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Updated: Jun 16, 2026

Immunostaining for DNA Modifications: Computational Analysis of Confocal Images
Published on: September 7, 2017
The phasevarion: phase variation of type III DNA methyltransferases controls coordinated switching in multiple genes
Yogitha N Srikhanta1, Kate L Fox, Michael P Jennings
1Institute for Glycomics, Griffith University, Gold Coast, Queensland, 4222, Australia.
Abstract:
In several host-adapted pathogens, phase variation has been found to occur in genes that encode methyltransferases associated with type III restriction-modification systems. It was recently shown that in the human pathogens Haemophilus influenzae, Neisseria gonorrhoeae and Neisseria meningitidis phase variation of a type III DNA methyltransferase, encoded by members of the mod gene family, regulates the expression of multiple genes. This novel genetic system has been termed the 'phasevarion' (phase-variable regulon). The wide distribution of phase-variable mod family genes indicates that this may be a common strategy used by host-adapted bacterial pathogens to randomly switch between distinct cell types.
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