Question

The extent of complementarity of a miRNA with its target mRNA determines ______________________.

(a) whether the mRNA will be immediately degraded or whether the mRNA will first be transported elsewhere in the cell before degradation
(b) whether the mRNA will be transported to the nucleus
(c) whether RISC is degraded
(d) whether the miRNA synthesizes a complementary strand

Answer 1

The degree of complementarity between miRNA and mRNA influences whether the mRNA is immediately degraded or transported for later degradation or translational repression. The correct option is (b) whether the mRNA will be transported to the nucleus

Step-by-step explanation:

The extent of complementarity of a miRNA with its target mRNA determines whether the mRNA will be immediately degraded or whether the mRNA will first be transported elsewhere in the cell before degradation.

During post-transcriptional regulation, miRNAs associate with the RNA-induced silencing complex (RISC) to target and control the fate of mRNAs. If a miRNA is fully complementary to its target mRNA, it typically leads to direct cleavage and degradation of the mRNA by the RISC complex.

However, if the complementarity is partial, it may instead lead to translational repression, wherein the mRNA is not immediately degraded but may be transported within the cell and broken down later or its translation into protein is inhibited.

This specificity in the miRNA-mRNA interaction is crucial for regulating gene expression and ensuring precise control over protein synthesis. The correct option is (b) whether the mRNA will be transported to the nucleus