About circular RNA:
- Ribonucleic acid is a molecule in living cells that carries genetic information and helps in the production of proteins.
- RNAs are in general straight-chain, free-end structures but these circular RNA (‘circRNA’ ) forms a closed-loop.
- The circRNA plays a pivotal role in regulating gene expression and is essential for various biological processes.
- Its role in HIV-1 replication has remained unclear for a long time.
- Characterizing circular RNA can be tricky because it usually is less abundant, making it further challenging to detect in the native form.
- During viral infections, there's so much information from the virus that it can make it hard to find the less common ones like circular RNA.
Highlights about the recent findings
- The researchers developed a novel approach called ‘circDR-Seq’, to successfully capture circRNAs from T-cells (white blood cells) infected with the HIV-1 virus and identified a specific circRNA named ciTRAN, which plays an important role in the multiplication of the virus.
- HIV-1 viral protein R (VpR) is a multifunctional protein that plays specific roles at multiple stages of the HIV-1 viral life cycle and affects anti-HIV functions of the immune cells.
- Further found that HIV-1 infection induces ciTRAN expression in a Vpr-dependent manner and that ciTRAN interacts with serine/arginine-rich splicing factor 1 (SRSF1), a protein known to repress HIV-1 transcription,”
- How does this work?
- The results suggest that HIV-1 hijacks ciTRAN which is generally altered during immunological signaling, inflammation, and viral infection.
- It further prevents (SRSF1) from doing its job, thereby promoting efficient viral transcription.
- In addition, researchers demonstrated that an SRSF1-inspired mimic can inhibit viral transcription regardless of ciTRAN induction.
- The hijacking of a host circRNA thus represents a previously unknown facet of primate lentiviruses in overcoming transmission bottlenecks,
