Taxonomic Structure of the Subfamily
|
Subfamily |
Paramyxovirinae |
|
Genus |
Respirovirus |
|
Genus |
Rubulavirus |
|
Genus |
Morbillivirus |
Member species of the subfamily Paramyxovirinae have five to seven transcriptional elements. Members of different genera in the subfamily Paramyxovirinae exhibit some sequence relatedness between corresponding proteins, with NPM and L generally being the most conserved, F and HN somewhat less conserved, and P being poorly conserved although the unique region of V that is not shared with P is highly conserved. The division of this subfamily into the three genera is consistent with phylogenetic grouping based on amino acid sequence relationships, with the exception of NDV which falls between the genus Respirovirus and genus Rubulavirus (NDV mode of RNA editing is Repirovirus-like but doesn’t have a C protein yet its glycoproteins are Rubulavirus-like). Their nucleocapsids have diameters of 18 nm and a pitch of 5.5 nm, the length of the surface spikes is 8 nm. It has been observed that the genome length has to be a multiple of six nucleotides for efficient genome replication perhaps reflecting the precise packing of nucleotides by a nucleocapsid protein subunit. RNA editing of the P/V transcriptional element occurs for all members except HPIV-1. All members have a hemagglutinin activity.
|
| |