DNA origami, make room: proteins can be bioengineered to fold up into three-dimensional architectures from one continuous strand, reports work published online this week in Nature Chemical Biology.

DNA origami, in which specific base pairing has been used to design a large variety of structures such as smiley faces, university logos, and boxes, has provided inspiration for scientists hoping to create ‘smart’ materials or simply explore our understanding of the forces that control molecular interactions. Protein assembly has also been studied, but these experiments have only utilized multiple short sequences interacting together to form larger structures.

Roman Jerala and colleagues show that longer protein sequences - in this case, a polypeptide containing 12 helices in a row - can be prompted to fold into designed structures based on specific pairing of the helices. The authors characterize their newly folded tetrahedron with several techniques, including showing that scrambled or shortened sequences no longer form the right shape. As the building blocks that make up proteins are more diverse than those in DNA, this study opens the door for entirely new architectures that may have new functions as well, such as cargo delivery or the creation of artificial catalytic sites.