An Ectosymbiosis-Based Mechanism of Eukaryogenesis
Main Article Content
Abstract
The mechanisms proposed for eukaryogenesis are divisible into mitochondria-early and mitochondria-late ones, where the mitochondriate-eukaryotes were evolutionary precursors or products of the amitochondriate-eukaryotes respectively. Analysis of prokaryote-to-eukaryote gene transfers in eukaryogenesis showed two tranches of high-intensity transfers from prokaryotes to eukaryotes mediated by the endosymbioses that gave rise to mitochondria and chloroplasts, and hundreds of medium-intensity transfers which included the transfer of hydrogenase and pyruvate: ferredoxin oxidoreductase genes from the Thermoanaerobacter-Hungateiclostridium-Sporanaerobacter group of bacteria to the amitochondriate eukaryotes. Since 94.5% of these medium-intensity transfers generated more than 100 inter-proteome similarity hits between each donor-recipient pair, they were not readily explicable by horizontal gene transfers or endosymbioses, pointing instead to the participation of a huge number of ectosymbiotic transfers. The euryarchaeon Aciduliprofundum boonei and the gammaproteobacterium Escherichia coli were among the foremost contributors of archaeal and bacterial genes to the eukaryotic DNA-apparati respectively, and the ratios of the genes in different eukaryotes indicated that Microsporidia have retained more of the genomic imprint of Aciduliprofundum than all other eukaryotes. These findings supported an ectosymbiosis-based mechanism of eukaryogenesis with Aciduliprofundum as the Archaeal Parent of Eukarya, and Microsporidia as the eukaryotes phylogenetically closest to the Last Eukaryotic Common Ancestor.
Keywords:
Aciduliprofundum, archaeal parent, ectosymbiosis, endosymbiosis, eukaryogenesis, valyl-tRNA synthetase
Article Details
How to Cite
WONG, Tze-Fei et al.
An Ectosymbiosis-Based Mechanism of Eukaryogenesis.
Medical Research Archives, [S.l.], v. 11, n. 1, jan. 2023.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/3365>. Date accessed: 25 apr. 2024.
doi: https://doi.org/10.18103/mra.v11i1.3365.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
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17. Horner DS, Hirt RP, Kilvington S, Lloyd D, Embley TM. Molecular data suggest an early acquisition of the mitochondrion endosymbiont. Proc Biol Sci 1996;263(1373):1053-1059. doi:10.1098/rspb.1996.0155.
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23. Martin WF, Roettger M, Ku C, Garg SG, Nelson-Sathi S, Landan G. Late mitochondrial origin is an artifact. Genome Biol Evol 2017;9(2):373-379. doi:10.1093/gbe/evx027.
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25. Esser C, Ahmadinejad N, Wiegand C, Rotte C, Sebastiani F, Gelius-Dietrich G, Henze K, Kretschmann E, Richly E, Leister D, et al. A genome phylogeny for mitochondria among alpha-proteobacteria and a predominantly eubacterial ancestry of yeast nuclear genes. Mol Biol Evol 2004; 21: 1643-1660. doi: 10.1093/molbev/msh160.
26. Rochette NC, Brochier-Armanet C, Gouy M. Phylogenomic test of the hypotheses for the evolutionary origin of eukaryotes. Mol Biol Evol 2014; 31: 832-845. doi: 10.1093/molbev/mst27.
27. Blanchard JL, Lynch M. Organellar genes: why do they end up in the nucleus?. Trends Genet 2000;16(7):315-320. doi:10.1016/s0168-9525(00)02053-9.
28. Clark K, Karsch-Mizrachi I, Lipman DJ, Ostell J, W. Sayers E, et al. GenBank. Nucleic Acids Res. 2016; 44 D67-72. doi: 10.1093/nar/gkv127.
29. O'Leary NA, Wright MW, Brister JR, Ciufo S, Haddad D, et al. Reference sequence (RefSeq) database at NCBI: current status, taxonomic expansion, and functional annotation. Nucl Acid Res. 2016; 44: D733-745. doi: 10.1093/nar/gkv1189.
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31. Enderlin CS, Meeks JC. Pure culture and reconstitution of the Anthoceros-Nostoc symbiotic association. Planta. 1983; 158: 157-165. Doi: 10.1007/BF00397709.
32. Hétérier V, David B, De Ridder C, Rigaud T. Ectosymbiosis is a critical factor in the local benthic biodiversity of the Antarctic deep sea. Mar Ecol Prog Ser. Published online 2008. doi:10.3354/meps07487.
33. Noda S, Ohkuma M, Yamada A, Hongoh Y, Kudo T. Phylogenetic position and in situ identification of ectosymbiotic spirochetes on protists in the termite gut. Appl Environ Microbiol. 2003;69(1):625-633. doi:10.1128/AEM.69.1.625-633.2003.
34. Golyshina OV, Toshchakov SV, Makarova KS, et al. 'ARMAN' archaea depend on association with euryarchaeal host in culture and in situ. Nat Commun. 2017;8(1):60. Published 2017 Jul 5. doi:10.1038/s41467-017-00104-7.
35. Bauermeister J, Ramette A, Dattagupta S. Repeatedly evolved host-specific ectosymbioses between sulfur-oxidizing bacteria and amphipods living in a cave ecosystem. PLoS One. 2012;7(11):e50254. doi:10.1371/journal.pone.0050254.
36. Tatusov RL, Galperin MY, Natale DA, Koonin EV. The COG database: a tool for genome-scale analysis of protein functions and evolution. Nucleic Acids Res. 2000;28(1):33-36. doi:10.1093/nar/28.1.33.
37. Andersson SG, Kurland CG. Origins of mitochondria and hydrogenosomes. Curr Opin Microbiol. 1999;2(5):535-541. doi:10.1016/s1369-5274(99)00013-2.
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