METHYLENE BLUE SENSITIVITY 1 (MBS1) is required for acclimation of Arabidopsis to singlet oxygen and acts downstream of β-cyclocitral

Leonard Shumbe (1) , Stefano d'Alessandro (1) , Ning Shao (2) , Anne Chevalier (3) , Brigitte Ksas (3) , Ralph Bock (2) , Michel Havaux (1, 4)

1 BIAM - Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB)
2 MPI-MP - Max-Planck-Institut für Molekulare Pflanzenphysiologie
3 BVME - Biologie végétale et microbiologie environnementale - UMR7265
4 PEPSS - Plant Environmental Physiology and Stress Signaling

Singlet oxygen (1 O 2) signalling in plants is essential to trigger both acclimatory mechanisms and programmed cell death under high light stress. However, because of its chemical features, 1 O 2 requires mediators, and the players involved in this pathway are largely unknown. The β-carotene oxidation product, β-cyclocitral, is one such mediator. Produced in the chloroplast, β-cyclocitral induces changes in nuclear gene expression leading to photoacclimation. Recently, the METHYLENE BLUE SENSITIVITY protein MBS has been identified as a key player in 1 O 2 signalling leading to tolerance to high light. Here, we provide evidence that MBS1 is essential for acclimation to 1 O 2 and cross-talks with β-cyclocitral to mediate transfer of the 1 O 2 signal to the nucleus, leading to photoacclimation. The presented results position MBS1 downstream of β-cyclocitral in 1 O 2 signalling and suggest an additional role for MBS1 in the regulation of plant growth and development under chronic 1 O 2 production.

Domaines: Biologie végétale

Leonard Shumbe, Stefano d'Alessandro, Ning Shao, Anne Chevalier, Brigitte Ksas, et al.. METHYLENE BLUE SENSITIVITY 1 (MBS1) is required for acclimation of Arabidopsis to singlet oxygen and acts downstream of β-cyclocitral. Plant, Cell and Environment, 2017, 40 (2), pp.216 - 226. ⟨10.1111/pce.12856⟩. ⟨hal-01682743⟩