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Review
. 2015 Nov 15;128(22):4039-45.
doi: 10.1242/jcs.175687.

Photoreceptors at a glance

Robert S Molday  1 , Orson L Moritz  2
Affiliations
Review

Photoreceptors at a glance

Robert S Molday et al. J Cell Sci. .

Abstract

Retinal photoreceptor cells contain a specialized outer segment (OS) compartment that functions in the capture of light and its conversion into electrical signals in a process known as phototransduction. In rods, photoisomerization of 11-cis to all-trans retinal within rhodopsin triggers a biochemical cascade culminating in the closure of cGMP-gated channels and hyperpolarization of the cell. Biochemical reactions return the cell to its 'dark state' and the visual cycle converts all-trans retinal back to 11-cis retinal for rhodopsin regeneration. OS are continuously renewed, with aged membrane removed at the distal end by phagocytosis and new membrane added at the proximal end through OS disk morphogenesis linked to protein trafficking. The molecular basis for disk morphogenesis remains to be defined in detail although several models have been proposed, and molecular mechanisms underlying protein trafficking are under active investigation. The aim of this Cell Science at a Glance article and the accompanying poster is to highlight our current understanding of photoreceptor structure, phototransduction, the visual cycle, OS renewal, protein trafficking and retinal degenerative diseases.

Keywords: Disk morphogenesis; Photoreceptors; Phototransduction; Protein trafficking; Retinal degenerative diseases; Visual cycle.

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Conflict of interest statement

Competing interests

The authors declare no competing or financial interests.

References

    1. Agbaga M.-P., Tam B. M., Wong J. S., Yang L. L., Anderson R. E. and Moritz O. L. (2014). Mutant ELOVL4 that causes autosomal dominant stargardt-3 macular dystrophy is misrouted to rod outer segment disks. Invest. Ophthalmol. Vis. Sci. 55, 3669-3680. 10.1167/iovs.13-13099 - DOI - PMC - PubMed
    1. Allikmets R., Singh N., Sun H., Shroyer N. F., Hutchinson A., Chidambaram A., Gerrard B., Baird L., Stauffer D., Peiffer A. et al. (1997). A photoreceptor cell-specific ATP-binding transporter gene (ABCR) is mutated in recessive Starqardt macular dystrophy. Nat. Genet. 15, 236-246. 10.1038/ng0397-236 - DOI - PubMed
    1. Anderson D. H., Fisher S. K. and Steinberg R. H. (1978). Mammalian cones: disc shedding, phagocytosis, and renewal. Invest. Ophthalmol. Vis. Sci. 17, 117-133. - PubMed
    1. Arikawa K., Molday L. L., Molday R. S. and Williams D. S. (1992). Localization of peripherin/rds in the disk membranes of cone and rod photoreceptors: relationship to disk membrane morphogenesis and retinal degeneration. J. Cell Biol. 116, 659-667. 10.1083/jcb.116.3.659 - DOI - PMC - PubMed
    1. Arshavsky V. Y. and Burns M. E. (2012). Photoreceptor signaling: supporting vision across a wide range of light intensities. J. Biol. Chem. 287, 1620-1626. 10.1074/jbc.R111.305243 - DOI - PMC - PubMed

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