A critical element of the light-induced quaternary structural changes in YtvA-LOV.

ABSTRACT: YtvA, a photosensory LOV (light-oxygen-voltage) protein from Bacillus subtilis, exists as a dimer that previously appeared to undergo surprisingly small structural changes after light illumination compared with other light-sensing proteins. However, we now report that light induces significant structural perturbations in a series of YtvA-LOV domain derivatives in which the J? helix has been truncated or replaced. Results from native gel analysis showed significant mobility changes in these derivatives after light illumination; YtvA-LOV without the J? helix dimerized in the dark state but existed as a monomer in the light state. The absence of the J? helix also affected the dark regeneration kinetics and the stability of the flavin mononucleotide (FMN) binding to its binding site. Our results demonstrate an alternative way of photo-induced signal propagation that leads to a bigger functional response through dimer/monomer conversions of the YtvA-LOV than the local disruption of J? helix in the As-LOV domain.

SUBMITTER: Lee R 

PROVIDER: S-EPMC4815236 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature