Question

1. (5 pts) A tRNA with the anticodon 3’- GAA - 5’ would bind to which of the following codons?

1. 5’ – CUU – 3’
2. 5’ – CUC – 3’
3. 5’ – CUA – 3’
4. 5’ – CUG – 3’
5. Any of the above!

Answer 1

The answer is - E. Any of the above

3' GAA 5' normally binds to 5' CUU 3' through Watson Crick base pairing.

But according to wooble hypothesis proposed by Crick the nucleotide at 5' end of tRNA anticodon is capable of pairing with more than one nucleotide at the 3' end of thr mRNA codon.

That is the bonding between the anticodon of tRNA and the codon of mRNA is very strict forvthe first two positions but is flexible at the third position.

So codons that specify same amino acid differs only at third position.

So 3' GAA 5' can bind with all CUU, CUC, CUA and CUG and all codes for same amino acid that is leucine.