Plants use light as an environmental sensor and as a source of energy to drive photosynthesis. Photosynthesis converts light energy into chemical energy and provides the fundamental molecules to sustain metabolism, including synthesis of the building blocks required for cell division, expansion and maintenance, production of stress and defense metabolites, and ultimately plant growth. Photosynthetic electron transport via photochemical redox reactions terminates at photosystem I (PSI), beyond which electrons move to oxidized acceptors in the chloroplast stroma. Metabolic reactions that consume reducing power in the stroma include CO2 fixation and carbohydrate synthesis, as well as chloroplast redox networks and scavenging reactive oxygen species (ROS). PSI, therefore, sits at the juncture between the generation of reducing power by light reactions and the allocation of the reducing power to metabolic reactions in the chloroplast and beyond.
Primary metabolism, including the Calvin-Benson assimilative cycle, is coordinated with PSI redox state by several mechanisms to adapt their respective activities to developmental and environmental cues. For instance, light and photosynthetic efficiency regulate gene expression and affect the redox states of stromal regulatory systems (e.g., thioredoxins) that are crucial in modulating the activity of enzymes of the Calvin-Benson cycle. On the other hand, metabolic reprogramming as a consequence of environmental stress conditions is linked with changes to stroma redox dynamics, which have a direct effect on PSI activity. Therefore, both primary metabolism and PSI activity are tightly connected and profoundly susceptible to unfavorable conditions. Thus, any event that triggers an uncoupling between PSI redox status and (photosynthetic) metabolism negatively affects plant fitness, growth, and yield.
This Research Topic aims to collect articles addressing the latest advances related to the crosstalk between PSI activity and metabolism in plants, algae, and cyanobacteria. Articles addressing the following subjects are especially encouraged:
• Efficiency and regulation of PSI electron transport activity
• Inhibition and repair of PSI
• PSI activity on metabolic outputs, aspects of photosynthetic electron transport, chloroplast redox/antioxidant networks, ROS production or chloroplast signaling
• Impact of altered photosynthetic metabolism on PSI activity, photosynthate production/allocation, and plant growth
• Effect of environmental perturbations and developmental status on metabolism and its influence on photosynthetic electron flow and PSI activity
• Genotypic variation on PSI activity and/or photosynthetic metabolic components with impact on development or growth
• Crosstalk between circadian regulation and PSI activity
• Impact of light quality, duration and variation on PSI activity and/or the allocation of energy between carbohydrate, ROS and growth
• Impact of metabolic status on the regulation PSI activity and/or the allocation of energy between carbohydrate/ROS and growth
• Impact of light sensing or signaling components on PSI activity and their effects on the downstream chloroplast redox network/metabolism
We welcome submissions of Original Research, Reviews and Mini Reviews, Perspectives, Opinions, Methods, or Hypothesis and Theory.
Image credit: Peter Gollan.
Plants use light as an environmental sensor and as a source of energy to drive photosynthesis. Photosynthesis converts light energy into chemical energy and provides the fundamental molecules to sustain metabolism, including synthesis of the building blocks required for cell division, expansion and maintenance, production of stress and defense metabolites, and ultimately plant growth. Photosynthetic electron transport via photochemical redox reactions terminates at photosystem I (PSI), beyond which electrons move to oxidized acceptors in the chloroplast stroma. Metabolic reactions that consume reducing power in the stroma include CO2 fixation and carbohydrate synthesis, as well as chloroplast redox networks and scavenging reactive oxygen species (ROS). PSI, therefore, sits at the juncture between the generation of reducing power by light reactions and the allocation of the reducing power to metabolic reactions in the chloroplast and beyond.
Primary metabolism, including the Calvin-Benson assimilative cycle, is coordinated with PSI redox state by several mechanisms to adapt their respective activities to developmental and environmental cues. For instance, light and photosynthetic efficiency regulate gene expression and affect the redox states of stromal regulatory systems (e.g., thioredoxins) that are crucial in modulating the activity of enzymes of the Calvin-Benson cycle. On the other hand, metabolic reprogramming as a consequence of environmental stress conditions is linked with changes to stroma redox dynamics, which have a direct effect on PSI activity. Therefore, both primary metabolism and PSI activity are tightly connected and profoundly susceptible to unfavorable conditions. Thus, any event that triggers an uncoupling between PSI redox status and (photosynthetic) metabolism negatively affects plant fitness, growth, and yield.
This Research Topic aims to collect articles addressing the latest advances related to the crosstalk between PSI activity and metabolism in plants, algae, and cyanobacteria. Articles addressing the following subjects are especially encouraged:
• Efficiency and regulation of PSI electron transport activity
• Inhibition and repair of PSI
• PSI activity on metabolic outputs, aspects of photosynthetic electron transport, chloroplast redox/antioxidant networks, ROS production or chloroplast signaling
• Impact of altered photosynthetic metabolism on PSI activity, photosynthate production/allocation, and plant growth
• Effect of environmental perturbations and developmental status on metabolism and its influence on photosynthetic electron flow and PSI activity
• Genotypic variation on PSI activity and/or photosynthetic metabolic components with impact on development or growth
• Crosstalk between circadian regulation and PSI activity
• Impact of light quality, duration and variation on PSI activity and/or the allocation of energy between carbohydrate, ROS and growth
• Impact of metabolic status on the regulation PSI activity and/or the allocation of energy between carbohydrate/ROS and growth
• Impact of light sensing or signaling components on PSI activity and their effects on the downstream chloroplast redox network/metabolism
We welcome submissions of Original Research, Reviews and Mini Reviews, Perspectives, Opinions, Methods, or Hypothesis and Theory.
Image credit: Peter Gollan.
