Atomic force microscopy of DNA in solution and DNA modelling show that structural properties specify the eukaryotic replication initiation site.

ABSTRACT: The replication origins (ORIs) of Schizosaccharomyces pombe, like those in most eukaryotes, are long chromosomal regions localized within A+T-rich domains. Although there is no consensus sequence, the interacting proteins are strongly conserved, suggesting that DNA structure is important for ORI function. We used atomic force microscopy in solution and DNA modelling to study the structural properties of the Spars1 origin. We show that this segment is the least stable of the surrounding DNA (9 kb), and contains regions of intrinsically bent elements (strongly curved and inherently supercoiled DNAs). The pORC-binding site co-maps with a superhelical DNA region, where the spatial arrangement of adenine/thymine stretches may provide the binding substrate. The replication initiation site (RIP)

SUBMITTER: Marilley M 

PROVIDER: S-EPMC2175326 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature