Thorsten Allers

Life without DNA replication origins - Thorsten Allers (University of Nottingham)

4:00pm - 5:00pm / Tuesday 6th November 2018 / Venue: Lecture Theatre 1 Life Sciences Building
Type: Seminar / Category: Research / Series: BEEM Seminar
  • Suitable for: Staff and students with an interest in Behaviour, Evolution, Ecology and Microbiology
  • Admission: Free Event
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DNA replication is initiated at specific chromosomal sites called origins, which serve as binding sites for proteins that recruit the replicative enzymes. Replication origins are assumed to be an essential part of the DNA replication apparatus but we have shown that in the archaeon Haloferax volcanii, life without origins is not only possible but highly efficient.
The replication enzymes found in archaea and eukaryotes differ fundamentally from those in bacteria. If homologous recombination is an ancestral process that predates the split between bacteria, archaea and eukaryotes, and the evolution of their different machineries for DNA replication, could it have been used to initiate replication in the last common ancestor?

We have shown that in the archaeon Haloferax volcanii, deletion of all chromosomal origins leads to the initiation of all DNA replication by homologous recombination. If homologous recombination alone can efficiently initiate the replication of an entire cellular genome, what purpose do replication origins serve and why they have evolved?