Year: 2022
Type: review
Abstract: SUMMARY Reactive oxygen species (ROS) such as singlet oxygen, superoxide (O 2 ●− ) and hydrogen peroxide (H 2 O 2 ) are the markers of living cells. Oxygenic photosynthesis produces ROS in abundance, which act as a readout of a functional electron transport system and metabolism. The concept that photosynthetic ROS production is a major driving force in chloroplast to nucleus retrograde signalling is embedded in the literature, as is the role of chloroplasts as environmental sensors. The different complexes and components of the photosynthetic electron transport chain (PETC) regulate O 2 ●− production in relation to light energy availability and the redox state of the stromal Cys‐based redox systems. All of the ROS generated in chloroplasts have the potential to act as signals and there are many sulphhydryl‐containing proteins and peptides in chloroplasts that have the potential to act as H 2 O 2 sensors and function in signal transduction. While ROS may directly move out of the chloroplasts to other cellular compartments, ROS signalling pathways can only be triggered if appropriate ROS‐sensing proteins are present at or near the site of ROS production. Chloroplast antioxidant systems serve either to propagate these signals or to remove excess ROS that cannot effectively be harnessed in signalling. The key challenge is to understand how regulated ROS delivery from the PETC to the Cys‐based redox machinery is organised to transmit redox signals from the environment to the nucleus. Redox changes associated with stromal carbohydrate metabolism also play a key role in chloroplast signalling pathways.
Source: The Plant Journal
DOI: 10.1111/tpj.15856
Authors: Christine H. Foyer, Guy Hanke
Institutions: University of Birmingham, Queen Mary University of London
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,800
OpenAlex ID: W4281643745