Question

U C A G UUU · UCU 1 UAU U Phe 1 UGU Tyr! UGC Cys UUC I UCC I UAC C U 1 Ser UUA UCA Leu UUG UCG CUU CCU UAA Stop UGA Stop A UAG Stop UGG Trp G CAU CGU His CGC С Arg ТСАА CGA Gin! CAG CGG G CUC 1 ССС "cac Leu Pro CUA ICCA CUG CCG First mRNA base (5' end of codon) Third mRNA base (3' end of codon) AUU ACU AAU AGU U Asn Ser AUC АСС AAC AGC C A Thr! ТААА 1 AUA ACA AGA A 1 Lys Arg AUG Met or start ACG AAG AGG G GUU GCU GAU GGU Asp GUC GCC GAC GGC C 1 Val Ala Gly GUA GCA GAA GGA A 1 1 Glu - GUG GCG GAG GGG G

Follow the instructions below to answer questions about Replication, Transcription & Translation.

3’- T   A   C A   C   C   G   G   T   C   A   G   G   T   G A   T   C -5’

A. Imagine that the sequence shown represents one strand of a gene sequence. What would be the sequence of the complementary strand of DNA? Write out your answer, indicating correct polarity (5' and 3' ends) on your new strand. (1.5 points)

B. Now imagine that the new strand that you just created is the coding strand when it comes to Transcription. (The strand shown at the top can thus be thought of as the template strand). Knowing that this is the case, write out the correct mRNA sequence that this gene would produce, again indicating correct polarity. (2 points)

C. The mRNA you produced in "B" is now ready to be translated! Using the Codon Table at the top of the page, provide the entire polypeptide sequence that would be produced from your mRNA. Indicate the correct polarity of your protein sequence by indicating the N-terminus and C-terminus. (2.5 points)

D. What would be the correct anticodon sequence that would be used to recognize codon #4 in your mRNA sequence? Don't forget to once again indicate polarity! (1.5 points)

E. Mutations can drastically alter the sequence of the final polypeptide produced. Show how a mutation in your mRNA sequence from “B” could result in a nonsense mutation in the final polypeptide. For full credit, write out both the modified mRNA and the modified polypeptide sequences, indicating polarityon each as before. (4 points)

Answer 1

Given sequence 3'- TACA CC GGICAGGI GAT C-5' of the sequence strean op would be : complementary 5'- ATGT GGCCA GT CC, A CTA G- 8'. 1:11 MRNA that the sequence would gene produce :- 5'- A0 6.0 G G cc A. G U 4 G A c o A 6- 3'. Polypeptid sequence produced from the mRNA in "S". Methionine - Tryptophan - Propine valine - Aspartate Notenminal C terminal. Antieod on codon #4, for that is for GUG would be СА с. mutation, nonsense single a nucleotide base Ey. During change result in stop codon. PIA Eguese the #2 codon in "B" gets changed to 'UGA from 'OGG', The stopi at polypeptide would Methione MRNA-> Modified 5'- AUG UG A CCA GUG GAC UA G-3' New polypeptide Methionine.