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PubMed · 11566101

Origin recognition complex binding to a metazoan replication origin.

A K Bielinsky·H Blitzblau·E L Beall·M Ezrokhi·H S Smith·M R Botchan·S A Gerbi
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Abstract

The initiation of DNA replication in eukaryotic cells at the onset of S phase requires the origin recognition complex (ORC) [1]. This six-subunit complex, first isolated in Saccharomyces cerevisiae [2], is evolutionarily conserved [1]. ORC participates in the formation of the prereplicative complex [3], which is necessary to establish replication competence. The ORC-DNA interaction is well established for autonomously replicating sequence (ARS) elements in yeast in which the ARS consensus sequence [4] (ACS) constitutes part of the ORC binding site [2, 5]. Little is known about the ORC-DNA interaction in metazoa. For the Drosophila chorion locus, it has been suggested that ORC binding is dispersed [6]. We have analyzed the amplification origin (ori) II/9A of the fly, Sciara coprophila. We identified a distinct 80-base pair (bp) ORC binding site and mapped the replication start site located adjacent to it. The binding of ORC to this 80-bp core region is ATP dependent and is necessary to establish further interaction with an additional 65-bp of DNA. This is the first time that both the ORC binding site and the replication start site have been identified in a metazoan amplification origin. Thus, our findings extend the paradigm from yeast ARS1 to multicellular eukaryotes, implicating ORC as a determinant of the position of replication initiation.

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Adenosine TriphosphatasesAdenosine TriphosphateAnimalsBase SequenceBinding SitesDNA ReplicationDNA, ComplementaryDNA-Binding ProteinsDipteraInsect ProteinsMolecular Sequence DataOrigin Recognition ComplexReplication OriginJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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A K Bielinsky, H Blitzblau, E L Beall, M Ezrokhi, H S Smith, M R Botchan, S A Gerbi. 2001-09-18. Origin recognition complex binding to a metazoan replication origin.. https://doi.org/10.1016/s0960-9822(01)00444-4

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