On the mechanism of photoinduced dimer dissociation in the plant UVR8 photoreceptor.

ABSTRACT: UV-B absorption by the photoreceptor UV resistance locus 8 (UVR8) consisting of two identical protein units triggers a signal chain used by plants in connection with protection and repair of UV-B induced damage. X-ray structural analysis of the purified protein [Christie JM, et al. (2012) Science 335(6075):1492-1496] [Wu D, et al. (2012) Nature 484(7393): 214-220] has revealed that the dimer is held together by arginine-aspartate salt bridges. In this paper we address the initial processes in the signal chain. On the basis of high-level quantum-chemical calculations, we propose a mechanism for the photodissociation of UVR8 that consists of three steps: (i) In each monomer, multiple tryptophans form an extended light-harvesting system in which the La excited state of Trp233 experiences stro

SUBMITTER: Voityuk AA 

PROVIDER: S-EPMC3986182 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature