Decoding the molecular mechanism of glyoxylase-like;11 in photoprotection

• Applicant: Professorin Dr. Veronica Maurino
• Subject Area: Plant Physiology
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 568275829

In the intricate dance of nature, plants constantly adapt to changing environmental conditions to ensure optimal growth and survival. Among these, the ability to adapt to high light (HL) is critical as the risk of photooxidative damage is high. Photoinhibition, a consequence of excessive light, disrupts chloroplast photochemistry, leading to reduced photosynthetic efficiency and the generation of reactive oxygen species and reactive carbonyl species (RCS). To counteract these detrimental effects, plants employ several energy-consuming adaptations, including rapid component replacement, heat dissipation strategies, cyclic electron flow, and reactive species scavenging systems. Among these, the glyoxalase system plays a central role in the detoxification of RCS, with glyoxalase-like;11 (GL11) emerging as a key player. Our preliminary studies indicated that GL11 is localized in the chloroplast and is co-expressed with chloroplastic proteins involved in photoprotection. Signs of photoinhibition and photosynthetic defects under HL are shown by a GL11 loss-of-function mutant, while complemented lines restore the wild-type phenotype. Furthermore, alterations in the xanthophyll cycle components and enhanced non-photochemical quenching are revealed by the gl11 mutant response to HL treatment, suggesting a link between GL11, zeaxanthin accumulation and photoprotective responses. In this project, a multifaceted investigation will be undertaken to elucidate the role of GL11 in HL acclimation. Our goals are to elucidate the involvement of GL11 in HL acclimation and to discover the molecular function of GL11. We will combine state-of-the-art biochemical and physiological analyses with the use of genetically encoded reporters and proximity labeling. The proposed research will allow us to elucidate the role of a newly discovered factor in the intricate mechanisms of photoprotection.

• DFG Programme: Research Grants