What would be the tRNA anticodon for the DNA sequence TAG? What amino acid would this tRNA carry?

Question

I am doing a project for biology and need to know this answer What would be the tRNA anticodon for the DNA sequence TAG? What amino acid would this tRNA carry?

Answer 1

Assuming your TAG is oriented 5' --> 3' which is usually the convention then:

DNA: 5' TAG 3'

the messenger RNA (mRNA) complements this

mRNA: 3' AUC 5'

mRNA is read from 5' to 3' so that means in the ribosome this codon will be read as

5' CUA 3'

The anticodon is the complement of this: 3' UAG 5'

CUA codes for the amino acid leucine, which the UAG tRNA would carry.

However if TAG is presented in the 3' --> 5' orientation

then the following are true:

DNA: 3' TAG 5'

RNA  5' AUC 3'

tRNA anticodon 3' UAG 5'

In this case the mRNA codon AUC codes for Isoleucine.

Answer 2

DNA  -- TAG

mRNA -UAG

tRNA   - AUC

mRNA is copied from the template strand, and so it has the same sequence as the coding strand of DNA, except that uracil is substituted for thymine. mRNA codon UAG codes for amber (stop). The tRNA with the anti-codon AUC does not carry any amino acid.