Sandbox Reserved 895: Difference between revisions

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Following dissociation from opsin, all-''trans''-retinal is transported from the lumen of the photoreceptor disk though an ATP-cassette transporter 4 (''ABCA4''). The enzyme all-''trans''-retinol dehydrogenase (atRDH) reduces all-''trans''-retinal into all-''trans''-retinol. Another transporter enzyme, interphotoreceptor retinoid-binding protein (IRBP) facilitates the transporter of all-''trans''-retinol back into the hRPE. Within the hRPE, all-''trans''-retinol is esterified by the enzyme lecithin retinol acyltransferase (LRAT) to form all-''trans''-retinyl ester. RPE65 also known as retinoid isomerohydrolase (IMH) then converts all-''trans''-retinyl ester into 11-''cis''-retinol and palmityl acid. Following the RPE65 catalyzed reaction, 11-''cis''-retinol dehydrogenase (11-''cis''-RDH) oxidizes 11-''cis''-retinol into 11-''cis''-retinal. 11-''cis''-retinal is finally transported back into the photoreceptors to be conjugated to opsin to form the rhodopsin complex. This process is shown in Figure 2. <ref>DOI 10.1016/j.bbadis.2018.04.014</ref>

[[Image:~~Visual Cycle~~.jpg|thumb|center|512 px|alt=Figure 2: Human Visual Cycle| '''Figure 2:''' A schematic representation of the Retinoid (Visual) Cycle in Humans. (Abbreviations: all-''trans''-ROL, all-''trans''-retinol; LRAT, lecithin retinol acyltransferase; RPE65, retinal pigment epithelium 65; 11-''cis''-ROL, 11-''cis''-retinol; 11-''cis''-RDH, 11-''cis''-retinol dehydrogenase; 11-''ci''s-RAL, 11-''cis''-retinal; ''hV'', light energy; all-''trans''-RAL, all-''trans''-retinal; atRDH, all-''trans''-retinol dehydrogenase) <ref> DOI 10.1016/j.bbadis.2018.04.014 </ref>]]

[[Image:Visual_Cycle.jpg|thumb|center|512 px|alt=Figure 2: Human Visual Cycle| '''Figure 2:''' A schematic representation of the Retinoid (Visual) Cycle in Humans. (Abbreviations: all-''trans''-ROL, all-''trans''-retinol; LRAT, lecithin retinol acyltransferase; RPE65, retinal pigment epithelium 65; 11-''cis''-ROL, 11-''cis''-retinol; 11-''cis''-RDH, 11-''cis''-retinol dehydrogenase; 11-''ci''s-RAL, 11-''cis''-retinal; ''hV'', light energy; all-''trans''-RAL, all-''trans''-retinal; atRDH, all-''trans''-retinol dehydrogenase) <ref> DOI 10.1016/j.bbadis.2018.04.014 </ref>]]

== '''[1.2] RPE65''' ==

Sandbox Reserved 895: Difference between revisions

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 Following dissociation from opsin, all-''trans''-retinal is transported from the lumen of the photoreceptor disk though an ATP-cassette transporter 4 (''ABCA4''). The enzyme all-''trans''-retinol dehydrogenase (atRDH) reduces all-''trans''-retinal into all-''trans''-retinol. Another transporter enzyme, interphotoreceptor retinoid-binding protein (IRBP) facilitates the transporter of all-''trans''-retinol back into the hRPE. Within the hRPE, all-''trans''-retinol is esterified by the enzyme lecithin retinol acyltransferase (LRAT) to form all-''trans''-retinyl ester. RPE65 also known as retinoid isomerohydrolase (IMH) then converts all-''trans''-retinyl ester into 11-''cis''-retinol and palmityl acid. Following the RPE65 catalyzed reaction, 11-''cis''-retinol dehydrogenase (11-''cis''-RDH) oxidizes 11-''cis''-retinol into 11-''cis''-retinal. 11-''cis''-retinal is finally transported back into the photoreceptors to be conjugated to opsin to form the rhodopsin complex. This process is shown in Figure 2. <ref>DOI 10.1016/j.bbadis.2018.04.014</ref>
-[[Image:Visual Cycle.jpg|thumb|center|512 px|alt=Figure 2: Human Visual Cycle| '''Figure 2:''' A schematic representation of the Retinoid (Visual) Cycle in Humans. (Abbreviations: all-''trans''-ROL, all-''trans''-retinol; LRAT, lecithin retinol acyltransferase; RPE65, retinal pigment epithelium 65; 11-''cis''-ROL, 11-''cis''-retinol; 11-''cis''-RDH, 11-''cis''-retinol dehydrogenase; 11-''ci''s-RAL, 11-''cis''-retinal; ''hV'', light energy; all-''trans''-RAL, all-''trans''-retinal; atRDH, all-''trans''-retinol dehydrogenase) <ref> DOI 10.1016/j.bbadis.2018.04.014 </ref>]]
+[[Image:Visual_Cycle.jpg|thumb|center|512 px|alt=Figure 2: Human Visual Cycle| '''Figure 2:''' A schematic representation of the Retinoid (Visual) Cycle in Humans. (Abbreviations: all-''trans''-ROL, all-''trans''-retinol; LRAT, lecithin retinol acyltransferase; RPE65, retinal pigment epithelium 65; 11-''cis''-ROL, 11-''cis''-retinol; 11-''cis''-RDH, 11-''cis''-retinol dehydrogenase; 11-''ci''s-RAL, 11-''cis''-retinal; ''hV'', light energy; all-''trans''-RAL, all-''trans''-retinal; atRDH, all-''trans''-retinol dehydrogenase) <ref> DOI 10.1016/j.bbadis.2018.04.014 </ref>]]
 == '''[1.2] RPE65''' ==