[HTML][HTML] Signaling states of rhodopsin: Formation of the storage form, metarhodopsin III, from active metarhodopsin II

M Heck, SA Schädel, D Maretzki, FJ Bartl… - Journal of Biological …, 2003 - ASBMB
Vertebrate rhodopsin consists of the apoprotein opsin and the chromophore 11-cis-retinal
covalently linked via a protonated Schiff base. Upon photoisomerization of the chromophore
to all-trans-retinal, the retinylidene linkage hydrolyzes, and all-trans-retinal dissociates from
opsin. The pigment is eventually restored by recombining with enzymatically produced 11-
cis-retinal. All-trans-retinal release occurs in parallel with decay of the active form,
metarhodopsin (Meta) II, in which the original Schiff base is intact but deprotonated. The …