Crystal structure of actinomycin D bound to the CTG triplet repeat sequences linked to neurological diseases.

ABSTRACT: The potent anticancer drug actinomycin D (ActD) acts by binding to DNA GpC sequences, thereby interfering with essential biological processes including replication, transcription and topoisomerase. Certain neurological diseases are correlated with expansion of (CTG)n trinucleotide sequences, which contain many contiguous GpC sites separated by a single base pair. In order to characterize the binding of ActD to CTG triplet repeat sequences, we carried out heat denaturation and CD analyses, which showed that adjacent GpC sequences flanking a T:T mismatch are preferred ActD-binding sites, and that ActD binding results in a conformational transition to A-type structure. The structural basis of the strong binding of ActD to neighboring GpC sites flanking a T:T mismatch was provided by the cryst

SUBMITTER: Hou MH 

PROVIDER: S-EPMC137167 | biostudies-literature | 2002 Nov

REPOSITORIES: biostudies-literature