Uma hipótese concernente o estabelecimento do endosimbionte protomitocondrial durante a eucariogênese

segunda-feira, janeiro 22, 2018

Journal of Molecular Evolution

October 2017, Volume 85, Issue 3–4, pp 99–106 | Cite as

Some Liked It Hot: A Hypothesis Regarding Establishment of the Proto-Mitochondrial Endosymbiont During Eukaryogenesis


Cory D. Dunn 1, 2

1. Email author View author's OrcID profile

1.Institute of Biotechnology, Helsinki Institute of Life Science University of Helsinki Finland

2.College of Sciences Koç University Sarıyer Turkey

Open Access Original Article

First Online: 15 September 2017


Eukaryotic cells are characterized by a considerable increase in subcellular compartmentalization when compared to prokaryotes. Most evidence suggests that the earliest eukaryotes consisted of mitochondria derived from an α-proteobacterial ancestor enclosed within an archaeal host cell. However, what benefits the archaeal host and the proto-mitochondrial endosymbiont might have obtained at the beginning of this endosymbiotic relationship remains unclear. In this work, I argue that heat generated by the proto-mitochondrion initially permitted an archaeon living at high temperatures to colonize a cooler environment, thereby removing apparent limitations on cellular complexity. Furthermore, heat generation by the endosymbiont would have provided phenotypic flexibility not available through fixed alleles selected for fitness at specific temperatures. Finally, a role for heat production by the proto-mitochondrion bridges a conceptual gap between initial endosymbiont entry to the archaeal host and a later role for mitochondrial ATP production in permitting increased cellular complexity.

Keywords Endosymbiosis Eukaryogenesis Mitochondria Archaea Temperature Bioenergetics