INVESTIGATION OF BASE-TRIPLE REQUIREMENTS FOR THE FORMATION OF AN INTRAMOLECULAR RNA TRIPLE HELIX

摘要

RNA triple helices occur when a single stranded region of RNA binds in the major groove of an RNA double helix through Hoogsteen interactions. To investigate the minimum number of base-triples required to form a stable intramolecular RNA triple helix, UV-spectroscopy was used to monitor the melting profiles of three RNA molecules with the potential to form four, five, and six base-triples. Intramolecular RNA triplexes containing five and six base-triples formed at pH values of 4.3 and 5.3, with and without 2 mM Mg~(2+) Formation of an intramolecular RNA triplex containing four base-triples was not observed under experimental conditions.