DNA structure and the Werner protein modulate human DNA polymerase delta-dependent replication dynamics within the common fragile site FRA16D.

ABSTRACT: Common fragile sites (CFS) are chromosomal regions that exhibit instability during DNA replication stress. Although the mechanism of CFS expression has not been fully elucidated, one known feature is a severely delayed S-phase. We used an in vitro primer extension assay to examine the progression of DNA synthesis through various sequences within FRA16D by the replicative human DNA polymerases delta and alpha, and with human cell-free extracts. We found that specific cis-acting sequence elements perturb DNA elongation, causing inconsistent DNA synthesis rates between regions on the same strand and complementary strands. Pol delta was significantly inhibited in regions containing hairpins and microsatellites, [AT/TA](24) and [A/T](19-28), compared with a control region with minimal secondary

SUBMITTER: Shah SN 

PROVIDER: S-EPMC2831333 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature