Notes on Genus: Hemivirus

variable ovoid or spheroid

Type member: Drosophila melanogaster copia 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 (distinct phylogenetic lineages) in the retroelement family Pseudoviridae. DNA synthesis is primed by a half t-RNA molecule, hence the name (from the Greek hemi = half).

Morphology

Virus-like particles (VLPs) are poorly studied but seem to be non-enveloped, ovoid or spheroid in shape and 60-80 nm in diameter.

Genome

The major molecule is a positive sense ssRNA transcript of 4.5-6.5 kb flanked by Long Terminal Repeats (LTRs).

Genus Genomic Organization

The two major genes gag and pol are produced either from a single ORF or from 2 ORFs (either by ribosomal frameshift or via a spliced mRNA). As in other genera of the family, the pol contains protease (PR), integrase (IN) and reverse transcriptase (RT) domains in that order.

Type Member Genomic Organization

There is a single gag-pol ORF of 163 kDa. The gag is translated from a spliced mRNA.