Notes on Genus: Zeavirus


Type member: Maize necrotic streak virus


General Description

This is one of the genera in the family Tombusviridae. All the genera are morphologically similar, with icosahedral particles and small, (usually) monopartite ss RNA genomes. The genome organization resembles that of members of the genus Tombusvirus but the genome of 4.1kb is smaller and the coat protein is also smaller and lacks the protuding domain (thus resembling necroviruses).


Virions isometric (icosahedral), 28nm in diameter. 32 capsomeres per nucleocapsid.


Monopartite, linear, single stranded positive sense RNA about 4100 nucleotides long. 3' terminus has no poly(A) tract.

Genus Genomic Organization

The RNA is translated into five putative products, including a polymerase, a 27kDa coat protein translated from the larger of two subgenomic RNAs and two other products translated from the smaller subgenomic.

Type Member Genomic Organization

The RNA is translated into five putative products:
1. 30 kDaReplication protein
2. 89 kDaPolymerase readthrough
3. 27 kDaCoat protein, translated from subgenomic RNA1 (1607 nt)
4. 21 kDaMovement protein, translated from subgenomic RNA2 (781 nt)
5. 19 kDasilencing supressor, translated from subgenomic RNA2