Notes on Family: Avsunviroidae

no particles
no particles


General Description

Viroids are small circular ssRNA molecules, which cause virus-like diseases of plants. There are two families and this one contains those (few) viroids that lack a central conserved region (CCR) and which have the ability to self-cleave in vitro and very probably in vivo, through hammerhead structures.


There are no virions.


Circular, ssRNA, consisting of 240-340 nucleotides. Secondary structure predictions suggest that they exist either as rod-shaped molecules with regions of base-pairing, interspersed with hairpin loops or adopt branched configurations. No peptides are encoded by the genome.

Genera in the Family

  • Avsunviroid (rod-shaped, unstable hammerhead ribozymes and 38% G+C)
  • Elaviroid (rod-shaped, stable hammerhead ribozymes and >50% G+C)
  • Pelamoviroid (branched, stable hammerhead ribozymes and >50% G+C)