Date:
Location:
Abstract:
The RNA World hypothesis, which posits that RNA existed before the advent of DNA and proteins, remains a popular and influential hypothesis. However, despite decades of effort, origins of life researchers are still lacking a plausible prebiotic synthesis for RNA. Persistent challenges include nucleobase selection, nucleoside bond formation, and nucleotide polymerization. We are investigating the possibility that RNA was preceded by a polymer that would have assembled more easily than RNA (i.e., pre-RNA), being comprised of different nucleobases and, perhaps, a different backbone. In support of this hypothesis, recent experiments have revealed that alternative nucleobases can self-assemble in water and readily form nucleosides with ribose, two properties not observed with the nucleobases of extant RNA. A possible prebiotic mechanism for RNA replication, or its ancestral polymer, will also be discussed.