The molecular structure of Iresine viroid, a new viroid species from Iresine herbstii ('beefsteak plant')

J Gen Virol. 1996 Oct;77 ( Pt 10):2631-5. doi: 10.1099/0022-1317-77-10-2631.


A viroid was isolated from Iresine herbstii plants using the bidirectional PAGE method for analysis of small circular RNA molecules. The viroid was transmitted to viroid-free Iresine herbstii plants of the cultivar 'Aureoreticulata' by mechanical inoculation. Infected plants did not develop any symptoms. The new viroid species has been named Iresine viroid (IrVd). It is a member of the potato spindle tuber viroid group and consists of 370 nucleotides, 227 G+C, 143 A+U (GC content, 61.4%). The most stable rod-like secondary structure of this viroid has 86 G:C, 34 A:U and 12 G:U base pairs with a minimum free energy of -153.4 kcal/mol (-641.2 kJ/mol). The sequence and the position of the terminal conserved region (TCR) within the rod-like secondary structure of IrVd differ from the other known TCRs. The structure of the left terminal domain of IrVd may reflect the result of an intramolecular RNA recombination event.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Plant Viruses / genetics*
  • Plant Viruses / pathogenicity
  • Plants / virology*
  • Polymerase Chain Reaction
  • RNA, Viral*
  • Viral Proteins / analysis
  • Viroids / genetics*
  • Viroids / pathogenicity


  • RNA, Viral
  • Viral Proteins

Associated data

  • GENBANK/X95734