The Question is from neet-botany biomolecules-biology , and it was created by the author B VENKAT

Question

A mutation in a tRNA molecule alters its anticodon sequence from 3'-AUC-5' to 3'-AUA-5'.  Assuming the wobble hypothesis applies, which of the following changes in protein synthesis is MOST likely to occur?

B VENKAT · Accepted Answer

## CORE INFORMATION
✓ **Answer**: C
## CONCEPT FRAMEWORK
 **Primary Concept**: Wobble Hypothesis and tRNA function in translation
 **Related Topics**:  Genetic code, codon-anticodon pairing, mutations
 **Prerequisites**: Understanding of the central dogma of molecular biology, the genetic code, and the role of tRNA in translation.
## SOLUTION PATHWAY
**Given Information**:
  The anticodon of a tRNA changes from 3'-AUC-5' to 3'-AUA-5'.
  The wobble hypothesis applies.
**Method & Steps**:
 1. Understand the wobble hypothesis: The wobble hypothesis states that the first base (5' end) of the anticodon can pair with more than one base at the third position (3' end) of the codon. This allows a single tRNA to recognize multiple codons.
  Reasoning: This flexibility in base pairing at the wobble position explains how a limited number of tRNAs can decode all 61 codons that specify amino acids.
  Formula/Rule: None directly applicable; this is a conceptual understanding.
 2. Analyze the anticodon change: The original anticodon 3'-AUC-5' is complementary to the codon 5'-UAG-3'.  The mutated anticodon 3'-AUA-5' is complementary to the codon 5'-UAU-3'.
  Working:  Let's consider the amino acids specified by these codons.  UAG is a stop codon. UAU codes for Tyrosine.
  Key Point: The wobble position is the first base of the anticodon (5' end).  The change is in this position.
 3. Determine the effect of the mutation: While the codons are different, they might still code for the same amino acid due to the degeneracy of the genetic code. The wobble position allows for some flexibility in base pairing, potentially resulting in the same amino acid being incorporated even with a different codon.
  Result: The most likely outcome is that the mutant tRNA will recognize a different codon, but still incorporate the same amino acid. This is because the wobble base (the first base of the anticodon) is involved, and this base pairing is often less stringent.
  Verification:  Consider other possibilities.  Premature termination is unlikely because UAU is not a stop codon.  Incorporating a different amino acid is possible, but less probable given the wobble hypothesis.
 ## OPTION ANALYSIS
A :x: Premature termination requires a stop codon, but UAU codes for tyrosine.
B :x:  A different amino acid is possible, but less likely than the same amino acid being incorporated due to the wobble effect.
C ✓: The wobble hypothesis allows for some flexibility in base pairing, making it possible for the mutated tRNA to recognize a different codon coding for the same amino acid.
D :x: The mutation clearly changes the anticodon and, thus, the codon recognized. This will have an effect.
 ## LEARNING AIDS
 **Common Mistakes**:
  1.Ignoring the wobble hypothesis:  Failing to consider the flexibility of base pairing at the wobble position.
  How to avoid:  Carefully review the rules of the wobble hypothesis and how it affects codon-anticodon interactions.
  2.Assuming a strict Watson-Crick base pairing: Forgetting that the wobble position allows for non-standard base pairing.
  How to avoid:  Remember that the wobble hypothesis introduces exceptions to the standard base pairing rules.
 **Quick Tips**:
  1.Focus on the first base of the anticodon when analyzing wobble effects.
  2.Remember the degeneracy of the genetic code and how it relates to the wobble hypothesis.

B VENKAT · Answer

Protein synthesis will be terminated prematurely.

B VENKAT · Answer

A different amino acid will be incorporated at the corresponding codon.

B VENKAT · Answer

The correct Option is "The mutant tRNA might recognize a different codon but still incorporate the same amino acid."

B VENKAT · Answer

The mutation will have no effect on protein synthesis.

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