Evolution of Viruses With Single-Stranded Negative Sense RNA Genomes
The evolution of viruses with single-stranded negative-sense RNA genomes appears more
clear than that of their ss(+)sense and dsRNA counterparts. In fact, the phylogenetic affinities
of the families Paramyxoviridae, Rhabdoviridae and Filoviridae have been recognised by their
being grouped toether by the ICTV into the Order Mononegavirales, of viruses possessing
linear, non-segmented ssRNA(-) genomes with a similar gene order [3' non-translated region -
core proteins - envelope proteins - polymerase - 5' non-translated region], a single 3' promoter,
and helical nucleocapsids.
It is assumed that these virus families obviously descend from a common ancestor;
however, the sequence affinities of especially the polymerase genes but also the
nucleocapsid genes of viruses in the families Orthomyxoviridae and Bunyaviridae with the
Mononegavirales, indicate that a common ancestor for all ssRNA(-) viruses is not unlikely.
Virus Taxonomy - Sixth report of the International COmmittee on Taxonomy of viruses
(Murphy et al., Eds.). Springer-Verlag, Wien, 1995.
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