The oligoadenylate synthetase family: an ancient protein family with multiple antiviral activities

J Interferon Cytokine Res. 2011 Jan;31(1):41-7. doi: 10.1089/jir.2010.0107. Epub 2010 Dec 12.


The 2'-5' oligoadenylate synthetases (OAS) are interferon-induced antiviral enzymes that recognize virally produced dsRNA and initiate RNA destabilization through activation of RNase L within infected cells. However, recent evidence points toward several RNase L-independent pathways, through which members of the OAS family can exert antiviral activity. The crystal structure of OAS led to a novel insight into the catalytic mechanism, and revealed a remarkable similarity between OAS, Polyadenosine polymerase, and the class I CCA-adding enzyme from Archeoglobus fulgidus. This, combined with a variety of bioinformatic data, leads to the definition of a superfamily of template independent polymerases and proved that the OAS family are ancient proteins, which probably arose as early as the beginning of metazoan evolution.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • 2',5'-Oligoadenylate Synthetase / chemistry
  • 2',5'-Oligoadenylate Synthetase / genetics
  • 2',5'-Oligoadenylate Synthetase / metabolism*
  • Animals
  • Endoribonucleases / chemistry
  • Endoribonucleases / metabolism
  • Enzyme Activation
  • Gene Expression Regulation, Enzymologic*
  • Host-Pathogen Interactions
  • Humans
  • Interferons / metabolism*
  • Protein Conformation
  • RNA Stability
  • RNA, Double-Stranded / metabolism
  • RNA, Viral / metabolism
  • Virus Diseases / metabolism*
  • Virus Inactivation*


  • RNA, Double-Stranded
  • RNA, Viral
  • Interferons
  • 2',5'-Oligoadenylate Synthetase
  • Endoribonucleases
  • 2-5A-dependent ribonuclease