Synthesis of linked triple helical DNAs possessing high affinity to triple helical DNA binding protein

The synthesis of triplexes possessing an anthraquinonyl group and composed of branched oligonucleotides (ONs) is described. Binding ability of a triplex-binding protein (MBP-LOR3ARF) to the triplexes was evaluated by an electrophoretic mobility shift assay (EMSA). It was found that the triplex, which has an anthraquinonecarbonyl group at the 5′-end of the third strand and is connected with the pentaerythritol linker, has greater affinity to the protein than an unmodified triplex.