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DNA binding by the Methanothermobacter thermautotrophicus Cdc6 protein is inhibited by the minichromosome maintenance

Rajesh Kasiviswanathan1, Jae-Ho Shin, Zvi Kelman

  • 1University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology, 9600 Gudelsky Drive, Rockville, MD 20850, USA.

Journal of Bacteriology
|June 3, 2006
PubMed

Insights

Cdc6 proteins from Methanothermobacter thermautotrophicus bind both single- and double-stranded DNA. Interactions with minichromosome maintenance (MCM) helicase mutants inhibit this DNA binding activity, revealing a regulatory mechanism.

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Archaeal Biology

Background:

  • Cdc6 proteins are essential for DNA replication initiation in various organisms.
  • Previous studies demonstrated double-stranded DNA binding by Cdc6 from Methanothermobacter thermautotrophicus.

Purpose of the Study:

  • To investigate the DNA binding capabilities of Methanothermobacter thermautotrophicus Cdc6 proteins.
  • To determine the effect of minichromosome maintenance (MCM) helicase interaction on Cdc6 DNA binding.

Main Methods:

  • Biochemical assays to assess DNA binding activity.
  • Utilizing minichromosome maintenance (MCM) helicase mutant proteins.

Main Results:

  • Methanothermobacter thermautotrophicus Cdc6 proteins exhibit binding to single-stranded DNA in addition to double-stranded DNA.
  • The interaction between MCM helicase mutants and Cdc6 proteins was found to inhibit the DNA binding activity of Cdc6.

Conclusions:

  • Cdc6 proteins possess broader DNA binding specificity than previously known.
  • MCM helicase plays a regulatory role in modulating Cdc6 DNA binding activity, suggesting a mechanism for controlling DNA replication initiation.

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