In vitro selection of N-peptide-binding RNA on a quartz-crystal microbalance to study a sequence-specific interaction between the peptide and loop RNA

On-the-spot RNA selection: N peptide or mutated N peptide was immobilized on a highly sensitive 27-MHz quartz-crystal microbalance, which was used as a monitoring and evaluation device for in vitro selection of RNA sequences that bind to these peptides (see figure). This method allowed the study of a sequence-specific interaction of the peptide with loop RNA in situ and without the use of labeling techniques and time-consuming separate binding assays.