In plant genetic engineering, what does “antisense technology” aim to accomplish at the gene-expression level?

Introduction / Context:
Antisense technology is a gene-silencing approach used in plants and other organisms to downregulate specific genes. By designing nucleic acid sequences that are complementary to the target mRNA, researchers can prevent translation and reduce the corresponding protein.

Given Data / Assumptions:

• Antisense RNA is complementary to the target mRNA.
• Binding forms RNA–RNA duplexes that hinder translation or promote degradation.
• Goal is specific knockdown, not wholesale genomic changes.

Concept / Approach:
When antisense RNA is expressed in a cell, it base-pairs with the target mRNA. This pairing can block ribosome access or recruit RNase H–like activities that degrade the mRNA. The result is selective gene silencing, allowing researchers to modify traits such as fruit softening, pigment formation, or metabolic flux.

Step-by-Step Solution:

Verification / Alternative check:
Classic examples include antisense suppression of polygalacturonase in tomato to delay softening and antisense chalcone synthase to modulate flower color.

Why Other Options Are Wrong:

• B: Combining genetic material describes hybridization or recombinant DNA, not antisense.
• C/D: Cell fusion or transfer changes cells, not specific gene expression.
• E: Antisense does not globally upregulate pathways; it downregulates specific targets.

Common Pitfalls:
Confusing antisense with RNA interference; mechanisms overlap in outcome (silencing) but differ in molecular details.

Final Answer:
Selectively block expression of a target gene