Creating the protein version of DNA base pairing

Specific interactions between molecules give rise to life. Nucleic acid is a good example: The pairing of adenine (A) to thymine (T) and cytosine (C) to guanine (G) ensures accurate passage of genetic materials over generations. Thanks to the programmable and modular nature of A-T/C-G base pairing, DNA has been repurposed to build nanoscopic smiley faces (1) and robots that sort molecular cargoes (2), giving rise to the field of DNA nanotechnology.