-
A gene is defined as...
a segment of DNA that is used to make a functional product, either an RNA molecule or a polypeptide.
-
Transcription is the act of...
"making a copy"
-
In Transcription, you synthesize ____ from ____.
RNA from DNA
-
Transcription adds nucleotides to...
the growing 3' end of an RNA chain
-
In DNA, a promoter is...
The site for RNA polymerase binding.
-
What signals the begining of transcription?
Promoter
-
What signals the end of transcription?
Terminator
-
What is the three steps in the "central dogma" of genetics?
- 1) DNA Replication
- 2) Transcription
- 3) Translation
-
DNA replication produces..
Chromosomal DNA
-
Chromosomal DNA stores....
information in units called genes
-
Trancsription produces..
Messenger RNA
-
Messenger RNA is a...
temporary copy of a gene that contains information to make a polypeptide
-
Translation produces..
A polypeptide
-
Polypeptides become a part of...
functional protein that contributes to an organism's trait
-
List the flow os genetic infromation in the central dogma of genetics from start to finish.
- 1) DNA Replication
- 2) Chromosomal DNA
- 3) Transcription
- 4) Messenger RNA
- 5) Translation
- 6) Polypeptide
-
What is gene expression at the molecular level?
The overall process by which the information within a gene is used to produce a functional product.
-
What causes RNA synthesis to occur within a defined location?
The promoter and terminator sites
-
What are the regulatory sequences of DNA?
sites for binding of regulatory proteins.
-
What is the role of regulatory proteins?
to influence the rate of transcription.
-
The DNA strand that is copied is termed the...
Template Strand (non coding)
-
The opposite DNA strand is called the...
Coding strand (sense strand)
-
The base sequecne of the coding strand is _________ the RNA transcript
identical to
-
RNA Polymerase is..
The enzyme that catalyzes the synthesis of RNA
-
in a transcription bubble there is about ____ bp of DNA/RNA hybrid.
8
-
In a transcription bubble there is about ____ bp of unpaired DNA.
17
-
What is a core enzyme?
a RNA Polymerase without the sigma factor
-
What are the four subunits of the core enzyme?
two alphas, A beta and a beta prime (a2bb')
-
In addition to the four subunits, what are the two other subunits that the core enzyme may include?
δ and ω (delta and omega)
-
What is capable of transcribing DNA into RNA randomly?
Core enyzme
-
The core enzyme is capable of transcribing DNA into RNA......
randomly
-
What is a holoenzyme?
A holoenzyme is a core enzyme with an added sigma factor
-
What is specificity?
When the subunit allows RNA polymerase to recognize promoters
-
Core enzyme does not recognize...
promoters
-
What are the three stages of transcription?
- Initiation
- Elongation
- Termination
-
What happens in Intiation?
The promoter functions as a recognition site for initiation
-
What happens in Elongation?
RNA polymerase slides along the DNA in an open complex to synthesize the RNA transcript in the 5’ to 3’ direction
-
What happens in termination?
A termination signal is reached that causes RNA polymerase to dissociated from the DNA.
-
In intiation, Following the binding of RNA polymerase to the promoter, the DNA is..
denatured into a bubble known as the open complex.
-
Promoters are DNA sequences that __________ gene expression.
"promote"
-
Promoters direct the exact location for the initiation of transcription by....
telling RNA polymerase where to bind on the DNA
-
_________ direct the exact location for the initiation of transcription by telling RNA polymerase where to bind on the DNA
promoters
-
The position in DNA where the RNA chain starts is called...
+1
-
DNA 5' to the start site is called..
Upstream
-
DNA 5' to the ________ is called Upstream.
start site
-
______ to the start site is called upstream.
DNA 5'
-
Upstream is given ______ values.
Negative
-
Downstream is given _____ values
Positive
-
DNA to the 3' side is called ....
downstream
-
DNA to the ____ side is called downstream.
3'
-
The sigma subunit recognizes the ____ and the ___ regions of a promotoer on both DNA strands.
-10 and -35
-
The sigma subunit recognizes the -10 and -35 regions of a promoter on....
Both DNA strands
-
what is the promoter region consists of from left to right?
-35 sequence, 16-18bp, -10 sequence
-
what is to the right of the promoter?
Transcriptional start site
-
The first nucleotide that acts as a template for transcription is located at the...
transcriptional start site
-
The first nucleotide that acts as a template for transcription is called...
+1.
-
The nucleotide that is immediately to the left of the +1 nucleotide is numbered..
–1
-
the nucleotide that is immediately to the right of the +1 nucleotide is numbered..
+2
-
There is no ____ nucleotide in the promoter numbering system.
zero "0"
-
The binding of the RNA polymerase to the promoter forms...
the closed complex
-
the open complex is formed when...
~17 bp of DNA in the vicinity of the TATAAT box is unwound
-
What is abortive initiation?
