The journal Nature Ecology and Evolution has featured his research on symbiosis and cell evolution, published last March in the journal Cell, in its ‘Year in Review’ section, which highlights the 10 most relevant scientific advances of 2024.
The journal Nature Ecology and Evolution has included the research led by Francisco Cornejo, a researcher at the Institut de Ciències del Mar (ICM-CSIC), in its ‘Year in Review’ section, which highlights the 10 most relevant scientific advances of 2024. The journal emphasizes two nearly simultaneous studies that pointed to the discovery of the first nitrogen-fixing organelle in eukaryotes, named “nitroplast”, which has garnered significant attention from the international scientific community.
The study of Cornejo and collaborators, published in Cell last March, focuses on the symbiotic relationship between marine microalgal species closely related to Braarudosphaera bigelowii and the cyanobacterium Candidatus Atelocyanobacterium thalassa (UCYN-A). Their findings reveal that UCYN-A exhibits organelle-like characteristics, including a size relationship between the endosymbiont and its algal host that closely mirrors that observed between mitochondria or chloroplasts (cellular organelles) and their host cells. The study shows that this size ratio optimizes the nutrient exchange between UCYN-A and the host cell, suggesting that UCYN-A may no longer be merely an endosymbiont organism but an integrated functional structure, the so-called nitroplast, capable of fixing nitrogen and supplying it to the algal host.
"The role played by ICM-CSIC has been crucial to this discovery. In particular, it is worth mentioning the efforts of my colleagues Ana María Cabello and Ramon Massana, who already in 2016 developed molecular tools for detecting and observing this microscopic symbiosis in natural samples, as well as the role of Silvia Acinas, with whom we started to disentangle the evolution of this fascinating symbiotic system almost 10 years ago" says Cornejo.
This recognition by Nature Ecology and Evolution follows a previous one by Science, which last December described this discovery as one of the scientific breakthroughs of 2024. The findings published in Cell were strongly supported by a follow-up study in Science, providing conclusive evidence of UCYN-A’s tight integration into the cellular architecture of B. bigelowii.
Overall, this research offers new perspectives on the evolution of the eukaryotic cell complexity through the development of organelles, underscoring the significance of fundamental marine science research in addressing broad, far-reaching questions.
"In the long term, this work could also contribute to developing biotechnological tools with applications in agriculture, such as nitrogen-fixing plants. Such innovations could reduce the need for chemical fertilizers and promote more sustainable agricultural practices," concludes Cornejo.