Secoviridae
Introduction '''''Secoviridae''''' is a family of viruses in the order ''Picornavirales''. Plants serve as natural hosts. There are 8 genera and 86 species in this family, one of which is unassigned to a genus. The family was created in 2009 with the grouping of families ''Sequiviridae'', now dissolved, and ''Comoviridae'', now subfamily ''Comovirinae'', along with the then unassigned genera ''Cheravirus'', ''Sadwavirus'', and ''Torradovirus''.
Taxonomy The family includes the following genera (-''virinae'' denotes subfamily and -''virus'' denotes genus):* ''Comovirinae''** ''Comovirus''** ''Nepovirus''** ''Fabavirus''* Unassigned to a subfamily:** ''Cheravirus''** ''Sadwavirus''** ''Sequivirus''** ''Stralarivirus''*** ''Strawberry latent ringspot virus''** ''Torradovirus''** ''Waikavirus''
Structure Viruses in ''Secoviridae'' are non-enveloped, with icosahedral geometries, and T=pseudo3 symmetry. The diameter is around 25-30 nm. Genomes are linear and segmented, bipartite, around 24-7kb in length. Genus  Structure  Symmetry  Capsid  Genomic arrangement  Genomic segmentation''Sequivirus''IcosahedralPseudo T=3Non-envelopedLinearMonopartite''Sadwavirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Nepovirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Fabavirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Comovirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Cheravirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Torradovirus''IcosahedralPseudo T=3Non-envelopedLinearSegmented''Waikavirus''IcosahedralPseudo T=3Non-envelopedLinearMonopartite
Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. The virus exits the host cell by tubule-guided viral movement.Plants serve as the natural host. Transmission routes are mechanical. Genus  Host details  Tissue tropism  Entry details  Release details  Replication site  Assembly site  Transmission''Sequivirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmMechanical inoculation: aphids; Mechanical inoculation: Cavariella aegopodii; Mechanical inoculation: Cavariella pastinacae''Sadwavirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmNematodes; mites; thrips''Nepovirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmNematodes; mites; thrips''Fabavirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmMechanical inoculation: aphids''Comovirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmMechanical inoculation: beetles''Cheravirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmNematodes; mites; thrips''Torradovirus''PlantsNoneViral movement; mechanical inoculationViral movementCytoplasmCytoplasmUnknown''Waikavirus''GramineaePhloem; phloem parenchyma; bundle sheathViral movementViral movementCytoplasmCytoplasmMechanical innocuation: aphids; mechanical innocuation: leafhoppers
Evolution The subfamily ''Comovirinae'' evolved  ~1,000 years ago with extant species diversifying between 50 and 250 years ago. This time period coincides with the intensification of agricultural practices in industrial societies.The mutation rate has been estimated to be 9.29×10−3 to 2.74×10−3 subs/site/year.
References
External links *  '''ICTV Online (10th) Report: ''Secoviridae''*  '''Viralzone''': ''Secoviridae''* UniProt Taxonomy