Study Sheds Light on Algae's Ability to Respond to Different Levels of Light, Carbon Dioxide

New details about the molecular mechanisms underlying green algae's ability to respond to varying levels of sunlight and carbon dioxide (CO₂) are reported in Nature Communications this week. Light and CO₂ are substrates of microalgae photosynthesis and their availability often fluctuates. Under strong light, microalgae activate photoprotection to prevent oxidative damage, while low CO₂ triggers their CO₂ Concentrating Mechanism to raise intracellular CO₂ levels. While these processes are vital to algae's survival and represent valuable targets for biological engineering, their underlying transcriptional regulators are largely unknown. Aiming to elucidate the gene regulatory network (GRN) underlying the green algae Chlamydomonas reinhardtii's responses to light and carbon availability, scientists from the University of Potsdam and collaborators used an RNA sequencing compendium of 158 samples from Chlamydomonas cultures exposed to different light and carbon supplies as input to seven benchmarked GRN-inference approaches that employ complementary inference strategies to identify activating and inhibiting regulatory interactions. The results of the five best-performing approaches were combined into a consensus network of Chlamydomonas light- and carbon-dependent transcriptional regulation. "Our study provides an accessible resource to dissect gene expression regulation in this microalga," the scientists write.