On the ideas of the origin of eukaryotes: a critical review

Abstract

The origin and early evolution of eukaryotes are one of the major transitions in the evolution of life on earth. One of its most interesting aspects is the emergence of cellular organelles, their dynamics, their functions, and their divergence. Cell compartmentalization and architecture in prokaryotes is a less understood complex property. In eukaryotes it is related to cell size, specific genomic architecture, evolution of cell cycles, biogenesis of membranes and endosymbiotic processes. Explaining cell evolution through form and function demands an interdisciplinary approach focused on microbial diversity, phylogenetic and functional cell biology. Two centuries of views on eukaryotic origin have completed the disciplinary tools necessarily to answer these questions. We have moved from Haeckel SCALA NATURAE to the un-rooted tree of life. However, the major relations among cell domains are still elusive and keep the nature of eukaryotic ancestor enigmatic. Here we present a review on state of art views of eukaryogenesis; the background and perspectives of different disciplines involved in this topic