The following is the TEMPLATE STRAND of the DNA encoding a short peptide: 5\'-TT

Question

The following is the TEMPLATE STRAND of the DNA encoding a short peptide: 5'-TTAGAGGGGTAACGCGGCGCGGTTTTCTGCGCCGGTCACGCCTGCTCGTGACAGCAACAT-3'a. Assuming that there are no introns contained in this sequence, what will the corresponding mRNA sequence, written 5'-- > 3'? b. Using the attached codon chart, what will be the amino acid sequence for the peptide? Use the three letter amino acid designations. Label the N and C-terminus of the sequence. c. A mutant contains a slightly altered sequence for this peptide. Instead of the underlined GT, it contains AC (an A at position 35, replacing the G, and a C at position 36, replacing the T). This mutation will convert a(n) __________ (original amino acid) to a(n) _____. (new amino acid) This is would be what type of mutation? (Circle one) Nonsense Missense Silent Neutral Frameshift d. Briefly discuss the possible effects of this substitution on the peptide.

Explanation / Answer

a) The template strand is

5' TTA GAG GGG TAA CGC GGC GCG GTT TTC TGC GCC GGT CAC GCC TGC TCG TGA CAG CAA CAT 3'

Corresponding mRNA is

3' AAU CUC CCC AUU GCG CCG CGC CAA AAG ACG CGG CCA GUG CGG ACG AGC ACU GUC GUU GUA 5'

corresponding mRNA FROM 5' to 3' end is,

5' AUGUUGCUGUCACGAGCAGGCGUGACCGGCGCAGAAAACCGCGCCGCGUUACCCCUCUAA 3'

b) The aminoacid sequence is,

N terminus Asn-Leu-Pro-Ile-Ala-Pro-Arg-Gln-Lys-Thr-Arg-Pro-Val-Arg-Thr-Ser-Thr-Val-Val-Val C terminus

c) GT is replaced by AC.

so insted of proline, leucine is formed.

This is an example of missense mutation.

d) The subsitution on the peptide causes missense mutation. As a result of missense mutation, different aminoacid is produced instead of the original aminoacid. As a result, the functions of protein are altered.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.