Notes on Genus: Metavirus

variable ovoid or spheroid

Type member: Saccharomyces cerevisiae Ty3 virus

Contents

Members of this Genus
General Description
Morphology
Electron Micrograph
Genome
Genus Genomic Organization
Genome Map
Type Member Genomic Organization
Curated Sequences

General Description

This is one of the genera in the retroelement family Metaviridae. Members have 1 or 2 ORFs and a genome of less than 6 kb. The name is from the Greek metathesis = transposition.

Morphology

Virus-like particles (VLPs) are poorly studied but seem to include irregular ovoid enveloped particles up to 100 nm in diameter and smaller non-enveloped particles.

Genome

Positive sense, ssRNA molecules, less than 6 kb long, flanked by Long Terminal Repeats (LTRs).

Genus Genomic Organization

Depending on the member, there is either one continuous ORF, or 2 in separate reading frames (gag and pol) and a frameshift to generate the pol. As in other genera of the family, the pol contains protease (PR), reverse transcriptase (RT) and integrase (IN) domains in that order.

Type Member Genomic Organization

There are 2 ORFs:
  1. gag: structural polyprotein of 36 kDa
  2. pol: polymerase of 146 kDa with protease (PR), reverse transcriptase (RT) and integrase (IN) domains