Structure of the Parallel Duplex of Poly(A) RNA: Evaluation of a 50 Year‐Old Prediction

The other double helix: The molecular structure of double-stranded poly(rA) was predicted in 1961, but it has only now been confirmed. The crystal structure of the parallel double helix of (rA)11 obtained at physiological pH was solved using ab initio direct methods and refined to 1.0 Å resolution. The crystals have bound ammonium ions that are complexed by the RNA phosphates and adenine N1 atoms (see section of the structure). As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.