Lessons in evolution from endosymbiosis involving algal hosts and bacterial long-term ‘guests’
Eukaryotic cells are complex miniature factories consisting of compartmentalised operations in membrane-bound organelles, among them mitochondria and chloroplasts. These energy powerhouses were likely prokaryotes that were engulfed by eukaryotes at some point, forming a symbiotic relationship. Such relationships are critical to evolution, yet the mechanisms remain largely a mystery. With the support of the Marie Skłodowska-Curie Actions programme, the UCYNELLE project is studying a recently discovered symbiosis between a bacterium and algae. A combination of experimental and field studies, genomics and metabolic rate versus cell size comparisons could shed light on the mechanisms of symbiosis and the acquisition of small organelles in eukaryotes.