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Going Through the Motions: Transcription and Translation in Action
Due Date: _________________________________
You will need:
a) A dark colored bristol board (only front is to be used)
b) Clear tape
c) Highlighters (at least 3 colours)
TERMINOLOGY: Define the following terms
a) Upstream
b) Downstream
TRANSCRIPTION:
Where to Start? Initiation
1. Cut out and build your double stranded DNA by attaching the bottom of segment 1 to the
top of segment 2 and so on.
2. Look at your double stranded DNA and label the orientation of your two strands.
a. Now to find where your gene starts. Based on what you learned in class, what
nucleotide sequence(s) are you looking for? HIGHLIGHT these in YELLOW on
your DNA template strand.
Research
3. There are at other sequences, in addition to the initiation sequence, that are located in the
promoter region.
a. List two sequences you would find in the DNA in prokaryotes, and identify where
they are located specifically.
4. Determine the template strand. Label this as your template strand by putting RED
STARS at the 3’ and 5’ ends.
5. Cut down the middle of the double stranded DNA to model the unzipping of DNA by the
enzyme called: _____________________________________.
6. Set aside the non-template strand; Some of you may want to keep it just in case, if you
make a mistake….. Do not lose your strands! You will need to put it back on the board
AS YOU FOUND IT ORIGINALLY
Elongation
8. Build your primary mRNA by using the RNA nucleotides. Then label the orientation of
your mRNA.
 Hint: start transcription right after the 1st initiation sequence.
 Hint: after you find your stop sequence, continue transcribing for another 20
nucleotides.
 What is this section called?
Termination
9. There are 3 possible nucleotide sequences on the mRNA which help with termination.
List these sequences and then indicate what these sequences look like on the DNA
template strand. INCLUDE ORIENTATION! HIGHLIGHT your termination sequence
in PINK.
POST-TRANSCRIPTIONAL MODIFICATION (eukaryotes only)
Research
1) There are three types of post-transcription modifications that occur in eurkaryotes.
Describe the purpose of each of the post-transciptional modifications. Identify and label
these modification pieces on your Bristol board and keep them for handing in.
a. Cleaving and Splicing introns
b. 3’ processing
c. 5’ processing
Now modify you mRNA appropriately based on the next steps:
Research
2) SPLICING and CLEAVING
a. What is another name for the 5’ splice junction?
b. What does this sequence for the 5’splice junction always start with?
c. What is the purpose of the 5’splice junction?
d. What is another name for the 3’ splice junction?
e. What does this sequence always have and end with?
f. What is the purpose of the 3’ splice junction?
g. Find our intron(s) by identifying the 5’splice junction and the 3’splice junction
and attaching the subunits in this order:
i. First attach U1
ii. Then attach U2AF
iii. Then attach U2 (which should attach to the U2AF)
iv. Your intron is found in between the subunits.
h. To splice, you will need to complete the formation of the spliceosome by
attaching U1 and U2 together.
i. Now tape U1 and U2 so that they fit with this unit.
ii. Now you can cut / detach the intron from the rest of the mRNA.
3) Attach the 5’cap and 3’ poly A tail.
4) Looking at your MATURE mRNA, going from 5’ to 3’, list all the different components
that you encounter in your mRNA in order. Put this information in a chart. (hint: you
have at least 7 components – you may include components that have been removed)
TRANSLATION
Where to Start? Initiation
1) Create your own tRNA’s by attaching them to their appropriate amino acids (make
circles with 3 letter abbreciations). Use the genetic code to help you. Glue these on your
board free-floating“in the cytoplasm”. Then WRITE IN the anticodon along the base of
the tRNA.
2) What is the Shine-Dalgarno (prokaryotes) sequence of a mRNA? What is it used for?
Research
3) What is the Kozak sequence of an mRNA? What is it used for? HIGHLIGHT YOURS IN
BLUE.
Elongation
4. Draw your final peptide chain. You may use the a.a. provided in your textbook as a
guideline.
Termination - You are done!
What to hand in:
 BOOKLET of marks and answers

The list of components needs to be all “secured” / glued NEATLY and LABELED on
your DARK BRISTOL BOARD in their locations (nucleus or cytoplasm)