|
Type Species |
(HIV-1) |
Virions have a distinctive morphology with a bar, or cone-shaped core (nucleoid). Viruses assemble at the cell membrane. Proteins Mr are: MA ± 17 
103; CA ± 24 103; NC ± 7-11 103; PR ± 14 103; RT ± 66 103; DU (in all except the primate lentiviruses); IN ± 32 103; SU ± 120 103; TM ± 41 103. The genome is about 9.3 kb in size (one monomer); its organization is illustrated in Figure 7.
In addition to the structural gag, pro, pol, and env genes, there are additional genes, depending on the virus (e.g., for Human immunodeficiency virus 1 (HIV-1): vif, vpr, vpu, tat, rev, nef) whose products are involved in regulation of synthesis and processing of virus RNA and other replicative functions. Most are located 3
to gag-pro-pol and, at least in part, 5 to env, one (nef in HIV-1) is 3 to env. For other viruses there may be additional non-structural genes (e.g., vpx in HIV-2). The tRNA primer is tRNALys 1,2. The LTR is about 600 nts long, of which the U3 region is 450 nts, the R sequence 100 nts and the U5 region some 80 nts in size.
The viruses in the genus include exogenous viruses (horizontal and vertical transmission) of humans and many other mammals. No related endogenous viruses are known. The primate lentiviruses are distinguished by the use of a chemokine receptor and the CD4 protein as receptor and the absence of DU. Some groups have cross-reactive Gag antigens (e.g., the ovine, caprine and feline lentiviruses). Viruses related to Feline immunodefficiency virus (FIV) have been isolated from other large felids (eg. the Puma lentivirus), and antibodies to Gag antigens in lions and other large felids indicate the existence of other viruses related to FIV and the ovine/caprine lentiviruses.
The viruses are associated with a variety of diseases including immunodeficiencies, neurological disorders, arthritis, and others. No oncogene-containing member of this genus has been isolated.
List of Species Demarcation Criteria in the Genus
The list of species demarcation criteria is:
|
Differences in genome and gene product sequences, |
|
Differences in antigenic properties, |
|
Differences in natural host range, |
|
Differences in pathogenicity. |
Five groups of lentiviruses can be clustered on the basis of the hosts they infect (primates, sheep and goats, horses, cats, and cattle). Within the Primate Lentivirus Group, HIV-1 is distinguished from HIV-2, for example, primarily on the basis of sequence divergence that exceeds 50% and the presence in HIV-2 of the vpx gene. There is limited cross-reactivity in ELISA tests based on Gag components but essentially none in those based on env gene products.
Official virus species names are in italics. Tentative virus species names, alternative names ( ), strains or serotypes are not italicized. Virus names, genome sequence accession numbers [ ], and assigned abbreviations ( ) are:
|
Bovine lentivirus group: | ||
|
Bovine immunodeficiency virus |
[M32690] |
(BIV) |
|
Equine lentivirus group: | ||
|
Equine infectious anemia virus |
[M16575] |
(EIAV) |
|
Feline lentivirus group: | ||
|
Feline immunodeficiency virus (Petuluma) |
[M25381] |
(FIV-P) |
|
Feline immunodeficiency virus (Oma) |
[FIU56928] |
(FIV-O) |
|
Puma lentivirus (PLV-14) |
[PLU03982] |
(PLV) |
|
Ovine/caprine lentivirus group: | ||
|
Caprine arthritis encephalitis virus |
[M33677] |
(CAEV) |
|
Visna/maedi virus (strain 1514) |
[M60609, M60610] |
(VISNA) |
|
Primate lentivirus group: | ||
|
Human immunodeficiency virus 1 |
(HIV-1) | |
|
Several genomic clades of HIV-1 are recognized. Examples include: | ||
|
Clade A | ||
|
U455 |
[M62320] |
(HIV-1.U455) |
|
Clade B | ||
|
ARV-2/SF-2 |
[K02007] |
(HIV-1.ARV-2/SF-2) |
|
BRU (LAI) |
[K02013] |
(HIV-1. BRU (LAI)) |
|
HXB2 |
[K03455] |
(HIV-1.HXB2) |
|
RF |
[M17451] |
(HIV-1.RF) |
|
MN |
[M17449] |
(HIV-1.MN) |
|
Clade C | ||
|
ETH2220 |
[U46016] |
(HIV-1.ETH2220) |
|
Clade D | ||
|
NDK |
[M27323] |
(HIV-1.NDK) |
|
ELI |
[X04414] |
(HIV-1.ELI) |
|
Clade F | ||
|
93BR020 |
[AF005494] |
(HIV-1.93BR020) |
|
Clade H | ||
|
90CR056 |
[AF0055494] |
(HIV-1.90CR056) |
|
Clade O | ||
|
ANT70 |
[L20587] |
(HIV-1.ANT70) |
|
Human immunodeficiency virus 2 |
(HIV-2) | |
|
Several genomic clades of HIV-2 are recognized. Examples include: | ||
|
Clade A: | ||
|
BEN |
[M30502] |
(HIV-2.BEN) |
|
ISY |
[J04498] |
(HIV-2.ISY) |
|
ROD |
[M15390] |
(HIV-2.ROD) |
|
ST |
[M31113] |
(HIV-2.ST) |
|
Clade B: | ||
|
D205 |
[X61240] |
(HIV-2.D205) |
|
EHOA |
[U27200] |
(HIV-2.EHOA) |
|
UC1 |
[L07625] |
(HIV-2.UC1) |
|
Simian immunodeficiency virus |
(SIV) | |
|
African Green Monkey (agm) SIVs | ||
|
African green monkey TYO |
[X07805] |
(SIV-agm.TYO) |
|
African green monkey 155 |
[M29975] |
(SIV-agm.155) |
|
African green monkey 3 |
[M30931] |
(SIV-agm.3) |
|
African green monkey gr-1 |
[M58410] |
(SIV-agm.gr) |
|
African green monkey Sab-1 |
[U04005] |
(SIV-agm.sab) |
|
African green monkey Tan-1 |
[U58991] |
(SIV-agm.tan) |
|
chimpanzee SIV |
[X52154] |
(SIV-cpz) |
|
mandrill SIV |
[M27470] |
(SIV-mnd) |
|
red capped mangabey SIV |
[AF028607](pol) |
(SIV-rcm) |
|
sooty mangabey SIV-H4 |
[X14307] |
(SIV-sm) |
|
[M195499] |
(SIV-mac) | |
|
[M32741] |
(SIV-mne) | |
|
[M83293] |
(SIV-stm) | |
|
sykes monkey SIV |
[L06042] |
(SIV-syk) |
* Represent cross-species transmission of SIV-sm in captivity.
Tentative Species in the Genus
None reported.
|
|  |
