Cellular Mechanisms of Cone Defects in Cyclic Nucleotide-Gated Channel Deficiency
Pp. 109-124 (16)
Xi-Qin Ding, Hongwei Ma, Martin Biel and Stylianos Michalakis
The cone photoreceptor-specific cyclic nucleotide-gated (CNG) channel is
indispensable for cone function. Cones are essential for daylight vision and visual
acuity. Mutations in the CNGA3 and CNGB3 genes are associated with achromatopsia,
cone degeneration, and early-onset macular degeneration, and account for 80-85% of
Achromatopsia cases. Patients with CNG channel defects exhibit cone dysfunction and
progressive degeneration of cones, as revealed by electrophysiological recordings,
psychophysical testing, and morphological examinations. The cellular events and
underlying mechanisms of CNG channel deficiency have been explored using mouse
models. In this review, we have summarized our current understanding of the modes of
cone defects due to CNG channel deficiency.
Apoptosis, cGMP, CNG channel, Cone, Endoplasmic reticulum,
Mitochondrion, Photoreceptor, PKG, Retina.
Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA