The sequence d(CGGCGGCCGC) self-assembles into a two dimensional rhombic DNA lattice

We report here the crystal structure of the partially self-complementary decameric sequence d(CGGCGGCCGC), which self assembles to form a four-way junction with sticky ends. Each junction binds to four others through Watson–Crick base pairing at the sticky ends to form a rhombic structure. The rhombuses bind to each other and form two dimensional tiles. The tiles stack to form the crystal. The crystal diffracted in the space group P1 to a resolution of 2.5 Å. The junction has the anti-parallel stacked-X conformation like other junction structures, though the formation of the rhombic net noticeably alters the details of the junction geometry.

► This is the first crystal structure of a four-way junction with sticky ends. ► Four junction structures bind to each other and form a rhombic cavity. ► Each rhombus binds to others to form ‘infinite’ 2D tiles. ► This is an example of bottom-up fabrication of a DNA nano-lattice.