Highly flexuous, naked nucleocapsids about 3 to 4 nm in diameter, forming open circles.
Segmented negative-stranded RNA linear genome
Contains 3 to 4 segments coding for up to seven proteins.
The viral RNA dependent RNA polymerase (L) binds to a promoter on each encapsidated segment, and transcribes a messenger RNA. Translational frameshift may occur on RNA-4 mRNA.