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Light-induced structural changes of the LOV2 domains in various phototropins revealed by FTIR spectroscopy.

ABSTRACT: Phototropin (Phot), a blue-light photoreceptor in plants, consists of two FMN-binding domains (named LOV1 and LOV2) and a serine/threonine (Ser/Thr) kinase domain. We have investigated light-induced structural changes of LOV domains, which lead to the activation of the kinase domain, by means of light-induced difference FTIR spectroscopy. FTIR spectroscopy revealed that the reactive cysteine is protonated in both unphotolyzed and triplet-excited states, which is difficult to detect by other methods such as X-ray crystallography. In this review, we describe the light-induced structural changes of hydrogen-bonding environment of FMN chromophore and protein backbone in Adiantum neo1-LOV2 in the C=O stretching region by use of 13C-labeled samples. We also describe the comprehensive FTIR analysis of LOV2 domains among Arabidopsis phot1, phot2, and Adiantum neo1 with and without J? helix domain.

SUBMITTER: Iwata T

PROVIDER: S-EPMC5036776 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Light-induced structural changes of the LOV2 domains in various phototropins revealed by FTIR spectroscopy.

Iwata Tatsuya T Tokutomi Satoru S Kandori Hideki H

Biophysics (Nagoya-shi, Japan) 20111109

Phototropin (Phot), a blue-light photoreceptor in plants, consists of two FMN-binding domains (named LOV1 and LOV2) and a serine/threonine (Ser/Thr) kinase domain. We have investigated light-induced structural changes of LOV domains, which lead to the activation of the kinase domain, by means of light-induced difference FTIR spectroscopy. FTIR spectroscopy revealed that the reactive cysteine is protonated in both unphotolyzed and triplet-excited states, which is difficult to detect by other meth ...[more]

PMID: 27857596

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