[biorxiv.org] Life began with the emergence of a molecule that could replicate its own genetic material, a task plausibly mediated by an RNA-dependent RNA polymerase ribozyme.
Here, we present the structure of such a polymerase ribozyme, bound to RNA substrates comprising the template, primer, and nucleoside triphosphate (NTP) analog. The structure reveals how directed evolution shaped flanking elements around a highly conserved catalytic core derived from the ancestral class I ligase ribozyme.
Each element serves as a functional module, positioning the primer-template duplex and incoming NTP within the active site of the enzyme.
This emergent domain organization is remarkably similar to the “right hand” configuration of polymerase proteins, suggesting a common functional form for copying nucleic acids, regardless of biopolymer catalyst.
Structure of an RNA polymerase ribozyme replication complex, biorxiv.org
Astrobiology, Genomics, evolution,
