TY - JOUR TI - Emergence and diversification of a host-parasite RNA ecosystem through Darwinian evolution AU - Furubayashi, Taro AU - Ueda, Kensuke AU - Bansho, Yohsuke AU - Motooka, Daisuke AU - Nakamura, Shota AU - Mizuuchi, Ryo AU - Ichihashi, Norikazu A2 - Weigel, Detlef A2 - Szathmáry, Eörs A2 - Hogeweg, Paulien A2 - Hom, Erik VL - 9 PY - 2020 DA - 2020/07/21 SP - e56038 C1 - eLife 2020;9:e56038 DO - 10.7554/eLife.56038 UR - https://doi.org/10.7554/eLife.56038 AB - In prebiotic evolution, molecular self-replicators are considered to develop into diverse, complex living organisms. The appearance of parasitic replicators is believed inevitable in this process. However, the role of parasitic replicators in prebiotic evolution remains elusive. Here, we demonstrated experimental coevolution of RNA self-replicators (host RNAs) and emerging parasitic replicators (parasitic RNAs) using an RNA-protein replication system we developed. During a long-term replication experiment, a clonal population of the host RNA turned into an evolving host-parasite ecosystem through the continuous emergence of new types of host and parasitic RNAs produced by replication errors. The host and parasitic RNAs diversified into at least two and three different lineages, respectively, and they exhibited evolutionary arms-race dynamics. The parasitic RNA accumulated unique mutations, thus adding a new genetic variation to the whole replicator ensemble. These results provide the first experimental evidence that the coevolutionary interplay between host-parasite molecules plays a key role in generating diversity and complexity in prebiotic molecular evolution. KW - artificial cell KW - RNA replication system KW - self-replication system KW - in vitro evolution KW - coevolution KW - molecular parasite JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -