Base Pair

A base-pair consist of two nitrogenous bases interacting with each other via hydrogen bonds. It can be divided into two types; canonical base-pair and non-canonical base pair. In the canonical RNA Watson Crick pairing, adenine (A) forms a base-pair with uracil (U) while guanine (G) forms a base pair with cytosine (C). Alternate hydrogen bonding patterns between bases leads to the formation of non-canonical base pairs such as wobble GU base pair and Hoogsteen base-pair.

References:
i) Tinoco, Jr., R. F. Gesteland, J. F. Atkins, Eds. In The RNA World .1993. Cold
        Spring Harbor Laboratory Press, 603-607.
ii) Yurong X, Olson WK. 2009. BPS: a database of RNA base pair structures. Nucl.
        Acids Res 37: D83-D88