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bioRxiv · 10.1101/281147

Evidence of an Unusual Poly(A) RNA Signature Detected by High-throughput Chemical Mapping

Wellington-Oguri, R.·Fisker, E.·Wiley, M.·Zada, M.·Eterna Players,
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Abstract

Homopolymeric adenosine RNA plays numerous roles in both cells and non-cellular genetic material, and for lack of evidence to the contrary, it is generally accepted to form a random coil under physiological conditions. However, chemical mapping data generated by the Eterna Massive Open Laboratory indicates that a poly (A) sequence of length seven or more, at pH 8.0 and MgCl concentrations of 10 mM, develops unexpected protection to selective 2-hydroxyl acylation read out by primer extension (SHAPE) and dimethyl sulfate (DMS) chemical probing. This protection first appears in poly(A) sequences of length 7 and grows to its maximum strength at length ~10. In a long poly(A) sequence, substitution of a single A by any other nucleotide disrupts the protection, but only for the 6 or so nucleotides on the 5 side of the substitution. The authors are grateful for pre-publication comments; please use https://docs.google.com/document/d/14972Q36IDTYMglwMXTOrqd4P9orQ6-P3bPbCuITdv6A.

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Wellington-Oguri, R., Fisker, E., Wiley, M., Zada, M., Eterna Players,. 2018-04-30. Evidence of an Unusual Poly(A) RNA Signature Detected by High-throughput Chemical Mapping. https://doi.org/10.1101/281147

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