Retinal Flip in Rhodopsin Activation?
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ABSTRACT:
SUBMITTER: Feng J
PROVIDER: S-EPMC4472225 | biostudies-literature | 2015 Jun
REPOSITORIES: biostudies-literature
Publications
Retinal Flip in Rhodopsin Activation?
Feng Jun J Brown Michael F MF Mertz Blake B
Biophysical journal 20150601 12
Rhodopsin is a well-characterized structural model of a G protein-coupled receptor. Photoisomerization of the covalently bound retinal triggers activation. Surprisingly, the x-ray crystal structure of the active Meta-II state has a 180° rotation about the long-axis of the retinal polyene chain. Unbiased microsecond-timescale all-atom molecular dynamics simulations show that the retinal cofactor can flip back to the orientation observed in the inactive state of rhodopsin under conditions favoring ...[more]
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