of phototransduction can be altered by exposing the cells to light, through adaptation processes intrinsic to photoreceptors. Intracellular @entity141 is a major signal in light adaptation and, in conjunction with @entity141 -binding proteins, one of its targets for modulation is the CNG channel itself. However, other intracellular signals may be involved in the fine-tuning of light sensitivity in response to cues internal to organisms. Several intracellular signals are candidates for mediating changes in @entity8262 sensitivity including @entity9546 , such as @entity3411 and @entity8862 , and lipid metabolites, such as @entity2366 . Moreover, CNG channels are associated with protein kinases and phosphatases that catalyze changes in phosphorylation state and allosterically modulate channel activity. Recent studies suggest that the effects of circadian rhythms and retinal transmitters on CNG channels may be mediated by such changes in phosphorylation. The goal of this paper is to review the molecular mechanisms underlying modulation of CNG channels and to relate these forms of modulation to the regulation of light sensitivity.

Modulation of cyclic- XXXX -gated channels and regulation of vertebrate phototransduction.

@entity8862 :: ('CHEBI:37256', 'Chemical') :: ['Zn(2+)'] @entity2366 :: ('CHEBI:41847', 'Chemical') :: ['diacylglycerol'] @entity377 :: ('CHEBI:36976', 'Chemical') :: ['nucleotide'] @entity1921 :: ('CHEBI:23447', 'Chemical') :: ['Cyclic-nucleotide'] @entity8262 :: ('MESH:D006152', 'Chemical') :: ['cyclic GMP'] @entity3411 :: ('CHEBI:49786', 'Chemical') :: ['Ni(2+)'] @entity141 :: ('CHEBI:29108', 'Chemical') :: ['Ca(2+)'] @entity9546 :: ('CHEBI:27081', 'Chemical') :: ['transition metals']
@entity377 :: (CHEBI:36976,Chemical) :: ['nucleotide']
