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BCHM 4360 EXAM 2 NEWEST 2025 ACTUAL EXAM
COMPLETE QUESTIONS AND 100%CORRECT
DETAILED ANSWERS (VERIFIED AND GRADED A+|
NEWEST VERSION)
What is the main function of phosphorylation with regards
to RNA processing? - ANSWER-phosphorylation recruits
the RNA-processing enzymes, such as those that add a
guanosine cap to the 5' end of the mRNA
Capping leads to phosphorylation of the ______ ______ in
the CTD heptad repeat, which casues the polymerase to
______ elongation. - ANSWER-second serine, resume
What happens if there is an error in transcription? -
ANSWER-The DNA-RNA duplex could be distorted,
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causing stalling of the RNA Polymerase. The elongaton
complex can backtrack and transcription cleavage factors
can then chop off the 3' protruding RNA by enhancing the
endonuclease activity of RNA Polymerase, and
transcription can resume
What are two transcript cleavage factors in bacteria and
what is the transcript cleavage factor in eukaryotes? -
ANSWER-GreA and GreB, TFIIS
Within which region of RNA Polymerase do transcript
cleavage factors bind within? - ANSWER-funnel region
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What is a proposed mechanism for how transcript
cleavage factors work? - ANSWER-Transcript cleavage
factors are thought to position a metal ion at the active
site, which activates a water molecule for hydrolysis of the
phosphodiester bond
How doe eukaryotes solve the problem of nucleosomes
hindering RNA Polymerase? - ANSWER-use histone
chaperones to remove nucleosomes ahead of RNA
Polymerase, and reassemble them behind the polymerase
What are the three main histone chaperones in
eukaryotes? - ANSWER-FACT (Facilitates Chromatin
Transcription), Asf1, and Spt6
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Changes in supercoiling caused by the transcription
bubble could cause stalling of RNA Polymerase, and the
tension must be relieved by ______________. -
ANSWER-topoisomerases
What does Domain 2 of the RNA Polymerase holoenzyme
bind to and what is its function? - ANSWER--10 region,
helps separate duplex DNA (promoter melting)
What does Domain 3 of the RNA Polymerase holoenzyme
bind to and what is its function? - ANSWER-two bases of
the extended -10 region
BCHM 4360 EXAM 2 NEWEST 2025 ACTUAL EXAM
COMPLETE QUESTIONS AND 100%CORRECT
DETAILED ANSWERS (VERIFIED AND GRADED A+|
NEWEST VERSION)
What is the main function of phosphorylation with regards
to RNA processing? - ANSWER-phosphorylation recruits
the RNA-processing enzymes, such as those that add a
guanosine cap to the 5' end of the mRNA
Capping leads to phosphorylation of the ______ ______ in
the CTD heptad repeat, which casues the polymerase to
______ elongation. - ANSWER-second serine, resume
What happens if there is an error in transcription? -
ANSWER-The DNA-RNA duplex could be distorted,
,2|Page
causing stalling of the RNA Polymerase. The elongaton
complex can backtrack and transcription cleavage factors
can then chop off the 3' protruding RNA by enhancing the
endonuclease activity of RNA Polymerase, and
transcription can resume
What are two transcript cleavage factors in bacteria and
what is the transcript cleavage factor in eukaryotes? -
ANSWER-GreA and GreB, TFIIS
Within which region of RNA Polymerase do transcript
cleavage factors bind within? - ANSWER-funnel region
,3|Page
What is a proposed mechanism for how transcript
cleavage factors work? - ANSWER-Transcript cleavage
factors are thought to position a metal ion at the active
site, which activates a water molecule for hydrolysis of the
phosphodiester bond
How doe eukaryotes solve the problem of nucleosomes
hindering RNA Polymerase? - ANSWER-use histone
chaperones to remove nucleosomes ahead of RNA
Polymerase, and reassemble them behind the polymerase
What are the three main histone chaperones in
eukaryotes? - ANSWER-FACT (Facilitates Chromatin
Transcription), Asf1, and Spt6
, 4|Page
Changes in supercoiling caused by the transcription
bubble could cause stalling of RNA Polymerase, and the
tension must be relieved by ______________. -
ANSWER-topoisomerases
What does Domain 2 of the RNA Polymerase holoenzyme
bind to and what is its function? - ANSWER--10 region,
helps separate duplex DNA (promoter melting)
What does Domain 3 of the RNA Polymerase holoenzyme
bind to and what is its function? - ANSWER-two bases of
the extended -10 region
