A planarian nidovirus expands the limits of RNA genome size

@article{Saberi2018APN,
  title={A planarian nidovirus expands the limits of RNA genome size},
  author={Amir Saberi and Anastasia A. Gulyaeva and John L Brubacher and Phillip A. Newmark and Alexander E. Gorbalenya},
  journal={PLoS Pathogens},
  year={2018},
  volume={14}
}
RNA viruses are the only known RNA-protein (RNP) entities capable of autonomous replication (albeit within a permissive environment). A 33.5-kb nidovirus has been considered close to the upper size limit for such entities; conversely, the minimal cellular DNA genome is ~200 kb. This large difference presents a daunting gap for the transition from primordial RNP to contemporary DNA-RNP-based life. Whether or not RNA viruses represent transitional steps on the road to DNA-based life, studies of… 

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