2-Aminoadenosine

2-Aminoadenosine is a modified adenine base and adenosine analog that stabilizes RNA duplexes and enhances template-directed nucleotide condensation reactions. 2-Aminoadenosine forms three hydrogen bonds with uracil to increase the melting temperature of hybrid strands, thereby stabilizing uracil-containing RNA duplexes^[1][2]. In Vitro:2-Aminoadenosine-containing antisense oligonucleotide (3 hours at 30°C) depletion of U5 snRNP abolishes pre-mRNA splicing activity in HeLa cell nuclear extracts, and this activity is recoverable via complementation with extracts depleted of other spliceosomal snRNPs^[1].
2-Aminoadenosine (0.1 M; 14 days at 0°C) increases U incorporation efficiency to 30% and enhances G incorporation efficiency in template-directed non-enzymatic oligonucleotide synthesis when substituted into a poly(CA) template^[2].
2-Aminoadenosine (0.025-0.1 M; 14 days at 0°C) maintains high G incorporation efficiency (91% for poly(C_2.9U₁) template, 64% for poly(C₁U₁) template) at reduced substrate concentrations, whereas adenosine-based substrates show drastically reduced G incorporation efficiency at lower concentrations^[2].