The Root of the Universal Tree of Life Inferred from Anciently Duplicated Genes Encoding Components of the Protein-Targeting Machinery

  title={The Root of the Universal Tree of Life Inferred from Anciently Duplicated Genes Encoding Components of the Protein-Targeting Machinery},
  author={Simonetta Gribaldo and Piero Cammarano},
  journal={Journal of Molecular Evolution},
Abstract. The key protein of the signal recognition particle (termed SRP54 for Eucarya and Ffh for Bacteria) and the protein (termed SRα for Eucarya and Ftsy for bacteria) involved in the recognition and binding of the ribosome SRP nascent polypeptide complex are the products of an ancient gene duplication that appears to predate the divergence of all extant taxa. The paralogy of the genes encoding the two proteins (both of which are GTP triphosphatases) is argued by obvious sequence… 

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Root of the universal tree of life based on ancient aminoacyl-tRNA synthetase gene duplications.

  • J. R. BrownW. Doolittle
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1995
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