5GGCTATATATTACCGATGAGGCGTTCGAATGACTAGCTACACATTATAACGAATTTT3

5’GGCTATATATTACCGATGAGGCGTTCGAATGACTAGCTACACATTATAACGAATTTT3’ 3’CCGATATATAATGGCTACTCCGCAAGCTTACTGATCGATGTGTAATATTGCTTAAAA5’

• The promoter for the gene is: 5’ TATATATT -3’

• The terminator for the gene is: 5’ ATTAT-3’

• The following intron is removed during RNA processing 5’UUCGAA 3’

• Assume transcription proceeds from left to right

a. Above the DNA shown, indicate where RNA polymerase would bind to initiate transcription.

b. Show the structure of the mature mRNA that will be formed from this DNA. Be sure to indicate the 5’ and 3’ ends. c. Show the sequence of amino acids coded for by this gene.

d. Under each amino acid, show the anticodons that would be present on each tRNA that would be needed to deliver the amino acids to the ribosome for protein synthesis.

Solution

Answer: Keeping in view the above strand and Template Strand and the lower one as Coding strand, the question are answered as:

a) RNA Polynerase will initiate transcription at the 18th base, because from the mid of promoter (5’ TATATATT -3’) to the initiation base there should be 10 bases. Therefore, first base will be G

5’GGCTATA TATTACCGAT GAGGCGTTCGAATGACTAGCTACACAT TATAACGAATTTT3’

b) the structure of mRNA wil be after setting termination region from the mid of 5’ ATTAT-3

3\' CUCCGCAAGCUUACUGAUCGAUGUGUA 5\'

c) Before mRNA under goes translation, introns are removed from the mRNA chain. Therefore, after removing the intron (5’UUCGAA 3’) the new sequence of mRNA willbe:

    3 CUCCGCACUGAUCGAUGUGUA 5

This mRNA chain will have following triplet codons

    3 CUC CGC ACU GAU CGA UGU GUA 5 or 5\' AUG UGU AGC UAG UCA CGC CUC

Following amino acids will be synthesized from this mRNA chain keeping initiation codon (AUG) and Stop codon (UAG) under consideration

Met, Cys, Ser

d) Following anticodons that would be present on each tRNA that would be needed to deliver the amino acids to the ribosome for protein synthesis.

5’AUG UGU AGC UAG 3’

Anticodon sequence for AUG is UAG (3\' UAG 5\' on tRNA)

Anticodon sequence for UGU is ACA (3\' ACA 5\' on tRNA)

Anticodon sequence for AGC is UCG   (3\' UCG 5\' on tRNA)

Anticodon sequence for UAG is AUC Stop Codon