An international research team at Umeå University led by Assoc. Prof. Sanna Tärneberg has made a groundbreaking discovery, witnessing programmed cell death in microalgae for the first time. Their research shows for the first time that under normal physiological conditions, the microalga Guillardia theta undergoes apoptotic cell death. This process was once thought to be limited to complex multicellular organisms, like that of animals. This unique discovery may have important consequences towards comprehending the evolution of programmed cell death mechanisms.
Christian Funk and her conservation biology research team recently made a major scientific breakthrough. They discovered that Guillardia theta undergoes cell death that closely mimics the process in animal cells. During apoptosis, the process of cell death that leads to the formation of apoptotic bodies. This discovery makes Guillardia theta the first photosynthetic organism and the first unicellular organism of any sort ever recorded to produce such structures. This discovery raises the exciting prospect that the mechanisms of this process of programmed cell death are evolutionarily conserved, even in such diverse life forms.
Funk noted the importance of this discovery, stating, “This is the first photosynthetic organism, and the first single-cell organism, shown to produce so-called apoptotic bodies during cell death. This proves that apoptosis, a pathway of programmed cell death which was thought to be unique to animals, is more ancient and widespread than previously believed.”
The wider implications of this research go beyond evolutionary biology. Understanding how to induce or prevent programmed cell death in microorganisms like Guillardia theta could offer new strategies for managing harmful algal blooms. Moreover, these findings can improve harvesting procedures of algal-derived products in various biotechnological industries.
That work, released in the journal Nature Communications, reveals thrilling new opportunities for research to come. It’s about understanding the evolutionary origins of this type of programmed cell death. Funk elaborated on this notion, saying, “Our results demonstrate that the microalga Guillardia theta experiences apoptotic cell death in physiological conditions, similar to animal cells. Since these algae already existed prior to the origin of multicellularity, our discovery questions the evolutionary origin of PCD.”
Even more so, researchers are investigating the implications of programmed cell death in microalgae. Their provocative results have the potential to upend what we know about essential cellular processes across diverse forms of life. The study’s DOI is 10.1038/s41467-025-63956-4 providing access for those looking to learn more about this groundbreaking research.