What is the process of DNA transcription in relation to Human Immunodeficiency Virus (HIV)?

From the Guidelines

DNA Transcription in HIV

DNA transcription in regards to HIV refers to the process by which the viral RNA genome is transcribed into DNA, which is then integrated into the host cell's genome. This process is facilitated by the enzyme reverse transcriptase, which is inhibited by nucleoside reverse transcriptase inhibitors (NRTIs) such as tenofovir disoproxil fumarate and emtricitabine 1.

• The reverse transcription process is a critical step in the HIV life cycle, as it allows the virus to convert its RNA genome into DNA, which can then be integrated into the host cell's genome.
• NRTIs and non-nucleoside reverse transcriptase inhibitors (NNRTIs) are classes of antiretroviral drugs that target the reverse transcriptase enzyme, preventing the transcription of viral RNA into DNA 1.
• Other classes of antiretroviral drugs, such as protease inhibitors (PIs) and integrase inhibitors (IIs), also play important roles in suppressing HIV replication by targeting various stages of the viral life cycle.
• The use of antiretroviral therapy (ART), which typically involves a combination of multiple drugs from different classes, has been shown to effectively reduce the amount of virus in the body and prevent transmission 1.
• The choice of ART regimen can vary depending on individual patient factors, such as viral load and resistance patterns, as well as the availability and cost of different medications 1.

From the FDA Drug Label

Efavirenz is an NNRTI of HIV-1. Efavirenz activity is mediated predominantly by noncompetitive inhibition of HIV-1 reverse transcriptase. FTC, a synthetic nucleoside analog of cytidine, is phosphorylated by cellular enzymes to form emtricitabine 5'-triphosphate (FTC-TP), which inhibits the activity of the HIV-1 reverse transcriptase (RT) by competing with the natural substrate deoxycytidine 5'‑triphosphate and by being incorporated into nascent viral DNA resulting in chain termination

The process of DNA transcription in relation to Human Immunodeficiency Virus (HIV) is not directly described in the provided drug labels. However, it can be inferred that the reverse transcription process is crucial, where the HIV-1 reverse transcriptase enzyme converts the viral RNA into DNA.

• Reverse transcription is the process by which HIV-1 converts its RNA genome into DNA, which can then be integrated into the host cell's genome.
• Efavirenz and emtricitabine are antiretroviral drugs that inhibit the HIV-1 reverse transcriptase enzyme, preventing the conversion of viral RNA into DNA.
• The exact process of DNA transcription in relation to HIV is not explicitly described in the provided text, but it is related to the inhibition of reverse transcriptase by these drugs [2] [3].

From the Research

DNA Transcription in HIV

The process of DNA transcription in relation to Human Immunodeficiency Virus (HIV) involves the conversion of the viral RNA genome into a double-stranded DNA copy, which is then integrated into the host cell chromosome. This process is essential for the replication of the virus.

Reverse Transcription

• Reverse transcription is a discontinuous process carried out by the viral encoded reverse transcriptase, which displays DNA polymerase activities on RNA and DNA templates as well as an RNase H activity that degrades transcribed RNA 4.
• The initiation of reverse transcription is a complex reaction that requires the binding of a cellular tRNA primer to a complementary sequence in the viral genome, called the primer binding site (PBS) 5.
• The viral enzyme reverse transcriptase (RT) recognizes this RNA-RNA complex and catalyzes the extension of the 3' end of the tRNA primer, with the viral RNA (vRNA) acting as template 5.

Role of Reverse Transcriptase and Integrase

• Reverse transcriptase (RT) and integrase (IN) are two indispensable enzymes in HIV-1 replication, with RT responsible for the transformation of the single-stranded RNA viral genome into double-stranded DNA, and IN catalyzing the integration of viral DNA into the host DNA 6.
• The interaction between RT and IN is required for reverse transcription during HIV-1 replication, with the C-terminal domain (CTD) of IN necessary and sufficient for this binding 7.

Mechanism of Reverse Transcription

• The mechanism of reverse transcription involves the transition of the single-stranded viral RNA into double-stranded proviral DNA, which is then integrated into the host chromosome 8.
• The process of reverse transcription is highly specific, with most retroviruses restricted to the use of the cognate, self-tRNA primer 5.
• The viral enzyme reverse transcriptase plays a pivotal role in the life cycle of the virus and is consequently an interesting target for anti-HIV drug therapy 8.