Notes on Family: Luteoviridae

icosahedra
icosahedra

Contents

General Description

This family is distinctive for its isometric particles of 25-30 nm diameter, monopartite genome and persistent, aphid transmission. The viruses often cause yellowing symptoms in their plant hosts.

Morphology

Virions are isometric (icosahedral), not enveloped, 25-30 nm in diameter, with 32 capsomeres per nucleocapsid. They contain 28 % nucleic acid.

Genomen

Monopartite, linear, single-stranded RNA, 5300-5800 nucleotides long. The 5'- terminus sometimes has a genome-linked protein (VPg).

Genera in the Family

  • Enamovirus (3 ORFs upstream of the coat protein; with VPg; lacking the functions for systemic movement, which are supplied by a second virus of the genus Umbravirus)
  • Luteovirus (2 ORFs upstream of the coat protein; without VPg; with systemic movement)
  • Polerovirus (3 ORFs upstream of the coat protein; with VPg; with systemic movement)