Computer-modeling origin of a simple genetic apparatus
AUTOR(ES)
Kuhn, Christoph
FONTE
The National Academy of Sciences
RESUMO
This computer simulation is based on a model of the origin of life proposed by H. Kuhn and J. Waser, where the evolution of short molecular strands is assumed to take place in a distinct spatiotemporal structured environment. In their model, the prebiotic situation is strongly simplified to grasp essential features of the evolution of the genetic apparatus without attempts to trace the historic path. With the tool of computer implementation confining to principle aspects and focused on critical features of the model, a deeper understanding of the model's premises is achieved. Each generation consists of three steps: (i) construction of devices (entities exposed to selection) presently available; (ii) selection; and (iii) multiplication of the isolated strands (R oligomers) by complementary copying with occasional variation by copying mismatch. In the beginning, the devices are single strands with random sequences; later, increasingly complex aggregates of strands form devices such as a hairpin-assembler device which develop in favorable cases. A monomers interlink by binding to the hairpin-assembler device, and a translation machinery, called the hairpin-assembler-enzyme device, emerges, which translates the sequence of R1 and R2 monomers in the assembler strand to the sequence of A1 and A2 monomers in the A oligomer, working as an enzyme.
