| Budget Amount *help |
¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000)
Fiscal Year 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2016: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
|
|---|
| Outline of Final Research Achievements |
The helix architecture of squid photo-activated metarhodopsin(Meta) is similar to that of the dark adapted form. The retinal chromophore is in an all-trans configuration with nearly same axial length to that of bovine Meta. The beta-ionone ring rotates ~ 60 degree to direct nearly parallel to the polyene chain plane. This rotation pushes surrounding aromatic rings of nearby residues to enlarge the binding pocket. These structural changes within the active site weaken the interhelical interactions at the cytoplasmic side. The salt bridge of the DRY motif between helices 3 and 6 is unlocked, resulting in being in partially open form in squid Meta.
The protonated Schiff base of retinal hydrogen bonds to the OH group of Tyr111 in helix 3, and Asn87 and Asn185 are located within 4A from the Schiff base. The counterion Glu180 is kept ~5A from the Schiff base by hydrogen bonds with Ser187, Tyr190, Tyr277 and Asn185. These residues form a hydrogen bonding network within the active site.
|
