The phasevarion: Phase variation of type III DNA methyltransferases controls coordinated switching in multiple genes

Yogitha N. Srikhanta, Kate L. Fox, Michael P. Jennings

Research output: Contribution to journalReview ArticleResearchpeer-review

148 Citations (Scopus)


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.

Original languageEnglish
Pages (from-to)196-206
Number of pages11
JournalNature Reviews Microbiology
Issue number3
Publication statusPublished - 1 Mar 2010
Externally publishedYes

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