Notes on Genus: Citrivirus

flexuous filaments
flexuous filaments

Type member: Citrus leaf blotch virus


General Description

The genus Citrivirus is one of is one of the genera in the family Betaflexiviridae. In genome organisation it particularly resembles the genus Trichovirus but has a much larger coat protein that is phylogenetically distinct and much more closely related to foveaviruses, together with longer virions. There are no known vectors. The name is from the type (and only) member Citrus leaf bloch virus.


Virions filamentous and flexuous, not enveloped, 960 nm long and 12 nm in diameter.


Monopartite, linear, single stranded, positive sense RNA, 8747 nucleotides long. The 3' terminus has a poly(A) tract and the 5' terminus has a methylated nucleotide cap.

Genus Genomic Organization

The genome is translated by means of 3 ORFs. The largest ORF (ORF1) is involved in replication, while ORF2 (putative movement protein) and ORF3 (coat protein) are expressed from subgenomic mRNAs. Unlike trichoviruses, the coat protein ORF does not overlap with that of the movement protein.

Type Member Genomic Organization

The genome is believed to be translated by means of three open reading frames:
  1. 227 kDa polyprotein: putative replicase
  2. 40 kDa Movement protein
  3. 41 kDa Coat protein