Question

If the DNA has following sequence then what would be sequence in newly synthesized protein from this DNA?
3'-TAC CAT GCA TGC ATG CAT GCA TGC ATT GGC-5' Template Strand
5'-ATG GTA CGT ACG TAC GTA CGT ACG TAA CCG-3' Coding Strand

• A. Met – Val –Arg – Thr – Tyr – Val – Arg – Thr
• B. Val –Arg – Thr – Tyr – Val – Arg – Thr
• C. Met – Val –Arg – Thr – Tyr – Val – Arg – Thr – Asn
• D. Met - Val –Arg – Thr – Tyr – Val – Arg – Thr – Asn – Pro

Answer 1

The correct option is B Val –Arg – Thr – Tyr – Val – Arg – Thr

mRNA synthesized from this DNA would have sequence (Replace T with U on Coding strand):
5’ AUG GUA CGU ACG UAC GUA CGU ACG UAA CCG 3’
The start codon AUG which codes for methionine will be removed during processing of the polypeptide.
GUA - Valine
CGU - Arginine
ACG - Threonine
UAC - Tyrosine
UAA isa top codon so, the translation will stop at this point.
Hence, the protein will have the sequence
Val –Arg – Thr – Tyr – Val – Arg – Thr