Fig. 3: Templated synthesis and release of active hammerhead ribozyme.
From: Ribozyme-mediated RNA synthesis and replication in a model Hadean microenvironment
a sunY catalyzes template-dependent ligation of the hammerhead ribozyme (HH-min, red) from the three RNA substrates (HH1-3, red). Local variations in pH and salt concentration cause strand separation, releasing ligated HH-min, which can then bind to and cleave its substrate (blue). b Ligated HH-min (red, Cy5) was observed in both the non-equilibrium and isothermal environments after 2 h of incubation. Formation of cleaved hammerhead substrate (HH-sub, blue, FAM) was observed only after incubation under non-equilibrium (AWI) conditions. Control experiments without sunY ribozyme exhibited no HH-min assembly or HH-sub cleavage, demonstrating that the combined unligated HH-min fragments HH1-3 have no residual RNA-cleavage activity. The isothermal control also showed no activity. Individual gel lanes (outlined with dotted lines) have been rearranged for clarity. c Bar graph showing the calculated yields of HH-sub cleavage after 2 h and 4 h in the AWI-system and under isothermal control conditions. Data are presented as mean values ± SEM. Black circles represent the values from independent replicates with n = 10 for 2 h incubation and n = 4 for 4 h incubation. Source data are provided as a Source Data file.
