The potential for gene repair via triple helix formation
J. Clin. Invest. Michael M. Seidman, et al. 112:487 doi:10.1172/JCI19552 [Go to this article.]

Figure 3
Diagram of the purine motif for triple-helix formation. (a) Orientation of the third strand in the purine triple-helix motif. Note that the third strand is oriented antiparallel in terms of 5′ to 3′ direction with respect to the purine-rich strand of the duplex target. (b) Base triplets formed in the purine motif and illustration of the reverse Hoogsteen hydrogen bonds that stabilize triple-helix formation.