Crystallographic studies of DNA and RNA.

Our knowledge of nucleic acid structure grew rapidly over the past decade with the determination to high resolution of larger structures of great biological significance. Advances in sample preparation, crystallization techniques, cryocrystallography, access to synchrotron radiation, and crystallographic software continue to accelerate the structure determination of nucleic acids. Crystallographic studies of DNA and RNA molecules share many considerations that we outline here. The application of crystallography to RNA is illustrated with the structure determination of the CUG repeat that is linked to type I myotonic dystrophy.