Basepairs involving WatsonCrick(W) edge of Cytosine and Sugar(S) edge of Uracil is shown. Highlighted examples are found from RNA crystal structures obtained from PDB.

Base pairs stabilized by N-H...N/O type hydrogen bonds only

Basepair

(type & Orientation)

*Frequency

Example

Hydrogen bonding atoms with their precursors

C:U +:S Trans

0

Optimized Model Structure

N3-O2...N3-C6

C6-C1'...N4-C5

* 1st and 2nd numbers in Frequency column represent the numbers of occurences as base pairs and as base triplets, respectively.