02.13 - Transcription Flashcards
It is the process of synthesising RNA from a DNA template.
Transcription
Which strand runs from the 3’–>5’ direction?
Template strand
The synthesised RNA appears similar to what strand?
Coding strand
Which of the following does not belong to the group?
a. Template strand
b. Anti-sense strand
c. Sense strand
d. Non-coding strand
c. Sense strand
Promoter sequences are found in which region?
a. Upstream the coding strand
b. Upstream the template strand
c. Downstream the coding strand
d. None of the above
a. Upstream the coding strand
What enzyme is responsible for transcription?
RNA polymerase
Which subunit of RNA polymerase facilitates the assembly of subunits?
Alpha 1
Which subunit of RNA polymerase serves as the promoter-binding site?
Alpha 2
Which subunit of RNA polymerase has 5
–>3’ polymerase activity?
Beta
Which subunit of RNA polymerase serves as the template-binding site?
Beta prime
What are the two functions of the catalytic site of RNA polymerase?
Helicase activity
Addition of NTPs (polymerase activity)
Which RNA polymerase subunit is in charge of stabilising the RNA molecule?
Omega
What non-protein component increases the affinity of RNA polymerase for the promoter region?
Sigma factor
This termination factor signals the end of transcription of termination factor-dependent termination.
Rho factor
What are the three phases of prokaryotic and eukaryotic transcription?
Initiation
Elongation
Termination
What are the two sequences that are found in the promoter region of prokaryotes?
-35 sequence (5'-TTGACA-3') Pribnow box (5'-TATAAT-3')
Where is the Pribnow box located?
a. 35 bases to the left of the start of transcription
b. 35 bases upstream of the coding strand
c. 8 to 10 bases to the left of the start of transcription
d. 8 to 10 bases upstream of the coding strand
e. C and D
e. C and D
During which phase is the sigma factor released?
Elongation
Which of the following is true about RNA polymerase?
a. It does not require a primer.
b. It has inherent DNA-DNA helicase activity.
c. It has no nuclease activity.
d. All of the above.
d. All of the above.
Rho-dependent termination is characterized or is associated with which of the following?
a. C-rich regions near the 3’ end
b. RNA-DNA helices activity
c. Hairpin turn
d. A and B
d. A and B
Rho-independent termination is associated with which of the following?
a. C-rich regions
b. G-C rich regions
c. Weak U-A regions
d. B and C
d. B and C
What drug suppresses the initiation step in Mycobacterium tuberculosis by binding to the beta subunits of RNA polymerase?
Rifampin
What drug binds to the DNA-RNA complex which results in the inhibition of strand elongation?
Dactinomycin
Acetylation of lysine residues is mediated by which enzyme?
Histone acetyltransferases
The action of histone acetyltransferases results in what chromatin structure?
Euchromatin
What enzyme restores the positive charge of lysine to increase its interaction with the chromatin strand?
Histone deacetyltransferases
Restoration of the positive charge of lysine results in what chromatin structure?
Heterochromatin
DNA methylation:
a. Promotes transcription
b. Inhibits mRNA production by blocking transcription factors
c. Removes the positive charge from lysine
d. Results in a polypeptide chain
b. Inhibits mRNA production by blocking transcription factors
What are the two sequences found in the eukaryotic promoter region?
TATA Box or Goldberg-Hogness Box
CAAT Box
Which of the following pertains to the CAAT Box?
a. 5’-GGCCAATCT-3’
b. 5’-ATATAAAA-3’
c. -25 region
d. -70 region
e. A and D
e. A and D
TATA Box is located in what region?
-25 region
What is the equivalent of the alpha subunit in eukaryotic transcription?
TFIID
What enzyme is responsible for the synthesis or large rRNA in the nucleolus?
RNA polymerase I
What enzyme synthesises mRNA from a DNA template strand?
RNA polymerase II
What enzyme produces tRNA?
RNA polymerase III
Which RNA polymerase is strongly inhibited by alpha-amanitin?
RNA polymerase II
Which RNA polymerase is inhibited by alpha-amanitin only in high concentration?
RNA polymerase III
Which RNA polymerase i unaffected by alpha-amanitin?
RNA polymerase I
True or False: Pre-rRNA undergoes modification through cleavage.
True
Which of the following are examples of tRNA modifications?
a. Intron removal
b. Trimming of 5’ and 3’ ends
c. Addition of certain sequences at the 3’ end
d. Modification to unusual bases
All of the above
What enzyme facilitates the addition of a 7-methyl-guanosine triphosphate cap?
Guanine-7-methyltransferase or guanylyltransferase
What enzyme facilitates the addition of the poly-A tail?
Polyadenylate polymerase
What is the function of 5’ capping
Protection
Recognition
What disease results from antibodies attacking snRNPs?
Systemic Lupus Erythematosus (SLE)
What disease results from aberrant splicing of the beta-globin mRNA?
Beta-thalassemia
