Résumé
Group II introns are ubiquitous self-splicing ribozymes and retrotransposable elements evolutionarily and chemically related to the eukaryotic spliceosome, with potential applications as gene-editing tools. Recent biochemical, cellular, evolutionary, and structural data have captured the intron in multiple conformations at different stages of catalysis and folding at high-resolution. These studies have provided detailed mechanistic insight into group II intron splicing and analogies to the spliceosome, thus reinforcing the notion that these evolutionarily-related molecular machines share the same enzymatic strategy. Here, we review - also from a historical perspective - the significant milestones that have contributed to the molecular characterization of self-splicing group II introns, we describe their characteristics in an evolutionary, functional, and structural context, and we describe how future research on these important ribozymes can impact on RNA biology, RNA biochemistry, and RNA-directed therapy in the years to come.