July 1, 2007 (Vol. 27, No. 13)
Strong Points: Unusual, but useful database info
Weak Points: Nothing significant
Base pairs are at the heart of molecular biology information. Recognized ever since their discovery by Watson and Crick in 1953, the base pair provides, among other things, rules for copying DNA, transcribing RNA, identifying proper tRNAs in translation, setting splice junctions, and more. A less-discussed subtopic about base pairs is that (gasp!) they don’t all form according to Watson-Crick rules. RNAs are the most common offenders due to the unusual pairings made possible with ‘U’ that aren’t possible with ‘T’ and the fact that RNA can’t form the ‘B’ structure common to DNA. Mismatches in RNA are not uncommon due to stabilizing base pairings on opposite sites of mismatches combined with the lack of proof reading or mismatch repair of RNAs. Tracking these changes is the Non-canonical Base Pair Database, which, though it is a work in progress, has over 1,750 occurrences of mismatches in RNA. Originally published in Nucleic Acids Research, the database is a gold mine for researchers.