Related Experiment Video
Updated: Jul 28, 2026

Combining Analysis of DNA in a Crude Virion Extraction with the Analysis of RNA from Infected Leaves to Discover New Virus Genomes
Published on: July 27, 2018
The question of Citrus viroid IV as a cocadviroid
1Department of Plant Pathology, University of California, Riverside, California 92521-0122, USA. semancik@ucr.edu
Abstract:
It has been suggested that Citrus viroid IV (CVd-IV) be classified as a species within the genus Cocadviroid. This relationship was based on the presence of a terminal conserved hairpin (TCH) and absence of a terminal conserved region (TCR) as specific structural motifs in common with isolates of Coconut cadang-cadang viroid (CCCVd) as well as phylogenetic relationships with members of the genus Cocadviroid. Evidence is presented for a "vestigial" TCR in CVd-IV as well as the introduction of the terminal repeat region (TRR) motif and an alternative sequence analysis that suggests a closer phylogenetic relationship of CVd-IV to isolates of Citrus exocortis viroid (CEVd), a species within the genus Pospiviroid than to CCCVd. This position is further supported by the striking similarity of biological properties between CVd-IV and CEVd with the suggestion offered that biological evidence be considered for specific adjustments to any overall classification scheme for viroids.
More Related Videos
Related Concept Videos
Retrovirus Life Cycles
Introduction to Virus
Viruses with RNA Genomes
Subviral Agents
Inhibitors Of Virion Release
Inhibitors of Virion Maturation and Assembly

