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How Does Photoreceptor UVR8 Perceive a UV-B Signal?

ABSTRACT: UVR8 is the only known plant photoreceptor that mediates light responses to UV-B (280-315 nm) of the solar spectrum. UVR8 perceives a UV-B signal via light-induced dimer dissociation, which triggers a wide range of cellular responses involved in photomorphogenesis and photoprotection. Two recent crystal structures of Arabidopsis thaliana UVR8 (AtUVR8) have revealed unusual clustering of UV-B-absorbing Trp pigments at the dimer interface and provided a structural framework for further mechanistic investigation. This review summarizes recent advances in spectroscopic, computational and crystallographic studies on UVR8 that are directed toward full understanding of UV-B perception at the molecular level.

SUBMITTER: Yang X

PROVIDER: S-EPMC4560659 | biostudies-literature | 2015 Sep-Oct

REPOSITORIES: biostudies-literature

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How Does Photoreceptor UVR8 Perceive a UV-B Signal?

Yang Xiaojing X Montano Sherwin S Ren Zhong Z

Photochemistry and photobiology 20150611 5

UVR8 is the only known plant photoreceptor that mediates light responses to UV-B (280-315 nm) of the solar spectrum. UVR8 perceives a UV-B signal via light-induced dimer dissociation, which triggers a wide range of cellular responses involved in photomorphogenesis and photoprotection. Two recent crystal structures of Arabidopsis thaliana UVR8 (AtUVR8) have revealed unusual clustering of UV-B-absorbing Trp pigments at the dimer interface and provided a structural framework for further mechanistic ...[more]

PMID: 25996910

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