title: Endosymbiosis and Eukaryotic Cell Evolution.
abstract: Understanding the evolution of eukaryotic cellular complexity is one of the grand challenges of modern biology. It has now been firmly established that mitochondria and plastids, the classical membrane-bound organelles of eukaryotic cells, evolved from bacteria by endosymbiosis. In the case of mitochondria, evidence points very clearly to an endosymbiont of α-proteobacterial ancestry. The precise nature of the host cell that partnered with this endosymbiont is, however, very much an open question. And while the host for the cyanobacterial progenitor of the plastid was undoubtedly a fully-fledged eukaryote, how - and how often - plastids moved from one eukaryote to another during algal diversification is vigorously debated. In this article I frame modern views on endosymbiotic theory in a historical context, highlighting the transformative role DNA sequencing played in solving early problems in eukaryotic cell evolution, and posing key unanswered questions emerging from the age of comparative genomics.
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, Halifax, Nova Scotia, B3H 4R2, Canada, and Program in Integrated Microbial Biodiversity, Canadian Institute for Advanced Research, Toronto, Ontario, M5G 1Z8, Canada. Electronic address: John.Archibald@Dal.Ca.
authors.forename: John M
authors.initials: JM
authors.lastname: Archibald
mesh_terms: D005075:Biological Evolution; D056890:Eukaryota / Q000502:physiology*; D005057:Eukaryotic Cells / Q000502:physiology*; D019143:Evolution, Molecular; D023281:Genomics; D015388:Organelles / Q000502:physiology*; D017422:Sequence Analysis, DNA; D013559:Symbiosis