Color vision: Studies on gecko cone visual pigment

Cone visual pigments are responsible for color vision. Although a large amount is known about rod pigments, relatively little is known about cone pigments. This thesis describes the identification and characterization of the photointermediates of gecko cone visual pigment P521: batho (ca. 570 nm), BSI (blue-shifted intermediate) (ca. 520 nm), lumi (ca. 516 nm) meta I (480 nm), and meta II (ca. 380 nm). The biologically active form of the rod visual pigment is its meta II intermediate, so special focus has been on the meta I to meta II transition of the gecko cone pigment. The formation of meta II does not have single exponential kinetics, but can be better characterized as having a fast and a slow component. High pH favors faster kinetics of meta II formation but with lower amounts. High temperature is found to favor a faster rate and larger amounts of meta II formation. The pK$\sb{\rm a}$ is 8.7 for the meta I $\rightleftharpoons$ meta II equilibrium, which is higher compared to that of the rod pigment (6.4) in comparable conditions. However, the fast component of the meta II formation is found to be different and has a somewhat lower pK$\sb{\rm a}$ (e.g. 6.4).

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biophysics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Liang, Jie

Contributors dc:contributor

• Ebrey, Thomas G.

• Health Sciences, Ophthalmology
• Biophysics, General

Statement dc:rights

• Copyright 1994 Liang, Jie

Language dc:language

eng

Identifier

AAI9512461
(UMI)AAI9512461

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/20413