Crystal structure of C-T-C-T-C-G-A-G-A-G. Implications for the structure of the Holliday junction.

The structure of the B-DNA decamer of sequence C-T-C-T-C-G-A-G-A-G shows a crossed arrangement of helices in the C2 crystal lattice. This is the fourth example of a crossed arrangement of B-DNA oligomers in a crystal, and in spite of the fact that each of these four crystallizes in a different lattice, all have nearly identical structures at the crossing contact. This ubiquitous crossing arrangement may be used to generate a structure for the Holliday junction that is fully consistent with the available physical data.