Question

Which of the following statements are correct regarding the process of RNA interference?
i. This is used to prevent the infestation of protozoans
ii. It takes place in some eukaryotic and all prokaryotic organisms as a method of cellular defense.
iii. The method involves silencing of a specific mRNA due to complementary dsRNA molecules.
iv. It is a novel strategy to produce pest-resistant plants.

A. (iii) and (iv)
B. (i) and (iii)
C. (i) and (ii)
D. (ii), (iii) and (iv)

Answer 1

Hint: RNA interference is one of the highly conserved, post-transcriptional process in the cell of eukaryotic organisms which is mediated by dsRNA (double stranded RNA) molecule in order to regulate the expression of protein coding genes. Historically, RNAi was also known as quelling, post-transcriptional gene silencing (PTGS), and co-suppression.

Complete answer:
RNAI or RNA interference is a regulatory mechanism that occurs in all eukaryotic organisms as a method of cellular defense. During the process, the targeted mRNA molecules get silenced or neutralized and so RNA molecules inhibit translation or expression of genes.
 Using Agrobacterium vectors, the targeted nematode specific genes are introduced in the host plant of DNA and it produces both sense and antisense RNA in the host cells. These two RNAs are complementary to each other which then forms a dsRNA (double-stranded RNA) molecule that initiates the process of RNA Interference.
 The important arm of RNA interference includes the microRNAs (miRNAs). RNA interference (RNAi) is a biological process of all eukaryotic cellular organisms that utilizes small double-stranded RNA (dsRNA) molecules as triggers in order to direct the homology-dependent control of gene activity.
RNA interference involves silencing of a specific mRNA due to complementary dsRNA molecules. It is a novel strategy in order to produce pest-resistant plants.

Hence, the correct answer is option (A).

Note: During RNA interference, long double stranded RNA is cut down or "diced" into smaller fragments with the use of an enzyme called "Dicer". These small fragments are considered as small interfering RNAs (siRNA) which bind to proteins from a special family known as the Argonaute proteins.