In October 2023, the Indian Institute of Science Education and Research Bhopal identified ciTRAN. Which of the following statements is/are CORRECT about this achievement?
1. IISER Bhopal identified a specific circular RNA (circRNA) called 'ciTRAN'
2. It plays a crucial role in the multiplication of the AIDS-causing HIV-1 virus within the human body.
3. This research was led by Dr. Ajit Chande from the Department of Biological Sciences, IISER Bhopal.
4. ciTRAN helps the process of copying genetic information from the virus.
​

Correct option is D

​The correct answer is (d) 1, 2, 3 and 4

Explanation:

• Indian Institute of Science Education and Research (IISER) BhopalciTRANIn October 2023, researchers from the identified a specific circular RNA (circRNA) named , which plays a crucial role in the replication of the HIV-1 virus.
• Dr. Ajit ChandeVprSRSF1This discovery was led by from the Department of Biological Sciences at IISER Bhopal. The study revealed that ciTRAN is induced by the HIV-1 viral protein and interacts with the host protein , a known repressor of HIV-1 transcription.
• By sequestering SRSF1, ciTRAN promotes efficient viral transcription, thereby aiding in the replication of the virus.
• This research opens up new avenues for developing therapeutic interventions targeting circRNAs to combat HIV-1 infection.​

Information Booster:

ciTRAN and HIV-1 Replication:

• Identification:circDR-Seq Using a novel protocol called , researchers captured circRNAs from HIV-1-infected T cells and identified ciTRAN as a key player in viral replication.
• Mechanism:Vpr-dependent manner HIV-1 infection induces ciTRAN expression in a , leading to the sequestration of SRSF1. This interaction prevents SRSF1 from repressing HIV-1 transcription, thereby enhancing viral gene expression.
• Therapeutic Implications: The study also demonstrated that an SRSF1-inspired mimic could inhibit viral transcription, regardless of ciTRAN induction, suggesting potential therapeutic strategies targeting the ciTRAN-SRSF1 interaction. ​

Significance of Circular RNAs:

• Role in Gene Regulation: Circular RNAs, like ciTRAN, are known to play pivotal roles in regulating gene expression and are essential for various biological processes.
• Challenges in Detection: Characterizing circular RNAs can be challenging due to their less abundant nature and closed-loop structure, which makes them difficult to detect in their native form. ​

Additional Knowledge:

Circular RNA (circRNA):

• Structure: CircRNAs are a class of RNA molecules characterized by their covalently closed loop structure, lacking 3' and 5' ends.
• Functions: They are involved in various cellular processes, including regulation of gene expression, splicing, and protein translation.
• Research Significance: The identification of ciTRAN highlights the importance of circRNAs in viral infections and their potential as therapeutic targets.​

HIV-1 and Viral Transcription:

• Viral Protein Vpr: Vpr is a multifunctional protein encoded by HIV-1 that influences various stages of the viral life cycle, including transcription and immune evasion.
• Host Protein SRSF1: SRSF1 is a splicing factor that can repress HIV-1 transcription. The interaction between ciTRAN and SRSF1 represents a novel mechanism by which HIV-1 enhances its replication.