Human immunodeficiency virus type 1 trans-activator of transcription messenger RNA (HIV-1 tat mRNA)

HIV-1 tat mRNA is the messenger RNA transcript responsible for the synthesis of the Trans-activator of transcription (Tat) protein, which is essential for the replication of Human immunodeficiency virus type 1 (HIV-1). The Tat protein acts as a potent activator of viral gene expression by binding to the trans-activation response (TAR) element located at the 5' end of nascent viral RNA transcripts (Karn & Stoltzfus, 2012, Cold Spring Harb Perspect Med). This binding event recruits the human positive transcription elongation factor b (p-TEFb) complex, which phosphorylates the C-terminal domain of RNA polymerase II, significantly increasing the efficiency of transcriptional elongation. Because the virus cannot replicate effectively without Tat, the tat mRNA serves as a high-value target for nucleic acid-based therapeutics such as antisense oligonucleotides, siRNAs, and ribozymes (Castanotto et al., 2002, Blood). By destroying or blocking the translation of this mRNA, these therapies aim to inhibit viral production and potentially maintain the virus in a state of deep latency. Despite therapeutic promise, challenges such as the high mutation rate of HIV-1 and the need for efficient delivery systems to reach infected cells remain primary obstacles in clinical development (Polydotou et al., 2023, Pharmaceutics).

Other names

HIV-1 tat transcriptTat-encoding mRNAHIV-1 trans-activator of transcription mRNA

Antisense inhibition, RNA interference (RNAi), or ribozyme-mediated cleavage leading to mRNA degradation or translation blocking, which prevents the synthesis of the Tat protein and halts viral transcription.