retrovirus

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retrovirus

 [ret´ro-vi″rus]
any member of a large family of RNA viruses that includes the lentiviruses and certain oncoviruses, given this name because they carry reverse transcriptase.
human endogenous r's (HERV) retroviruslike sequences found in the human genome, thought to constitute the remains of true retroviruses that were absorbed through evolution; at least one is thought to be linked to expression of tumor cells.

ret·ro·vi·rus

(ret'rō-vī'rŭs),
Any virus of the family Retroviridae.

Retroviruses are potent disease agents, but they have also served as invaluable research tools in molecular biology. In 1979, the molecular biologist Richard Mulligan used a genetically altered retrovirus to trigger the production of hemoglobin in vitro by monkey kidney cells. His technique for using retroviruses to import alien genes into cells has been widely adopted. Medical researchers have also explored retroviral transport as a means of gene therapy. However, evidence suggesting that retroviruses may play a role in carcinogenesis raises questions as to the safety of their use in gene therapy. see oncogene.

retrovirus

/ret·ro·vi·rus/ (ret´ro-vi″rus) a large group of RNA viruses that includes the leukoviruses and lentiviruses; so called because they carry reverse transcriptase.

retrovirus

(rĕt′rō-vī′rəs, rĕt′rə-vī′-)
n. pl. retrovi·ruses
Any of a family of viruses, many of which produce tumors, that contain RNA and reverse transcriptase, including HIV.

ret′ro·vi′ral adj.

retrovirus

[-vī′rəs]
Etymology: L, retro + virus
any of a family of ribonucleic acid (RNA) viruses containing the enzyme reverse transcriptase in the virion. The genetic information of the virus is stored in a molecule of single-stranded ribonucleic acid. After entering the target cell, the virus uses reverse transcriptase to direct the cell to make viral deoxyribonucleic acid (DNA). The DNA becomes integrated into the DNA of the host cell. Retroviruses are enveloped and assemble their capsids in the cytoplasm of the host cell. Retroviruses are used in laboratory research to import foreign DNA into a cell. They are transmitted by sexual contact with an infected person, through exposure to infected blood or blood products, and perinatally from an infected mother to the child. Human immunodeficiency virus (HIV1, HIV2), which causes acquired immunodeficiency syndrome, is a retrovirus. Other retroviruses include members of the Oncornaviridae family, such as human T cell lymphotropic virus type 1 (HTLV-1) and human T cell lymphotropic virus type 2 which cause adult T cell leukemia, hairy cell leukemia, tropical spastic paresis, and HTLV-1-associated myelopathy.

retrovirus

Virology An RNA virus that encodes reverse transcriptase so that its RNA can be transcribed into DNA in a host cell; modified retroviruses are used as vectors to introduce genes–or portions thereof–of interest into eukaryotic cells. See Cloning vector, DNA, Eukaryote, Gene, HIV, HTLV, Reverse transcriptase, RNA, Rous sarcoma virus, Spumavirus, Transciption, Virus.

ret·ro·vi·rus

(ret'rō-vī'rŭs)
Any virus of the family Retroviridae. A virus with RNA core genetic material; requires the enzyme reverse transcriptase to convert its RNA into proviral DNA.

retrovirus

A virus with a GENOME consisting of a single strand of RNA from which DUPLEX DNA is synthesized under the catalytic influence of an enzyme called reverse transcriptase. This is the reverse of the much more common DNA to RNA process. The AIDS virus HIV is a retrovirus.

retrovirus

an RNA VIRUS that infects animal CELLS and replicates by first being converted to double-stranded DNA, with the ENZYME REVERSE TRANSCRIPTASE. (Retroviruses are so called because the information flows from RNA to DNA.) The DNA copy of the RNA GENOME so formed integrates into the host's DNA. There is a number of groups of retroviruses, including the spumaviruses, for example the human foamy virus; the lentiviruses, for example HIV; and the oncoviruses (RNA tumour viruses) which are divided into A-type, B-type, C-type and D-type.

Retrovirus

A family of RNA viruses containing a reverse transcriptase enzyme which allows the viruses' genetic information to become part of the genetic information of the host cell upon replication.

ret·ro·vi·rus

(ret'rō-vī'rŭs)
Any virus of the family Retroviridae. A virus with RNA core genetic material; requires the enzyme reverse transcriptase to convert its RNA into proviral DNA.

retrovirus (ret´rōvīrus),

n a virus containing ribonucleic acid rather than deoxyribonucleic acid.

retrovirus

a member of the family Retroviridae.

defective retrovirus
a virus unable to replicate independently; commonly the result of loss of part of the envelope gene when leukosis viruses acquire an oncogene. Propagation is achieved by coinfection with a leukosis virus able to provide the envelope for the defective virus.
endogenous retrovirus
one transmitted in germ-line DNA from an infected parent to offspring.
exogenous retrovirus
one transmitted horizontally.
rapidly transforming retrovirus
characterized by rapid oncogenesis attributable to the v-onc gene which they carry.
slowly transforming retrovirus
weakly oncogencic after a long incubation period. They do not carry the v-onc gene.