Light-sensing via hydrogen peroxide and a peroxiredoxin.

Bodvard K, Peeters K, Roger F, Romanov N, Igbaria A, Welkenhuysen N, Palais G, Reiter W, Toledano MB, Käll M, Molin M

Nat Commun 8 (1) 14791 [2017-03-24; online 2017-03-24]

Yeast lacks dedicated photoreceptors; however, blue light still causes pronounced oscillations of the transcription factor Msn2 into and out of the nucleus. Here we show that this poorly understood phenomenon is initiated by a peroxisomal oxidase, which converts light into a hydrogen peroxide (H 2O2) signal that is sensed by the peroxiredoxin Tsa1 and transduced to thioredoxin, to counteract PKA-dependent Msn2 phosphorylation. Upon H2O2, the nuclear retention of PKA catalytic subunits, which contributes to delayed Msn2 nuclear concentration, is antagonized in a Tsa1-dependent manner. Conversely, peroxiredoxin hyperoxidation interrupts the H2O2 signal and drives Msn2 oscillations by superimposing on PKA feedback regulation. Our data identify a mechanism by which light could be sensed in all cells lacking dedicated photoreceptors. In particular, the use of H2O2 as a second messenger in signalling is common to Msn2 oscillations and to light-induced entrainment of circadian rhythms and suggests conserved roles for peroxiredoxins in endogenous rhythms.

Integrated Microscopy Technologies Gothenburg [Service]

PubMed 28337980

DOI 10.1038/ncomms14791

Crossref 10.1038/ncomms14791

pii: ncomms14791
pmc: PMC5376668