When Many short RNAs (2-10 nucleotides) are made within the open complex without any movement of RNA polymerase.
-
What is promoter clearance?
When RNA polymerase eventually moves away from the promoter 5’ to 3’
-
When is the sigma factor released?
when promoter clearance takes places
-
What marks the end of initiation?
When the sigma factor is released
-
What are the 4 steps of transcription initiation?
- 1) Binding of RNA polymerase holoenzyme to form a closed complex
- 2) Formation of an open complex
- 3) Release of sigma factor
- 4) Promoter clearance
-
RNA is snythesized in a 5' to 3' direction using _______ as a precursor
ribonucloside triphosphates
-
When RNA is snythesized, ______ is released.
pyrophosphate
-
why is pyrophosphate released when RNA is snythesized?
because ribonuceloside triphophates are used as a precursor
-
In the synthesis of the RNA transcript, The RNA polymerase slides along the DNA creating an ________ as it moves.
open complex
-
In the synthesis of the RNA transcript, The __________ slides along the ______ creating an open complex as it moves.
-
In the synthesis of the RNA transcript, The DNA strand known as the template strand is used to make....
a complementary copy of RNA as an RNA-DNA hybrid.
-
In the synthesis of the RNA transcript, The DNA strand known as the ___________ is used to make a complementary copy of RNA as an RNA-DNA hybrid.
template strand
-
In the synthesis of a RNA transcript, RNA polymerase moves along the template strand in a ________ direction.
3′ to 5′
-
What are the two different mechanisms for transcription termination?
Intrinsic termination and rho-dependent
-
Which transcription termination only requires sequences in the DNA -> RNA?
Intrinsic termination
-
Which transcription termination is factor independent?
Intrinsic termination
-
Which transcription termination is rho independent?
Intrinsic termination
-
Which transcription termination is rho dependent?
pho-dependent termination
-
Intrinsic termination depends on....
two sequences in the RNA
-
What are the two sequences in RNA that intirnsic termination depends on?
- 1) A uracil rich sequence located at the 3' end of the RNA
- 2) A stem-loop structure upstream of the Us
-
What acts as the recognition site for the binding of the rho protein?
a sequence upstream from the terminator, called the rut site.
-
What are the three steps in rho-dependent termination
- 1) rho-protein binds to the rut site in RNA and moves toward the 3' end.
- 2) RNA polymerase reaches the terminator and a stem-loop causes RNA polymerase to pause
- 3) RNA polymerase pauses due to its interaction with the stem-loop structure and the rho protein catches up to the open complex and separates the RNA-DNA hybrid
-
What happens in intrinsic termination?
The stem-loop causes RNA polymerase to pause and the U-rich sequence is not able to hold the RNA-DNA hybrid together. (termination occurs)
-
In intrinsic transcription termination, The DNA template strand goes through ________ to make RNA transcript.
Transcription
-
In intrinsic transcription termination, The DNA template strand goes through transcription to make .....
RNA transcript
-
In intrinsic transcription termination, the RNA transcript goes through _________ to make folded RNA.
Rapid RNA Folding
-
In intrinsic transcription termination, the RNA transcript goes through Rapid RNA folding to make...
Folding RNA
-
In intrinsic transcription termination, _______ helps cause chain termination
Folded RNA
-
In intrinsic transcription termination, Folded RNA helps cause....
chain termination
-
In bacteria, what event marks the end of the initiation stage of transcription?
The release of the sigma factor
-
A consensus sequence is...
is the calculated order of most frequent residues in nucleotides
-
An Up-promoter mutation is..
Any mutation allowing a mutated nucleotide in the core promoter sequence to look more like the consensus sequence
-
A down-promoter mutation is..
Any mutation allowing a mutated nucleotide in the core promoter sequence to look less like the consensus sequence
-
A mutation within a gene sequence changes the start codon to a stop codon. How will this mutation affect the transcription of this gene?
It won't
-
A mutation within a gene sequence changes the start codon to a stop codon. How will this mutation affect the translation? of this gene?
It will prevent the synthesis polypeptide synthesis
-
Sigma factor can slide along the _______ groove of the DNA.
major
-
How is the sigma factor able to recognize base sequences that are exposed in the major groove of the DNA?
Sliding along the najor groove
-
What happens when a sigma factor encounters a promoter sequence?
hydrogen bonding between the bases and the sigma factor protein can promote a tight and specific interaction
-
hydrogen bonding between the ____ and the sigma factor protein can promote a tight and specific interaction.
Bases
-
hydrogen bonding between the bases and the _________ protein can promote a tight and specific interaction.
Sigma factor
-
___________ between the bases and the sigma factor protein can promote a tight and specific interaction.
Hydrogen bonding
-
What is the sequence in Pribnow's box?
at the –10 region is 5ʹ–TATAAT–3ʹ
|
|
