biostudies-literatureRomero-Losada ABBBSRC PioneerWellcome Trust DiscoveryELECTRASpanish Ministry of Science and InnovationMINOTAURWellcome TrustJunta de Andalucia predoctoralkoaf033https://www.ebi.ac.uk/biostudies/studies/S-EPMC12216367biostudies-literatureUnknown37(2)Earth's tilted rotation and translation around the Sun produce pervasive rhythms on our planet, giving rise to photoperiodic changes in diel cycles. Although marine phytoplankton plays a key role in ecosystems, multiomics analysis of its responses to these periodic environmental signals remains largely unexplored. The marine picoalga Ostreococcus tauri was chosen as a model organism due to its cellular and genomic simplicity. Ostreococcus was subjected to different light regimes to investigate its responses to periodic environmental signals: long summer days, short winter days, constant light, and constant dark conditions. Although <5% of the transcriptome maintained oscillations under both constant conditions, 80% presented diel rhythmicity. A drastic reduction in diel rhythmicity was obsThe Plant cellMultiomics integration unveils photoperiodic plasticity in the molecular rhythms of marine phytoplankton.PMC12216367225212/Z/22/ZPID2021-123984OB-I00PREDOC_00999APP3975Morales-Pineda MGarcia-Gonzalez MRomero-Campero FJRomero-Losada ABArvanitidou CCastro-Perez MJvan Ooijen GGarcia-Gomez MEChew YPfalseMultiomics integration unveils photoperiodic plasticity in the molecular rhythms of marine phytoplankton.Earth's tilted rotation and translation around the Sun produce pervasive rhythms on our planet, giving rise to photoperiodic changes in diel cycles. Although marine phytoplankton plays a key role in ecosystems, multiomics analysis of its responses to these periodic environmental signals remains largely unexplored. The marine picoalga Ostreococcus tauri was chosen as a model organism due to its cellular and genomic simplicity. Ostreococcus was subjected to different light regimes to investigate its responses to periodic environmental signals: long summer days, short winter days, constant light, and constant dark conditions. Although <5% of the transcriptome maintained oscillations under both constant conditions, 80% presented diel rhythmicity. A drastic reduction in diel rhythmicity was obs2025-01-01T00:00:00Z2025 Feb2026-05-27T09:41:15.331Z2026-05-27T03:07:56.311ZS-EPMC122163673993293910.1093/plcell/koaf033