Hepatitis Delta Virus
Published Online: 15 NOV 2010
Copyright © 2001 John Wiley & Sons, Ltd. All rights reserved.
How to Cite
Taylor, J. M. 2010. Hepatitis Delta Virus. eLS.
- Published Online: 15 NOV 2010
Several viruses are important causes of acute and chronic infections of the human liver. Hepatitis delta virus (HDV) is a most unusual agent that is found only in association with Hepatitis B virus (HBV). HBV is a helper virus for HDV and provides the envelope proteins needed for the assembly of new HDV particles. Otherwise the replication of the HDV RNA (ribonucleic acid) genome is independent of HBV. HDV encodes only one protein, the delta antigen, a small basic RNA-binding protein, which is essential for genome replication. In the animal world, HDV is unique to infections of humans. However, HDV shows some intriguing similarities to plant viroids, which have RNA genomes even smaller than HDV, and encode no known proteins and have no helper viruses.
HDV uses HBV as a helper virus to achieve assembly of new virus particles.
HDV has a small single-stranded circular RNA genome.
During genome replication there arises the antigenome, an exact complement of the genome.
The HDV genome and antigenome are transcribed by redirection of a host RNA polymerase that normally acts on DNA templates.
Antigenomic HDV RNA sequences encode one small basic protein that is essential for genome replication
Site-specific RNA-editing on antigenomic RNA leads to the translation of a large delta antigen species, one that supports assembly via HBV envelope proteins.
The HDV RNA genome and its mode of replication show intriguing similarities to the plant viroid RNAs.
- RNA editing;