Light triggered activation of the G-protein coupled photoreceptor rhodopsin: A structural and functional description
2000 (English)In: Recent research developments in bioenergetics, Vol. 1, 103-15 p.Article in journal (Refereed) Published
Rhodopsin, a 39 kDa photoreceptor is responsible for converting an incident photon of visible light into an optic nerve impulse. The protein belongs to the family of G-protein coupled receptors, which transduce chemical or optical signals across a cellular membrane. The ability of rhodopsin to convert light energy into a neuronal response is the result of isomerization of its chromophore retinal during the early primary photochemical events leading to activation of the protein. This activation is initiated by the photoisomerization of 11-cis retinal which is covalently attached to Lys-296 as a protonated Schiff base and gets slowly released from the protein as all-trans retinal. In order to understand the mechanism of conversion of light energy via this receptor protein into a final neuronal impulse, a precise elucidation of the structural organization of the chromophore binding site in the photoreceptor and its interaction with the chromophore after visual excitation is essential. Recently, various solid state NMR studies using nonperturbing spin reporters have provided an atomic level description of the overall orientation and structure of the chromophore within the binding pocket for various stages of the photoactivation, well ahead of any crystallographic efforts.
Place, publisher, year, edition, pages
2000. Vol. 1, 103-15 p.
IdentifiersURN: urn:nbn:se:umu:diva-8635OAI: oai:DiVA.org:umu-8635DiVA: diva2:148306
ISBN 81-86846-59-X2008-02-012008-02-012011-01-14Bibliographically approved