tRNA sequences can assemble into a replicator

Can replication and translation emerge in a single mechanism via self-assembly? The key molecule, transfer RNA (tRNA), is one of the most ancient molecules and contains the genetic code. Our experiments show how a pool of oligonucleotides, adapted with minor mutations from tRNA, spontaneously formed molecular assemblies. They replicated information autonomously using only reversible hybridization under thermal oscillations. A pool of cross-complementary hairpins self-selected by agglomeration and sedimented under gravity. The metastable DNA hairpins bound to a template, consisting of one half of the hairpin assembly, and then interconnected by hybridization. Thermal oscillations separated replicates from their templates and drove an exponential, cross-catalytic replication. The molecular assembly could encode and replicate binary sequence information and reach a fidelity of 90 % per nucleotide. This mechanism of a replicating self-assembly of tRNA-like sequences indicates that the translation to proteins could be linked closer to molecular replication than previously thought