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Structural biology of 11-cis-retinaldehyde production in the classical visual cycle.

ABSTRACT: The vitamin A derivative 11-cis-retinaldehyde plays a pivotal role in vertebrate vision by serving as the chromophore of rod and cone visual pigments. In the initial step of vision, a photon is absorbed by this chromophore resulting in its isomerization to an all-trans state and consequent activation of the visual pigment and phototransduction cascade. Spent chromophore is released from the pigments through hydrolysis. Subsequent photon detection requires the delivery of regenerated 11-cis-retinaldehyde to the visual pigment. This trans-cis conversion is achieved through a process known as the visual cycle. In this review, we will discuss the enzymes, binding proteins and transporters that enable the visual pigment renewal process with a focus on advances made during the past decade in our understanding of their structural biology.

SUBMITTER: Daruwalla A

PROVIDER: S-EPMC6440480 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Structural biology of 11-cis-retinaldehyde production in the classical visual cycle.

Daruwalla Anahita A Choi Elliot H EH Palczewski Krzysztof K Kiser Philip D PD

The Biochemical journal 20181022 20

The vitamin A derivative 11-cis-retinaldehyde plays a pivotal role in vertebrate vision by serving as the chromophore of rod and cone visual pigments. In the initial step of vision, a photon is absorbed by this chromophore resulting in its isomerization to an all-trans state and consequent activation of the visual pigment and phototransduction cascade. Spent chromophore is released from the pigments through hydrolysis. Subsequent photon detection requires the delivery of regenerate ...[more]

PMID: 30352831

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