Role of SeqA and Dam in Escherichia coli gene expression: A global/microarray analysis

Anders Løbner-Olesen, M.G. Marinus, Flemming G. Hansen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    High-density oligonucleotide arrays were used to monitor global transcription patterns in Escherichia coli with various levels of Dam and SeqA proteins. Cells lacking Dam methyltransferase showed a modest increase in transcription of the genes belonging to the SOS regulon. Bacteria devoid of the SeqA protein, which preferentially binds hemimethylated DNA, were found to have a transcriptional profile almost identical to WT bacteria overexpressing Dam methyltransferase. The latter two strains differed from WT in two ways. First, the origin proximal genes were transcribed with increased frequency due to increased gene dosage. Second, chromosomal domains of high transcriptional activity alternate with regions of low activity, and our results indicate that the activity in each domain is modulated in the same way by SeqA deficiency or Dam overproduction. We suggest that the methylation status of the cell is an important actor in forming and/or maintaining chromosome structure.
    Original languageEnglish
    JournalProceedings of the National Academy of Sciences of the United States of America
    Volume100
    Issue number8
    Pages (from-to)4672-4677
    ISSN0027-8424
    DOIs
    Publication statusPublished - 2003

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