Were eukaryotes made by sex?: Sex might have been vital for merging endosymbiont and host genomes giving rise to eukaryotes. (16th April 2021)

• Record Type: Journal Article
• Authors: Brandeis, Michael
• Is Part Of: BioEssays. Volume 43:Number 6(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-04-16
• Subjects: endosymbiosis -- eukaryogenesis -- evolution of sex -- meiosis -- mitochondrial DNA; Molecular biology -- Periodicals; Cytology -- Periodicals; Developmental biology -- Periodicals; 572.8
• DOI: 10.1002/bies.202000256
• Languages: English
• ISSNs: 0265-9247

Abstract

Abstract: I hypothesize that the appearance of sex facilitated the merging of the endosymbiont and host genomes during early eukaryote evolution. Eukaryotes were formed by symbiosis between a bacterium that entered an archaeon, eventually giving rise to mitochondria. This entry was followed by the gradual transfer of most bacterial endosymbiont genes into the archaeal host genome. I argue that the merging of the mitochondrial genes into the host genome was vital for the evolution of genuine eukaryotes. At the time this process commenced it was unprecedented and required a novel mechanism. I suggest that this mechanism was meiotic sex, and that its appearance might have been THE crucial step that enabled the evolution of proper eukaryotes from early endosymbiont containing proto‐eukaryotes. Sex might continue to be essential today for keeping genome insertions in check. Also see the video abstract here: https://youtu.be/aVMvWMpomac Abstract : A novel hypothesis that tries to explain the importance of meiotic sex for the evolution of genuine and complex eukaryotic cells is presented here. In this hypothesis it is proposed that, after endosymbiosis, sex was required for the vital process of the transfer of the mitochondrial genes into the nuclear genome.