caulimoviruses

Caulimoviruses are a genus of viruses in the family Caulimoviridae. These viruses infect plants and are known for their characteristic circular, double-stranded DNA genomes. The name "caulimovirus" is derived from Cauliflower Mosaic Virus (CaMV), the type species of the genus, which was one of the first plant viruses to be thoroughly studied. Caulimoviruses are transmitted by insects, specifically aphids, in a non-persistent manner, meaning the aphid can transmit the virus shortly after acquiring it but does not retain it for long periods.

The genome of a caulimovirus is typically around 8 kilobase pairs in length and is encapsidated within an isometric virus particle, usually about 50 nanometers in diameter. The virus replicates in the nucleus of infected plant cells, a distinguishing feature from many other plant viruses that replicate in the cytoplasm. Their replication cycle involves reverse transcription, a process typically associated with retroviruses, where RNA intermediates are used to synthesize DNA.

Caulimoviruses cause a range of symptoms in infected plants, which can include mosaic patterns, leaf curling, stunting, and reduced yield. While some species are host-specific, others can infect a broader range of plants. Their economic importance stems from their ability to cause significant damage to agricultural crops. Research into caulimoviruses has also been crucial for understanding plant virology and developing tools for plant molecular biology, as CaMV, in particular, has been widely used as a promoter in plant transformation vectors.