The
HIV
The human immunodeficiency viruses (HIV) are two species of '' Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the im ...
trans-activation response (TAR) element is an
RNA element which is known to be required for the trans-activation of the viral
promoter and for virus replication. The TAR
hairpin is a dynamic structure that acts as a binding site for the
Tat protein, and this interaction stimulates the activity of the
long terminal repeat
A long terminal repeat (LTR) is a pair of identical sequences of DNA, several hundred base pairs long, which occur in eukaryotic genomes on either end of a series of genes or pseudogenes that form a retrotransposon or an endogenous retrovirus o ...
promoter.
Further analysis has shown that TAR is a
pre-microRNA that produces mature microRNAs from both strands of the TAR stem-loop.
These miRNAs are thought to prevent infected cells from undergoing
apoptosis
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
by
downregulating the genes
ERCC1
DNA excision repair protein ERCC-1 is a protein that in humans is encoded by the ''ERCC1'' gene. Together with ERCC4, ERCC1 forms the ERCC1-XPF enzyme complex that participates in DNA repair and DNA recombination.
Many aspects of these two gen ...
,
IER3
Radiation-inducible immediate-early gene IEX-1 is a protein that in humans is encoded by the ''IER3'' gene.
This gene functions in the protection of cells from Fas- or tumor necrosis factor type alpha-induced apoptosis
Apoptosis (from ) is ...
,
CDK9
Cyclin-dependent kinase 9 or CDK9 is a cyclin-dependent kinase associated with P-TEFb.
Function
The protein encoded by this gene is a member of the cyclin-dependent kinase (CDK) family. CDK family members are highly similar to the gene produ ...
, and
Bim
Building information modeling (BIM) is an approach involving the generation and management of digital representations of the physical and functional characteristics of buildings or other physical assets and facilities. BIM is supported by vario ...
.
Human polyomavirus 2 (
JC virus
Human polyomavirus 2, commonly referred to as the JC virus or John Cunningham virus, is a type of human polyomavirus. It was identified by electron microscopy in 1965 by ZuRhein and Chou, and by Silverman and Rubinstein. It was later isolated in ...
) contains a TAR-homologous sequence in its late promoter that is responsive to HIV-1 derived Tat.
References
External links
*
miRBase page for hiv1-mir-TAR
MicroRNA
Cis-regulatory RNA elements
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