Caulimoviridae (Plant Pararetroviruses)

Abstract

Family Caulimoviridae comprises seven genera of plant viruses whose members replicate by reverse transcription and whose virions contain double‐stranded deoxyribonucleic acid . In a recent survey of the international scientific community, Cauliflower mosaic virus (CaMV), the type species of the family, was ranked sixth in the world in a list of the most scientifically or economically important plant viruses. This notoriety is due purely to the major conceptual advances that have been made in plant virology using CaMV as a model pathogen. However, several relatively lesser known viruses in the family, such as Rice tungro bacilliform virus and Cacao swollen shoot virus , are very serious constraints to crop production in tropical regions of the world. In this article, information on the taxonomy, replication cycle, vector transmission, epidemiology and disease management of this important group of plant viruses is summarised. Key Concepts: The Caulimoviridae is the only family of plant viruses with a double‐stranded deoxyribonucleic acid (dsDNA) genome, and in common with all viral retroelements, incorporates a reverse transcription step in the replication cycle. Cauliflower mosaic virus is the type species of the family, and has been a very important model plant virus for elucidating fundamental aspects of virus replication, cell‐to‐cell movement and aphid transmission. Members of the Caulimoviridae are most prominent in tropical regions, where they cause serious diseases such as rice tungro, cacao swollen shoot and banana streak disease. The most important component of a control programme for these viruses is to reduced inoculum levels by using clean planting material, avoiding overlapping crops, and removing diseased plants and alternative hosts of the virus. In some host species, infection can arise as a consequence of activation of viral DNA that is integrated in the nuclear genome of the plant.

Thermal stress modifies the marine sponge virome

“…). Members of the Retroviridae family have previously only been reported to infect vertebrate hosts (Hayward, ), and members of the Caulimoviridae infect plants (Geering, ), hence the host range of these viral contigs within the sponge holobiont is unclear. However, there is ongoing debate regarding the origin of the Retroviridae family, a close relative of the Metaviridae family, which has a much broader reported eukaryotic host range (Hayward, ).…”

Ortervirales: New Virus Order Unifying Five Families of Reverse-Transcribing Viruses

“…This broad distribution suggests the ancient origin(s) of these viruses, possibly concomitant with the emergence of eukaryotes (3). Reverse-transcribing viruses include prominent human pathogens, such as human immunodeficiency viruses 1 and 2 (HIV-1/2) and hepatitis B virus, as well as plant pathogens that cause considerable economic losses (4).…”

Infectivity of an Infectious Clone of Banana Streak CA Virus in A-Genome Bananas (Musa acuminata ssp.)

“…BSVs are members of the genus Badnavirus, family Caulimoviridae which have a doublestranded, circular DNA genome of about 7-9 kbp typically containing three open reading frames (ORFs) [4]. ORF 3 encodes a large polyprotein of~200 kDa that is processed into several mature functional proteins.…”