Prelims (GS I) - General Science| Current events of national and international importance.
Mains (GS III) – Science and Technology- developments and their applications and effects in everyday life.
Why in news?
Researchers recently reported developing an RNA-based antiviral agent that confers strong protection against cucumber mosaic virus (CMV).
- Plant virus – It is a microscopic, infectious agent that causes diseases in plants.
- It destroys a significant portion of annual crops worldwide.
- Unlike bacteria or fungi, viruses cannot be controlled with pesticides or fungicides.
- Cucumber Mosaic Virus (CMV)
- CMV is a plant virus that infects more than 1,200 plant species, including critical food crops like cucumbers, squash, and cereals, and medicinal plants.
- Spread through - sap-sucking insects called aphids.
- Effects - Infected plants develop mosaic discoloration, stunted growth, and commercially unviable fruits.
- Severity - Nearly 90 aphid species are capable of transmitting CMV, making outbreaks difficult to contain.
In India, CMV causes 25-30% yield losses in banana plantations.
|
Current RNA-based Crop Protection Techniques
|
- RNA Silencing – It is a natural defense mechanism in plants.
- When a virus infects a plant, it introduces double-stranded RNA (dsRNA).
- The plant responds by activating Dicer-like enzymes (DCLs), which slice the dsRNA into small fragments called small interfering RNAs (siRNAs).
- These siRNAs guide the plant's defense system to recognize and destroy viral RNA.
- Limitations – Not all siRNAs are effective, and some plant viruses can mutate rapidly.
- Host-induced gene silencing (HIGS) – It works by genetically modifying plants to produce virus-fighting dsRNA in their cells.
- Limitations - High production costs.
- Spray-induced gene silencing (SIGS) - More flexible alternative to HIGS where plants are treated with RNA sprays instead of being genetically modified.
- Limitations - Traditional dsRNA Spray formulations produce a random mix of siRNAs, and many are ineffective.
|
Key Findings of the Research
- Researchers first screened and identified the most potent siRNAs against CMV.
- These specially selected siRNA bind to the virus’s genetic material to trigger a stronger antiviral response.
- Then they designed effective dsRNA (e-siRNAs) enriched with highly functional siRNA.
- These e-siRNAs were assembled into dsRNA constructs for more targeted protection.
- CMV infected plants treated with the enhanced siRNA had almost 80% lower viral load.
- The new dsRNA formulation outperformed traditional dsRNA and it is effective against multiple CMV strains.
Advantages of the New Approach
- More precise targeting of viral particles of the most vulnerable genetic regions.
- Stronger defense by targeting multiple regions of viral genome simultaneously.
- The effective dsRNA can be redesigned in about a month to target new viral strains.
Reference
The Hindu| RNA-based antiviral
