Comovirinae

Comovirinae

3D structure of Cowpea Mosaic Virus, a member of the Comovirinae.

Comovirinae is a subfamily of viruses within the family Secoviridae. These viruses are known to infect plants, causing a variety of diseases that can significantly impact agricultural productivity. The subfamily includes several genera, with the most notable being Comovirus, Fabavirus, and Nepovirus.

Taxonomy

The Comovirinae subfamily is classified under the order Picornavirales. It comprises three genera:

• Comovirus: This genus includes viruses such as the Cowpea mosaic virus (CPMV), which is a well-studied model for plant virus research.
• Fabavirus: Known for infecting a wide range of host plants, including legumes and cucurbits.
• Nepovirus: This genus includes viruses that are often transmitted by nematodes and can cause significant damage to crops like grapes and strawberries.

Structure

Viruses in the Comovirinae subfamily are non-enveloped and have an icosahedral capsid. The capsid is composed of 60 copies of a single protein, forming a structure that is approximately 28 nm in diameter. The genome is bipartite, consisting of two single-stranded, positive-sense RNA molecules.

Genome

The genome of Comovirinae viruses is divided into two RNA segments:

• RNA-1: Encodes proteins involved in replication, including the RNA-dependent RNA polymerase.
• RNA-2: Encodes proteins that form the capsid and are involved in cell-to-cell movement.

Transmission

Comovirinae viruses are primarily transmitted through mechanical means, such as contact between plants or through agricultural practices. Some members of the subfamily, particularly those in the Nepovirus genus, are also transmitted by nematodes.

Symptoms

Infected plants may exhibit a range of symptoms, including mosaic patterns on leaves, stunted growth, and reduced yield. The severity of symptoms can vary depending on the virus species, the host plant, and environmental conditions.

Economic Impact

The diseases caused by Comovirinae viruses can lead to significant economic losses in agriculture. For example, the Cowpea mosaic virus affects legume crops, which are important for food security and soil health.

Related pages

• Secoviridae
• Picornavirales
• Plant virus
• Cowpea mosaic virus