Family Secoviridae Virus

The Secoviridae are a family of Group IV (positive-sense ssRNA) plant-infecting viruses in the order Picornavirales.
Several plant viruses share features with animal and human viruses of the family Picornaviridae, including a conserved structure of both the virus particle and the viral genome, expressing viral proteins by proteolytic cleavage of large polyproteins and encoding replication proteins with conserved sequence motifs. Members of the family Comoviridae were originally described as the only plant picorna-like viruses. Other plant picorna-like viruses were later discovered and classified in the family Sequiviridae. Sequiviridae and Comoviridae are related to each other in phylogenetic studies and share the common property of encoding specialized proteins to enable their movement in the plant. Recently, it was proposed to regroup plant picorna-like viruses into a single family termed ‘secoviridae’. The proposed family amalgamates the families Comoviridae and Sequiviridae, and incorporates other plant picorna-like viruses currently classified in the genera Sadwavirus and Cheravirus, and the proposed genus ‘Torradovirus’.
Key concepts:

    Many plant viruses are related to the animal and human picornaviridae and to other picorna-like viruses infecting algae and arthropods.
    A recent update in the taxonomy of plant picorna-like viruses has lead to the creation of the family ‘secoviridae’ which amalgamates the families Comoviridae and Sequiviridae as well as the existing genera Cheravirus, Sequivirus and the proposed genus ‘torradovirus’.
    Secoviridae share many common characteristics including having both similar virus particle structures and genomic organizations, and requiring a specialized protein to facilitate their movement within the host plant.
    Secoviridae produce their proteins in the form of large polyproteins that are cleaved at specific sites by a viral proteinase.
    Replication of the viral RNA occurs in large protein complexes in association with intracellular membranes from the host.
    Plant cells infected with secoviridae generally display tubular structures that are composed of the viral movement protein, contain virus-like particles and traverse the cell wall. These tubular structures are probably involved in the movement of the virus from cell to cell.
    Secoviridae can be transmitted through seeds and pollen or with the help of nematode or arthropod vectors and their spread in the field is largely dependent on their mode of transmission.

Posted in: Positive-Sense ssRNA Viruses ( Order Picornavirales )