3 SMALL RIBOOLIGONUCLEOTIDES WITH SPECIFIC ARGININE SITES

Arginine-binding RNA motifs are important to protein-RNA interaction an perhaps also for Archean biochemistry. Selection-amplification was used to isolate three RNAs that are eluted by free arginine from an L-arginine affinity column (K(d) almost-equal-to 0.2-0.4 mM). The binding sites contain specific internal and bulge loops, whose sequences can include arginine coding triplets. Binding is highly specific for arginine, but all three motifs, like the self-splicing group I intron, also bind guanosine 5'-monophosphate. One site is stereoselective, somewhat preferring D-arginine.