Induction of an ATP-polymerizing enzyme in TMV-infected tobacco and its homology to the human 2′-5′ a synthetase

Naamit Sher, Orit Edelbaum, Zehava Barak, Gideon Grafi, Yehuda Stram, Jacob Raber, Ilan Sela

Research output: Contribution to journalArticle

4 Scopus citations


Several reports have indicated that tobacco carries an enzyme (APE) that, in the presence of poly (rI):(rC), polymerizes ATP to oligoadenylates. This paper demonstrates that the tobacco APE system comprises several proteins (estimated sizes: 32, 42, 67, and 84±10% kD). Only one of these proteins (the "67-kD" form) binds to poly (rI):(rC). This APE form has been purified by affinity chromatography on a synthetic ds-RNA column. Four tobacco proteins, including the purified one, crossreact with antibodies against the human enzyme, 2′-5′ A synthetase. The ATP-binding capacity of some of these proteins has also been demonstrated. The amount of plant oligoadenylates obtained by polymerizing ATP with the purified APE form allows, for the first time, their direct analysis by TLC. The TLC analysis indicated that the oligomer produced by APE is not identical to the 2′-5′ oligoadenylate.

Original languageEnglish (US)
Pages (from-to)27-39
Number of pages13
JournalVirus Genes
Issue number1
Publication statusPublished - Jun 1990
Externally publishedYes



  • 2-5 A synthetase
  • interferon
  • TMV
  • tobacco

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Virology

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