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Question 1

transcriptome

Answer 1

The sum of all RNA molecules produced by the genome machinery
● Prokaryotes only have 1 RNA polymerase complex
● Eukaryotes have 3 RNA polymerases + two organelle ones

Question 2

rna polymerase

Answer 2

RNA is based on ribose
RNA synthesis has 3 phases (no primer needed)
● Initiation (most regulated)
● Elongation
● Termination

Question 3

mrna

Answer 3

code for proteins

Question 4

rrna

Answer 4

part of ribosome

Question 5

trna

Answer 5

carries amino acids and puts the in right place for mrna and translates itno amino acid

Question 6

frequent transcriptase

Answer 6

Frequent one used is a leukemia variant, RT needs a primer with an OH group,
the copy RT makes can be called copy DNA (cDNA)

Question 7

rna poly where transcribe prokayotes?

Answer 7

● Subunits
1. 𝜶: Binds starting codon
2. 𝛽: Actually adds the nucleotides
3. 𝛽’: Binds the DNA template (so it doesn’t fall off)
4. ⍵: folds the 𝛽’ subunit
5. σ: Recognizes DNA promoter
● This subunit enables regulation of multiple gene sets.
● There are also anti-sigma factors that inactivate one or several
of them
● There are also anti-anti-sigma factors that can activate the
sigmas by inactivating the anti-sigma factors

Question 8

intiations

Answer 8

● Ribosome subunit 30S binds to the DNA strand at the initiation codon
thanks to two factors
● Initiation factor 2 accompanies methionine to the start codon
● IF1, 2 and 3 unbind from the complex, allowing the 50S subunit to
associate

Question 9

termination rho independant

Answer 9

Hair pin is made (on 5’ side)
● The hair pin slows down the RNA polymerase
● If paired with A=U rich DNA, the poly falls off

Question 10

termination rho dependant

Answer 10

● RNA still makes hairpins, this calls a rho factor
● The rho factor forms a ring shaped translocase
● Threads the RNA along the ring, when it catches up to polymerase,
it “kills” it

Question 11

rna ploly where dna transcribed eukaryotes?

Answer 11

rnap1, rnap3, rnap2

Question 12

rnap 1

Answer 12

● Makes rRNA, which lies in the nucleus, transcribing genes, and
makes up ribosomes.
● rDNA is a lot of repeated sequences

Question 13

rnap 3

Answer 13

● Makes tRNA, which needs to be spliced and matured after
transcribing DNA
● Also transcribes one type of rRNA genes

Question 14

rnap 2

Answer 14

● Makes primary RNA (RNA not matured yet)
● TBP and “General transcription initiation factors” look for promoters
and help binding

Question 15

enhancers

Answer 15

promote binding to promoter, but van be far away

Question 16

transcription factors

Answer 16

influence inhancers, promoters and loops

Question 17

introns

Answer 17

useless, non coidng

Question 18

exons

Answer 18

coding

Question 19

polyadenylate tail

Answer 19

aaaaaaaaaaaaaaaaaa is added to make sure its stable, if short rna can degrade

Question 20

splicing

Answer 20

● Splicing happens while RNA is being made
● After the cap is added, a collection of splicing enzymes (spliceosome) look
for a splice donor site(end of first exon), when found, looks for a splice
acceptor site(start of next exon).
● It will then glue these sites together
● The order of exons is determined by proteins that obscure the acceptor site

Question 21

capping

Answer 21

● Cap synthesizing complex makes the cap, due to this Cap binding complex
(CBC) is activated
● When CBC is activated, this is the first sign that splicing should happen
● The cap is a guanosine methylated in the 7th C

Question 22

prokayrote initioation

Answer 22

The 30S ribosome attaches to the RBS or Shine-Dalgarno sequence (just a
sequence of a lotta purines). Once bound, it scans for the start codon where all
the good stuff happens.

Question 23

eukaryotic intiation

Answer 23

There is no RBS, instead, the ribosome recognizes the 5’ cap structure of the
mRNA. The 40S ribosome binds to the 5’ cap with IF. After binding, the ribosome
scans for the start codon.

Question 24

TATA binding protein TBP

Answer 24

a transcription initiation factor, it is part of the ‘loaders’
of each of the three eukaryotic RNA polymerases, somewhat analogously to the sigma
subunit of the bacterial RNA polymerase

Question 25

eukaryotic rna polymerase II

Answer 25

makes primary rna transcripts that become mrna, starts at gene promoters,

Question 26

polyadenylase

Answer 26

elongates 3”OH cleaved rna, adds 80 to 250 A’s to 3’ end of mrna