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 immu ...

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 A hairpin or hair pin is a long device used to hold a person's hair in place. It may be used simply to secure long hair out of the way for convenience or as part of an elaborate hairstyle or coiffure. The earliest evidence for dressing the hai ...

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 or ...

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 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 gene ...

IER3 Radiation-inducible immediate-early gene IEX-1 is a protein that in humans is encoded by the ''IER3'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meani ...

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 produc ...

, and

Bim ''Bim'' is a 1974 Trinidad and Tobago film written by Raoul Pantin and directed by Hugh A. Robertson. It was described by Bruce Paddington as "one of the most important films to be produced in Trinidad and Tobago and... one of the classics of Ca ...

. 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 (formerly known as papovavirus). It was identified by electron microscopy in 1965 by ZuRhein and Chou, and by Silverman and ...

) 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 {{molecular-cell-biology-stub