Tuning gene activity by inducible and targeted regulation of gene expression in minimal bacterial cells

Functional genomics studies in minimal mycoplasma cells enable unobstructed access to some of the most fundamental processes in biology. Conventional transposon bombardment and gene knockout approaches often fail to reveal functions of genes that are essential for viability, where lethality preclude...

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Detalles Bibliográficos
Autores: Martínez Mariscal, Ana M., Kakizawa, Shigeyuki, Hsu, Jonathan Y., Tanaka, Kazuki, Gonzalez-Gonzalez, Luis|||0000-0002-5853-967X, Broto, Alicia|||0000-0002-3275-8524, Querol Murillo, Enrique|||0000-0002-3658-3434, Lluch Senar, Maria, Piñero Lambea, Carlos, Sun, Lijie, Weyman, Philip D., Wise, Kim S., Merryman, Chuck, Tse, Gavin, Moore, Adam J., Hutchison, Clyde A., Smith, Hamilton O., Tomita, Masaru, Venter, J. Craig, Glass, John I., Piñol Ribas, Jaume|||0000-0002-9055-8934, Suzuki, Yo|||0000-0002-2797-6922
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:225194
Acceso en línea:https://ddd.uab.cat/record/225194
https://dx.doi.org/urn:doi:10.1021/acssynbio.8b00028
Access Level:acceso abierto
Palabra clave:Inducible promoters
Riboswitch
Tetracycline-mediated repression
Clustered regularly interspaced short palindromic repeats (CRISPR)
Mycoplasma
Functional genomics
Descripción
Sumario:Functional genomics studies in minimal mycoplasma cells enable unobstructed access to some of the most fundamental processes in biology. Conventional transposon bombardment and gene knockout approaches often fail to reveal functions of genes that are essential for viability, where lethality precludes phenotypic characterization. Conditional inactivation of genes is effective for characterizing functions central to cell growth and division, but tools are limited for this purpose in mycoplasmas. Here we demonstrate systems for inducible repression of gene expression based on clustered regularly interspaced short palindromic repeats-mediated interference (CRISPRi) in Mycoplasma pneumoniae and synthetic Mycoplasma mycoides, two organisms with reduced genomes actively used in systems biology studies. In the synthetic cell, we also demonstrate inducible gene expression for the first time. Time-course data suggest rapid kinetics and reversible engagement of CRISPRi. Targeting of six selected endogenous genes with this system results in lowered transcript levels or reduced growth rates that agree with lack or shortage of data in previous transposon bombardment studies, and now produces actual cells to analyze. The ksgA gene encodes a methylase that modifies 16S rRNA, rendering it vulnerable to inhibition by the antibiotic kasugamycin. Targeting the ksgA gene with CRISPRi removes the lethal effect of kasugamycin and enables cell growth, thereby establishing specific and effective gene modulation with our system. The facile methods for conditional gene activation and inactivation in mycoplasmas open the door to systematic dissection of genetic programs at the core of cellular life