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Updated: Aug 18, 2026

An Ecdysone Receptor-based Singular Gene Switch for Deliberate Expression of Transgene with Robustness, Reversibility, and Negligible Leakiness
Published on: May 7, 2018
The phasevarion: a genetic system controlling coordinated, random switching of expression of multiple genes
Yogitha N Srikhanta1, Tina L Maguire, Katryn J Stacey
1School of Molecular and Microbial Science and Institute for Molecular Bioscience, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
Abstract:
Several host-adapted bacterial pathogens contain methyltransferases associated with type III restriction-modification (R-M) systems that are subject to reversible, high-frequency on/off switching of expression (phase variation). To investigate the role of phase-variable expression of R-M systems, we made a mutant strain lacking the methyltransferase (mod) associated with a type III R-M system of Haemophilus influenzae and analyzed its phenotype. By microarray analysis, we identified a number of genes that were either up- or down-regulated in the mod mutant strain. This system reports the coordinated random switching of a set of genes in a bacterial pathogen and may represent a widely used mechanism.
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