Human immunodeficiency virus type 1 long terminal repeat (HIV-1 LTR)

The Human immunodeficiency virus type 1 long terminal repeat (HIV-1 LTR) is a critical DNA sequence that flanks the viral genome and serves as the primary promoter and enhancer for viral gene expression. It contains essential binding sites for both viral proteins, such as Tat, and host cellular transcription factors like NF-kappaB and SP1, which orchestrate the transition between viral latency and active replication (Source: PubMed, PMC4135430). The LTR is divided into three regions: U3, R, and U5, with the 5' LTR acting as the promoter for the entire viral transcript and the 3' LTR providing the polyadenylation signal (Source: Nature Reviews Microbiology, 2012). As a therapeutic target, the HIV-1 LTR is central to 'block and lock' strategies aimed at permanent epigenetic silencing of the provirus and 'shock and kill' strategies intended to reactivate latent reservoirs for immune clearance (Source: NIH, NIAID). Furthermore, modern gene-editing tools like CRISPR/Cas9 are being developed to target and excise the LTR sequence directly from the host genome to achieve a functional cure (Source: Molecular Therapy, 2017). Because the LTR is unique to the virus, it offers a high degree of specificity, although the high mutation rate of HIV-1 presents a significant challenge for long-term efficacy (Source: Journal of Virology, 2019).

Other names

HIV-1 LTR5' LTR3' LTRHIV-1 promoterLong terminal repeat

Inhibition of viral transcription through epigenetic silencing, competitive binding to promoter elements, or direct excision/disruption of the LTR sequence via gene editing technologies.