Clusters of modular regulatory elements at DNA replication origins

Abstract

To study the specificity of eukaryotic origins of replication ( ori), we have isolated a fraction of mouse DNA enriched in replication initiation sequences ( RIS), and cloned and characterised some of these RIS. The sequences of three RIS were analysed for the presence of sequence elements common to other known eukaryotic ori. It was found that the three RIS were A + T rich and contained a number of sequence elements that may function in the initiation of DNA replication. The data support the idea that mammalian ori are organised from modular sequence elements.