An analysis of G-U base pair occurrence in eukaryotic 5S rRNAs

The structure-function relationship in RNA molecules is a key to understand ing of the expression of genetic information. Various types of RNA play cru cial roles at almost every step of protein biosynthesis. In recent years, i t has been shown that one of the most important structural elements in RNA is a wobble pair G-U. In this paper, we present for the first time an analy sis of the distribution of G-U pairs in eukaryotic 5S ribosomal RNAs. Inter estingly, the G-U pair in 5S rRNA species is predominantly found in two int rahelical regions of the stems I and V and at the junction of helix IV and loop A. The distribution of G-U pairs and the nature of adjacent bases sugg ests their possible role as a recognition site in interactions with other c omponents of protein biosynthesis machinery.