Pneumoviridae

Pneumoviridae (from Greek pneumo-, lung, -viridae, virus from Latin, poison, slimy liquid) is a new virus family in the order Mononegavirales. It was created in 2016 by elevating the now dissolved paramyxoviral subfamily Pneumovirinae. Natural hosts include humans, cattle, and rodents. There are currently 5 species in the Pneumoviridae family, divided between 2 genera (Metapneumovirus and Orthopneumovirus). Pneumoviruses are pleomorphic, capable of producing spherical and filamentous enveloped virions (virus particles) that vary in size from 150 to 200 nm in diameter. The nucleocapsid consisting of a protein shell and viral nucleic acids has a helical symmetry. Nucleocapsids have a diameter of 13.5 nm and a helical pitch of 6.5 nm. The genome is composed of negative-sense single-stranded RNA that is non-segmented. It is about 15kb in size, and encodes 11 proteins. A unique feature of the genome is the M2 gene, which encodes proteins M2-1 and M2-2. The Pneumoviridae M2-1 protein is distinctive, and no homologue has been found in any other virus families. It functions as a processivity factor for the virus RNA-dependent RNA polymerase, and promotes viral RNA synthesis. Viruses in this family are often associated with respiratory infections, and are transmitted through respiratory secretions. Pneumoviridae (from Greek pneumo-, lung, -viridae, virus from Latin, poison, slimy liquid) is a new virus family in the order Mononegavirales. It was created in 2016 by elevating the now dissolved paramyxoviral subfamily Pneumovirinae. Natural hosts include humans, cattle, and rodents. There are currently 5 species in the Pneumoviridae family, divided between 2 genera (Metapneumovirus and Orthopneumovirus). Pneumoviruses are pleomorphic, capable of producing spherical and filamentous enveloped virions (virus particles) that vary in size from 150 to 200 nm in diameter. The nucleocapsid consisting of a protein shell and viral nucleic acids has a helical symmetry. Nucleocapsids have a diameter of 13.5 nm and a helical pitch of 6.5 nm. The genome is composed of negative-sense single-stranded RNA that is non-segmented. It is about 15kb in size, and encodes 11 proteins. A unique feature of the genome is the M2 gene, which encodes proteins M2-1 and M2-2. The Pneumoviridae M2-1 protein is distinctive, and no homologue has been found in any other virus families. It functions as a processivity factor for the virus RNA-dependent RNA polymerase, and promotes viral RNA synthesis. Viruses in this family are often associated with respiratory infections, and are transmitted through respiratory secretions.