Before You Begin
Question #47684
The Question
In an attempt to use RNA interference (RNAi) for the therapeutic silencing of a mutant disease-causing allele, a researcher introduces a high dose of long exogenous double-stranded RNA (dsRNA) into a human cell line. While the target gene is successfully silenced, the cells exhibit a severe inflammatory response and a widespread failure of normal endogenous gene regulation, leading to apoptosis. Which of the following is the most scientifically accurate explanation for this dual systemic fallout?
Options
- A.
The exogenous dsRNA acts as a mobile genetic element (transposon), integrating into the host genome and causing widespread insertional mutagenesis.
- B.
The long dsRNA is recognized as a viral signature, triggering an interferon response, while the excess siRNA saturates the RISC complex, disrupting endogenous miRNA-mediated regulation.
- C.
The dsRNA directly binds to the promoter regions of non-target metabolic genes in the nucleus, inducing widespread Transcriptional Gene Silencing (TGS).
- D.
The exogenous dsRNA competitively inhibits RNA-dependent RNA polymerase (RdRP), preventing the amplification of endogenous regulatory RNAs required for cell survival.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Monascus_purpureus|HMG-CoA reductase|Cholesterol biosynthesis
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often view RNAi purely as a targeted 'magic bullet' (as seen in the NCERT nematode example) and fail to synthesize it with concepts from Human Health and Disease.
The trap lies in forgetting that the molecular machinery (RISC) is shared with the cell's own miRNA system, and that mammalian cells possess innate immune defenses (interferons) against exogenous dsRNA, which mimics viral genomes.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Microbes in Human Welfare - Class 12 |
| Concept | Bioactive Molecule Origin |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |