Notes on Genus: Metapneumovirus

enveloped spheres
enveloped spheres

Type member: Avian metapneumovirus

Contents

General Description

The genus Metapneumovirus is one of nine genera in the family Paramyxoviridae and contains viruses with 8 transcriptional elements. It is named after the Greek meta = after and pneuma = breath.

Morphology

Virions pleomorphic but usually spherical, enveloped, 150 nm in diameter or larger with spike-like projections.

Genome

Monopartite single-stranded negative sense RNA of about 13-14 kb. There is no genome-linked protein (VPg) at the 5'-terminus nor a 3'-polyA tail.

Genus Genomic Organization

There are 8 transcriptional elements (mRNA species). Their major ORFs are listed here in their order on the template strand - i.e. from 3' to 5' with respect to the virion strand:
1    N43 kDa Coat protein (nucleocapsid)
2P 32 kDa Phosphoprotein
3M28 kDa Matrix protein
4F 58 kDa Fusion protein: glycosylated envelope protein
5M2   8/21 kDa Transcription processivity factor; two possible ORFs have been identified
6SH19-21 kDa Small hydrophobic membrane protein
7G26-64 kDa Glycoprotein attachment protein
8L 213-231 kDa Polymerase

Type Member Genomic Organization

There are 8 transcriptional elements (mRNA species). Their major ORFs are listed here in their order on the template strand - i.e. from 3' to 5' with respect to the virion strand:
1    N43 kDa Coat protein (nucleocapsid)
2P 32 kDa Phosphoprotein
3M28 kDa Matrix protein
4F 58 kDa Fusion protein: glycosylated envelope protein
5M2   8/21 kDa Transcription processivity factor; two possible ORFs have been identified
6SH21 kDa Small hydrophobic membrane protein
7G64 kDa Glycoprotein attachment protein
8L 213 kDa Polymerase