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Hemimastigophora es un nuevo linaje de eucariotas de nivel supra-reino

  • 0Department of Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada.
Nature +

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16 de noviembre de 2018

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16 de noviembre de 2018

Ver abstracta en PubMed

Resumen

Este resumen es generado por máquina.

Los investigadores han colocado filogenéticamente el único grupo Hemimastigophora, previamente no asignado, como un linaje supra-reino independiente. Este descubrimiento remodela nuestra comprensión de la evolución eucariota y el último antepasado común eucariota.

Área De La Ciencia

  • Evolución de los eucariotas
  • Protistología
  • Filogenética molecular

Sus Antecedentes

  • La mayoría de los eucariotas se clasifican filogenéticamente, pero Hemimastigophora permanece sin asignar.
  • Los hemimastigotas son protistas depredadores morfológicamente distintos con estructuras celulares únicas.
  • No se disponía previamente de datos moleculares o cultivos para Hemimastigophora.

Objetivo Del Estudio

  • Para determinar la posición filogenética de Hemimastigophora dentro del árbol de la vida eucariota.
  • Investigar el significado evolutivo de Hemimastigophora para comprender las divergencias eucarióticas profundas.
  • Establecer un modelo cultivable para futuros estudios genómicos y de biología celular.

Principales Métodos

  • Análisis filogenómicos que utilicen transcriptomía de alto alcance e independiente del cultivo.
  • Análisis comparativo con supergrupos de eucariotas establecidos.
  • Establecimiento del primer cultivo de Hemimastigote (Hemimastix kukwesjijk sp. No obstante, el

Principales Resultados

  • Hemimastigophora se coloca fuera de todos los supergrupos de eucariotas establecidos.
  • Este linaje forma un grupo de nivel supra-reino independiente.
  • Es probable que sea un clado hermano del supergrupo 'Diaphoretickes', que afecta a la topología del árbol eucariota.
  • Se estableció con éxito el primer cultivo de Hemimastix kukwesjijk.

Conclusiones

  • Hemimastigophora representa un linaje evolutivo importante y previamente no reconocido de eucariotas.
  • Su ubicación filogenética requiere una reevaluación de la clasificación eucariota y la historia evolutiva profunda.
  • La nueva cultura proporciona un recurso vital para futuras investigaciones sobre los orígenes de los eucariotas y el último antepasado común eucariota.

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