Exocyclic amine of the conserved G.U pair at the cleavage site of the Tetrahymena ribozyme contributes to 5'-splice site selection and transition state stabilization.
Strobel SA, Cech TR. Exocyclic amine of the conserved G.U pair at the cleavage site of the Tetrahymena ribozyme contributes to 5'-splice site selection and transition state stabilization. Biochemistry. 1996 Jan 30; 35(4):1201-11.