Crystallographic characterization of CCG repeats.

ABSTRACT: CCG repeats are highly over-represented in exons of the human genome. Usually they are located in the 5' UTR but are also abundant in translated sequences. The CCG repeats are associated with three tri-nucleotide repeat disorders: Huntington's disease, myotonic dystrophy type 1 and chromosome X-linked mental retardation (FRAXE). In this study, we present two crystal structures containing double-stranded CCG repeats: one of an RNA in the native form, and one containing LNA nucleotides. Both duplexes form A-helices but with strands slipped in the 5' (native structure) or the 3' direction (LNA-containing structure). As a result, one of two expected C-C pairs is eliminated from the duplex. Each of the three observed C-C pairs interacts differently, forming either one weak H-bond or none. LNA n

SUBMITTER: Kiliszek A 

PROVIDER: S-EPMC3439926 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature