The emergence of eukaryotes as an evolutionary algorithmic phase transition
A recent paper by Jordi Bascompte published in PNAS has shown how the eukaryotic cell emerged as a compromise between a conserved process of gene growth and a change in genetic regulation.
For almost half the history of life on earth, the complexity of all organisms was limited to that of simple prokaryotic cells such as contemporary bacteria. It is well established that the emergence of the eukaryotic cell---characterized by membrane-bound nucleus and organelles---arose from the symbiosis between two previously unrelated organisms, an archaeon host cell and a bacterium. Without this evolutionary event, the posterior evolution of multicellular organisms represented by animals, land plants, and the majority of fungi would not have been possible. It was not clear, however, which balance of novelty and continuity in the underlying mechanisms of gene and protein evolution allowed this major reorganization of life.
A recent paper by Jordi Bascompte published in PNAS has shown how the eukaryotic cell emerged as a compromise between a conserved process of gene growth and a change in genetic regulation. Up to this evolutionary transition, genetic regulation in procaryotes was entirely determined by proteins. This set up a limit on cellular complexity, as finding even larger proteins became computationally unfeasible. Evolution found a way out by shifting to an alternative solution based on regulation by non-coding sequences.Read the full paper in PNAS
An article also appeared in "El País". Read the article (PDF, 390 KB)