The W. M. Keck Foundation supports a collaboration with Qi Zhang in the UNC Biochemistry and Biophysics Department and Abigail Knight in the UNC Chemistry Department. The effort is motivated by the recent validation in the tRNA acceptor stem of a palimpsest of the codon-anticodon interaction at the top of the tRNA acceptor stem.


This “overwritten manuscript” may reflect the origin of codon-directed peptide bond formation in tRNA minihelices containing only the acceptor stem and TψC loop.  Functional significance arises from the proposal of Schimmel et al of an operational RNA code in tRNA acceptor stems, in which ancestral tRNA minihelix ancestors were acylated with amino acids by ancestral tRNA synthetase urzymes. Prior work by David Liu’s group and others has established that base-pairing  to a DNA template can accelerate displacement chemistry of activated groups attached to complementary RNA adaptors.