Light-sensing via hydrogen peroxide and a peroxiredoxin

Kristofer Bodvard (1, 2) , Ken Peeters (1) , Friederike Roger (1) , Natalie Romanov (3) , Aeid Igbaria (4) , Niek Welkenhuysen (1) , Gael Palais (4) , Wolfgang Reiter (5) , Michel B. Toledano (4) , Mikael Käll (2) , Mikael Molin (1)

1 GU - Göteborgs Universitet = University of Gothenburg
2 Chalmers University of Technology [Göteborg]
3 Mass Spectrometry Facility, Max F. Perutz Laboratories,
4 SBIGeM - Service de Biologie Intégrative et Génétique Moléculaire
5 Department of Biochemistry, Max F. Perutz Laboratories, University of Vienna, Dr Bohrgasse 9, A-1030 Vienna, Austria.

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$_2$ O$_2$) signal that is sensed by the peroxiredoxin Tsa1 and transduced to thioredoxin, to counteract PKA-dependent Msn2 phosphorylation. Upon H$_2$ O$_2$ , 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 H$_2$ O$_2$ 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 H$_2$ O$_2$ 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.

Domaines: Chimie; Biochimie, Biologie Moléculaire

Kristofer Bodvard, Ken Peeters, Friederike Roger, Natalie Romanov, Aeid Igbaria, et al.. Light-sensing via hydrogen peroxide and a peroxiredoxin. Nature Communications, 2017, 8, pp.14791. ⟨10.1038/ncomms14791⟩. ⟨cea-02139188⟩