Activation of s<SUP>20</SUP> -dependent recombination and horizontal gene transfer in <i>Mycoplasma genitalium</i>

In the human pathogen Mycoplasma genitalium, homologous recombination is under the control of sigma(20), an alternative sigma factor that boosts the generation of genetic and antigenic diversity in the population. Under laboratory growth conditions, sigma(20) activation is rare and the factors gover...

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Detalles Bibliográficos
Autores: Torres-Puig, S, Martínez-Torró, C, Granero-Moya, I, Querol, E, Piñol, J, Pich, OQ
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:España
Institución:Institut d'Investigació i Innovació Parc Taulí (I3PT)
Repositorio:r-I3PT. Repositorio Institucional Producción Científica del Institut d'Investigació i Innovació Parc Taulí
OAI Identifier:oai:i3pt.fundanetsuite.com:p5194
Acceso en línea:https://i3pt.portalinvestigacion.com/publicaciones/5194
Access Level:acceso abierto
Palabra clave:mycoplasma
sigma factor
homologous recombination
antigenic variation
horizontal gene transfer
Descripción
Sumario:In the human pathogen Mycoplasma genitalium, homologous recombination is under the control of sigma(20), an alternative sigma factor that boosts the generation of genetic and antigenic diversity in the population. Under laboratory growth conditions, sigma(20) activation is rare and the factors governing its intermittent activity are unknown. Two sigma(20)-regulated genes, rrlA and rrlB, showed to be important for recombination of homologous DNA sequences in this bacterium. Herein, we demonstrate that rrlA and rrlB code for two small proteins that participate in a feed-forward loop essential for sigma(20) function. In addition, we identify novel genes regulated by sigma(20) and show that several non-coding regions, which function as a reservoir for the generation of antigenic diversity, are also activated by this alternative sigma factor. Finally, we reveal that M. genitalium cells can transfer DNA horizontally by a novel mechanism that requires RecA and is facilitated by sigma(20) overexpression. This DNA transfer system is arguably fundamental for persistence of M. genitalium within the host since it could facilitate a rapid dissemination of successful antigenic variants within the population. Overall, these findings impose a novel conception of genome evolution, genetic variation and survival of M. genitalium within the host.