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MMBIO 240 Ch 15
MMBIO 240 Ch 15 EVANS
45
Microbiology
Undergraduate 1
04/05/2011

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Term
Eukaryotes have ___ types of RNA polymerase that differ in which types of RNAs which types of RNAs they transcribe and in the promoters they recognize
Definition
Three
Term
RNA polymerase II contains how many subunits? Are they all unique to this enzyme
Definition
12, some of them are, but some are also in the other polymerases
Term
The RNA poly II has what
Definition
One or more discrete elements
Term
RNA polymerase II requires what for specific transcription from a promoter
Definition
General transcription factors
Term
To identify the transcription start site what tools would you need?
Definition
S1 mapping, primer extension, and run-off transcription.
Term
What tools can be used to measure gene activity?
Definition
S1 mapping and primer extension
Term
__ ____ provide another means for measuring the level of gene expression.
Definition
Reporter genes
Term
RNA polymerase II requires what general transcription factors for transcription
Definition
TFIIA, B, D, E, F, and H must bind to the promoter
Term
How does preinitiation begin
Definition
The TFIID or TBP binds to the promoter, and the complex formation begins. The TBP contacts the TAT box, and the TAFs contact other promoter elements.
Term
After the preinitiation complex has begun, in what is added in the correct order
Definition
TFIIA, TFIIB, TFIIF-RNA poly II complex, TFIIE, and finally TFIIH
Term
alpha amanitin
Definition
is a cyclic peptide of eight amino acids. It is an inhibitor of RNA poly II (which is why it is a deadly toxin). Can also be used to to determine which types of RNA poly are present. RNA I is insensitive to it, II is highly sensitive, and III is slightly sensitive.
Term
basal transcription
Definition
Are typically defined as the minimal complement of proteins necessary to reconstitute accurate transcription from a minimal promoter (such as a TATA element or initiator sequence) They are distinct from regulatory transcription factors, which bind to sequences farther way from the initiation site and serve to modulate levels of transcription.
Term
core promoter
Definition
is the minimal portion of the promoter required to properly initiate gene transcription. It contains a binding site for RNA poly I, II or III.
Term
CTD
Definition
Carboxyl terminal domain- (C Terminus) is the end of the amino acid chain terminated by a free carboxyl group.
Term
gel mobility shift assay
Definition
(EMSA) is a common affinity electrophoresis technique used to study protein-DNA or protein RNA interactions. Performed in vitro concurrently with DNase footprinting, and primer extension.
Term
general transcription factor
Definition
are protein transcription factors that have been shown to be important in the transcription of class II genes to mRNA templates. They form the preinitiation complex, which with RNA Poly II bind to and read the single stranded DNA gene template.
Term
primer extension
Definition
is a technique whereby the 5' ends of DNA or RNA can be mapped. It requires a a radiolabelled primer, which is complementary to a region near the 5' end. It is allowed to anneal to the RNA and reverse transcriptase is used to synth. cDN until it reaches the 5' end of the RNA. It is then run on a polyacrylamide gel allowing for determination of the transcriptional start site.
Term
reporter gene
Definition
is a gene that researchers attach to a regulatory sequence of another gene of interest in cell culture, animals or plants. A plasmid is a reporter gene, luciferase, green fluorescent protein, the lacZ gene,
Term
RNA poly I
Definition
the only enzyme that transcribes ribosomal RNA.
Term
RNA poly II
Definition
This catalyzes the transcription of DNA to synthesize precursors of mRNA and most snRNA and microRNA.
Term
RNA poly III
Definition
transcribes DNA to synthesize tRNA and small RNAs. The genes that it transcribes fall into the category of housekeeping genes-is tied to the regulation of cell growth
Term
run off transcription
Definition
tells us two things- where transcription initiates and how much of this accurate transcription occurred.
1-Start with DNA, cut it up with restriction enzyme
2-transcribe the fragments
3-measure the length of the run off transcript
Term
S1 mapping
Definition
A probe is prepared and allowed to attach to the mRNA. S1 then digests anything that is not anealled,
Term
TAF
Definition
Term
TATA binding protein (TBP)
Definition
is a transcription factor that binds specificially to a DNA sequence called the TATA box. The DNA sequence is about 35 base pairs upstream of the transcription site
Term
TATA box
Definition
is a DNA sequence (cis-regulatory element) found in the promoter region of genes in archaea and eukaryotes. It is considered to be the core promoter sequence, it is the binding site of either general transcription factors or histones, and is involved in transcription.
Term
TBP associated factors (TAFS)
Definition
These are the subunits that make up TFIID (there are 16). These add promoter selectivity, especially if there is no TATA box sequence for TBP to bind to.
Term
TFIIA
Definition
interacts with the TBP subunit of TFIID and aids in the binding of TBP to TATA box containing promoter DNA. Although it does not recognize DNA itself, its interactions with TBP allow it to stabilize and facilitate formation of the preinitiation complex. Results in the exclusion of negative (repressive) factors.
Term
TFIIB
Definition
This localizes to the nucleus where it forms a complex with the transcription factors IID and IIA. Serves as a bridge between IID and RNA poly II
Term
TFIIB-recognition element (BRE)
Definition
This is a core promoter element that is recognized by TFIIB. The selected sequences contain a strong representation of G and T bases and a striking preference against A. Contact takes place via the minor groove.
Term
TFIID
Definition
this is a form of eukaryotic RNA poly II that is recruited to the promoters of protein coding genes in living cells. Consists of RNA poly II, a subset of general transcription factors and regulatory proteins (SRB proteins). It binds to the TATA box
Term
TFIIE
Definition
Is thought to be involved in DNA melting at the promoter, contains a zinc ribbon motif that can bind single stranded DNA
Term
TFIIF
Definition
DNA is thought to be wrapped one complete turn around the preinitiation complex, and TFIIF helps keep this tight wrapping. May also aid in forming the transcription bubble. Most similar to bacterial sigma factor.
Term
TFIIH
Definition
Has helicase and ATPase activities and help create the transcription bubble-also involved in nucleotide excision repair
Term
RNA poly I creates ____, RNA poly II creates _____, RNA poly III creates _____?
Definition
rRNA, mRNA, tRNA
Term
What is not a common characteristic of nucleotide sequence elements within eukaryotic core promoters?
Definition
They are not uniform in structure and position within all actively transcribed genes
Term
The protein complex(es) required for recognition of the core promoter and binding of the core promoter by RNA polymerase II is (are) called?
Definition
Basal apparatus
Term
The initial placement and interaction of TBP within the minor groove of DNA and the interaction of TBP with other transcription factors is facilitated by a set of proteins called what?
Definition
TAFs
Term
The CTD tail of RNA polymerase II does what?
Definition
requires phosphorylation for promoter clearance and progression through transcription.
Term
Promoters are cis acting. The promoter is considered a cis-acting site because:
Definition
it exclusively influences the expression of a gene that it is proximal to.
Term
Transcriptional activators do what?
Definition
They regulate the specificity and efficiency with which a promoter is recognized by RNA polymerase.
Term
Eukaryotic RNA polymerases can be distinguished by their sensitivities to ____-
Definition
alpha amanitin
Term
Pre-initiation beings with either ______ or TATA binding protein to the core promoter
Definition
TFIID
Term
The C terminal domain of the largest RNA polymerase subunit must be _____ for chain elongation to occur.
Definition
phosphorylated
Term
What is the process called when foreign DNA is introduced into a eukaryotic cell
Definition
Transfection
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