The dual role of autonomously replicating sequences as origins of replication and as silencers.

Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada.
Current Genetics (Impact Factor: 1.71). 08/2009; 55(4):357-63. DOI: 10.1007/s00294-009-0265-7
Source: PubMed

ABSTRACT Autonomously replicating sequences (ARSs) in Saccharomyces cerevisiae have been extensively characterized as both origins of DNA replication and as chromatin repressors/silencers. It has been conclusively shown that the origin and the silencer activities of ARS are substantially, but not entirely interchangeable and that they are modulated by position effects and chromatin environment. It remains unclear how these two quite divergent functions of ARS co-exist. This perspective focuses on recent advances, which have shown that slight differences in ARSs can modulate their affinity for origin recognition complex and their activity as silencers or origins.

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