RNA World and Ribozyme Engineering
QUESTION: RNA world – What is Ribozyme Engineering?ANSWER:In ribozyme engineering , engineers attempt to enhance the capacity of RNA catalysts in order to demonstrate the plausibility of the RNA world model. Ribozyme engineers attempt to show that linking enzymes called RNA ligases can acquire true polymerase function, making possible template-directed self-replication.
The irony, of course, is that ribozyme engineers who use an ‘irrational-design-approach’ encounter problems that they must use their intelligence to solve. The irrational-design approach tries to model a form of prebiotic natural selection to enhance the function of the ligases. Incremental improvements in the function of these enzymes are preserved, replicated, amplified, and then selected for further mutation and selection in hopes of eventually producing a polymerase capable of template-directed self-replication. But prior to the emergence of polymerases, nothing in nature would perform these critical steps. Without an enzyme which is capable of true self-replication, natural selection is not on the cards.
The ribozyme engineers have the foresight to see that ligase capacity -- in conjunction with the other capacities of true polymerases -- might enable self-replication to proceed. Therefore they select molecules with slightly enhanced ligase capacity. These molecules are then preserved and optimized. The investigators select RNA sequences informed by knowledge of the conditions necessary to actualize that future functions of template-directed self-replication. Since nature lacks such foresight, the ribozyme engineer supplies what nature doesn’t. The ‘randomization’ and ‘selection’ steps in ribozyme engineering have no realistic prebiotic analogues. Ribozyme engineering -- where RNA is necessarily synthesized by intelligent agents is, truly,
engineering.RNA world and Ribozyme Engineering - ConclusionWe can see that research in one context (ribozyme engineering) with its particular presuppositions and goals in view -- and with results presumably providing insight into one putative process of origins -- has in fact provided compelling evidence for a very different view. The procedures used in research on RNA catalysis reinforce the notion that intelligent design is indeed required for the production of molecular species that simply cannot form due to the natural chemical tendencies of the reacting substances themselves.