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Patterns of Gene Flow Define Species of Thermophilic Archaea

Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene...

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Autores principales: Cadillo-Quiroz, Hinsby, Didelot, Xavier, Held, Nicole L., Herrera, Alfa, Darling, Aaron, Reno, Michael L., Krause, David J., Whitaker, Rachel J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3283564/
https://www.ncbi.nlm.nih.gov/pubmed/22363207
http://dx.doi.org/10.1371/journal.pbio.1001265
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author Cadillo-Quiroz, Hinsby
Didelot, Xavier
Held, Nicole L.
Herrera, Alfa
Darling, Aaron
Reno, Michael L.
Krause, David J.
Whitaker, Rachel J.
author_facet Cadillo-Quiroz, Hinsby
Didelot, Xavier
Held, Nicole L.
Herrera, Alfa
Darling, Aaron
Reno, Michael L.
Krause, David J.
Whitaker, Rachel J.
author_sort Cadillo-Quiroz, Hinsby
collection PubMed
description Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene flow among genomes of 12 strains from a single hot spring in Kamchatka, Russia, demonstrate higher levels of gene flow within than between two persistent, coexisting groups, demonstrating that these microorganisms fit the biological species concept. Furthermore, rates of gene flow between two species are decreasing over time in a manner consistent with incipient speciation. Unlike other microorganisms investigated, we do not observe a relationship between genetic divergence and frequency of recombination along a chromosome, or other physical mechanisms that would reduce gene flow between lineages. Each species has its own genetic island encoding unique physiological functions and a unique growth phenotype that may be indicative of ecological specialization. Genetic differentiation between these coexisting groups occurs in large genomic “continents,” indicating the topology of genomic divergence during speciation is not uniform and is not associated with a single locus under strong diversifying selection. These data support a model where species do not require physical barriers to gene flow but are maintained by ecological differentiation.
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spelling pubmed-32835642012-02-23 Patterns of Gene Flow Define Species of Thermophilic Archaea Cadillo-Quiroz, Hinsby Didelot, Xavier Held, Nicole L. Herrera, Alfa Darling, Aaron Reno, Michael L. Krause, David J. Whitaker, Rachel J. PLoS Biol Research Article Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene flow among genomes of 12 strains from a single hot spring in Kamchatka, Russia, demonstrate higher levels of gene flow within than between two persistent, coexisting groups, demonstrating that these microorganisms fit the biological species concept. Furthermore, rates of gene flow between two species are decreasing over time in a manner consistent with incipient speciation. Unlike other microorganisms investigated, we do not observe a relationship between genetic divergence and frequency of recombination along a chromosome, or other physical mechanisms that would reduce gene flow between lineages. Each species has its own genetic island encoding unique physiological functions and a unique growth phenotype that may be indicative of ecological specialization. Genetic differentiation between these coexisting groups occurs in large genomic “continents,” indicating the topology of genomic divergence during speciation is not uniform and is not associated with a single locus under strong diversifying selection. These data support a model where species do not require physical barriers to gene flow but are maintained by ecological differentiation. Public Library of Science 2012-02-21 /pmc/articles/PMC3283564/ /pubmed/22363207 http://dx.doi.org/10.1371/journal.pbio.1001265 Text en Cadillo-Quiroz et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Cadillo-Quiroz, Hinsby
Didelot, Xavier
Held, Nicole L.
Herrera, Alfa
Darling, Aaron
Reno, Michael L.
Krause, David J.
Whitaker, Rachel J.
Patterns of Gene Flow Define Species of Thermophilic Archaea
title Patterns of Gene Flow Define Species of Thermophilic Archaea
title_full Patterns of Gene Flow Define Species of Thermophilic Archaea
title_fullStr Patterns of Gene Flow Define Species of Thermophilic Archaea
title_full_unstemmed Patterns of Gene Flow Define Species of Thermophilic Archaea
title_short Patterns of Gene Flow Define Species of Thermophilic Archaea
title_sort patterns of gene flow define species of thermophilic archaea
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3283564/
https://www.ncbi.nlm.nih.gov/pubmed/22363207
http://dx.doi.org/10.1371/journal.pbio.1001265
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