Circadian regulation of metabolism across photosynthetic organisms

Abstract

SUMMARYCircadian regulation produces a biological measure of time within cells. The daily cycle in the availability of light for photosynthesis causes dramatic changes in biochemical processes in photosynthetic organisms, with the circadian clock having crucial roles in adaptation to these fluctuating conditions. Correct alignment between the circadian clock and environmental day–night cycles maximizes plant productivity through its regulation of metabolism. Therefore, the processes that integrate circadian regulation with metabolism are key to understanding how the circadian clock contributes to plant productivity. This forms an important part of exploiting knowledge of circadian regulation to enhance sustainable crop production. Here, we examine the roles of circadian regulation in metabolic processes in source and sink organ structures of Arabidopsis. We also evaluate possible roles for circadian regulation in root exudation processes that deposit carbon into the soil, and the nature of the rhythmic interactions between plants and their associated microbial communities. Finally, we examine shared and differing aspects of the circadian regulation of metabolism between Arabidopsis and other model photosynthetic organisms, and between circadian control of metabolism in photosynthetic and non‐photosynthetic organisms. This synthesis identifies a variety of future research topics, including a focus on metabolic processes that underlie biotic interactions within ecosystems.

Biological and genomic resources for the cosmopolitan phytoplanktonBathycoccus: Insights into genetic diversity and major structural variations

“…Mamiellophyceae diverged at the base of the green lineage, making them attractive models for studying essential cellular functions from an evolutionary perspective (Leliaert et al, 2012; Yung et al, 2022). The early whole genome sequencing of Ostreococcus tauri and the implementation of genetic transformation tools, including gene targeting by homologous recombination, have established O. tauri as a model for the study of several cellular pathways such as the circadian clock, the cell division, iron metabolism and vitamin B1 metabolism (Derelle et al, 2006; Corellou et al, 2009; Moulager et al, 2010; O’Neill et al, 2011; Van Oijen et al, 2013; Lozano et al, 2014; Botebol et al, 2015; Paerl et al, 2017; De Barros Dantas et al, 2023). The genomic content of O. tauri unveiled several features shared by Mamiellophyceae : A compact haploid genome, a majority of monoexonic genes, limited gene redundancy and two outlier chromosomes, characterized by lower GC content and unique gene structures, respectively named big outlier chromosome (BOC) and small outlier chromosome (SOC) (Derelle et al, 2006; Grimsley et al, 2015).…”