biostudies-literatureSchramma NEuropean Research Councile2411725121https://www.ebi.ac.uk/biostudies/studies/S-EPMC11588079biostudies-literatureUnknown121(47)Photosynthetic algae play a significant role in oceanic carbon capture. However, their performance is constantly challenged by fluctuations in environmental light conditions. While phototaxis is a common strategy to cope with such fluctuations, nonmotile species must adopt alternative mechanisms to avoid light-induced damage. Here, we show that the nonmotile, single-celled marine dinoflagellate <i>Pyrocystis lunula</i> contains a chloroplast network that undergoes strong deformation in response to strong light. By exposing cells to various physiologically relevant light conditions and applying temporal illumination sequences, we find that the light-induced network morphodynamics follows dynamic rules similar to temporal low-pass filtering. We develop a mathematical formalism to model the lProceedings of the National Academy of Sciences of the United States of AmericaLight-regulated chloroplast morphodynamics in a single-celled dinoflagellate.PMC115880791011170252023-StG-101117025Canales GCJalaal MSchramma NfalseLight-regulated chloroplast morphodynamics in a single-celled dinoflagellate.Photosynthetic algae play a significant role in oceanic carbon capture. However, their performance is constantly challenged by fluctuations in environmental light conditions. While phototaxis is a common strategy to cope with such fluctuations, nonmotile species must adopt alternative mechanisms to avoid light-induced damage. Here, we show that the nonmotile, single-celled marine dinoflagellate <i>Pyrocystis lunula</i> contains a chloroplast network that undergoes strong deformation in response to strong light. By exposing cells to various physiologically relevant light conditions and applying temporal illumination sequences, we find that the light-induced network morphodynamics follows dynamic rules similar to temporal low-pass filtering. We develop a mathematical formalism to model the l2024-01-01T00:00:00Z2024 Nov2026-06-02T18:37:25.599Z2025-04-04T00:46:34.424ZS-EPMC115880793954657210.1073/pnas.2411725121