A Z-DNA sequence reduces slipped-strand structure formation in the myotonic dystrophy type 2 (CCTG) x (CAGG) repeat.

ABSTRACT: All DNA repeats known to undergo expansion leading to human neurodegenerative disease can form one, or several, alternative conformations, including hairpin, slipped strand, triplex, quadruplex, or unwound DNA structures. These alternative structures may interfere with the normal cellular processes of transcription, DNA repair, replication initiation, or polymerase elongation and thereby contribute to the genetic instability of these repeat tracts. We show that (CCTG) x (CAGG) repeats, in the first intron of the ZNF9 gene associated with myotonic dystrophy type 2, form slipped-strand DNA structures in a length-dependent fashion upon reduplexing. The threshold for structure formation on reduplexing is between 36 and 42 repeats in length. Alternative DNA structures also form in (CCTG)(58) x

SUBMITTER: Edwards SF 

PROVIDER: S-EPMC2651351 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature