Unit 2.2: DNA Transcription Flashcards
The process wherein a strand of DNA is converted into RNA.
Transcription
True or False: Ribosomes cannot read DNA.
True
DNA Transcription was discovered by who?
Francis Creek
True or False: DNA Transcription occurs in the genome, not the gene.
False (occurs in the gene only)
What is the first step to gene expression?
Transcription
What are the three major types of RNA?
rRNA
mRNA
tRNA
For transcription to occur, assistance from ______________ is needed to recognize the gene and dictate RNA polymerase where to begin transcription.
transcription factors
What are the three parts of a DNA during transcription?
Promoter Region
Structural Gene
Terminator Region
The region that dictates where transcription will start.
Promoter Region
This is the region located upstream of the structural gene. Also, this is the sequence of nucleotides that are recognized by the transcription regulation factors.
Promoter Region
What is the RNA Polymerase that acts on the Promoter Region?
RNA Polymerase I
Exons and Introns belong to which part of the DNA?
Structural Gene
These are the coding sequences of the structural gene.
Exons
This is the RNA created by RNA Polymerase I.
rRNA
The terminator region is composed of what RNAs?
rRNA
mRNA
tRNA
These are the non-coding sequences of the structural gene.
Introns
This is the RNA created by RNA Polymerase II.
mRNA
This is the RNA created by RNA Polymerase III.
tRNA
True or False: In transcription, only a particular gene in the genome is transcribed.
True
This can be compared to the set of instruction and ingredients needed in making a dish. It is a set of instructions / ingredients that are utilized by protein building machineries to build particular proteins.
mRNA
True or False: mRNA is the same for all cells within the body.
False
What acts as a hook / anchor in the promoter region of the gene being transcribed for prokaryotes?
Sigma Factors
The core enzyme has how many subunits? What are those?
5
2 Alpha
Beta
Beta Prime
Omega
True or False: Prokaryotes can synthesize mRNA, tRNA, and rRNA.
The core enzyme of a prokaryote is a protein in what structure?
Quaternart
The important enzyme in prokaryotes containing the core enzyme and sigma factor.
RNA Polymerase Holoenzyme
This binds to the promoter region of the gene, and then acts as a signal for the RNA polymerase where to start the transcription and what gene to transcribe in eukaryotes.
Transcription Factors
What RNA Polymerase works on snRNA?
RNA Polymerase II
What are the stages of DNA Transcription?
Initiation
Elongation
Termination
What are the three unique regions in the promoter region for eukaryotes?
TATA Box
GC Box
CAAT Box
This is the unique sequence of nucleotides in a gene that will allow the transcription factor and RNA polymerase to bind to the specific part of the DNA that needs transcription.
Promoter Region
True or False: Advantageous for survival as it prevents cells from overworking synthesizing all sorts of proteins at once.
True
This is where transcription starts. (counting)
+1
The GC box contains what sequence.
GGGCGG
Before transcription occurs, DNA strand should open up first since mRNA won’t be able to be transcribed. This process is called.
Elongation
What opens the DNA strand in transcription?
RNA Polymerase
What prevents the reannealing of the DNA strands in transcription?
RNA Polymerase
True or False: RNA polymerase has also its own intrinsic helicase activity.
True
The strand being read by the RNA polymerase in order to synthesize the new spread of RNA;Directs the synthesis of RNA.
Template Strand/Antisense Strand and Negative Strand
An RNA Polymerase in transcription acts like a (3)_________________ in DNA Replication.
SSBP
PRPC
Helicase
The strand’s sequence is the same as the RNA sequence that is produced with very little exception; it is also used to determine what amino acids are produced through mRNA.
Coding Strand
It is also known as the positive or sense strand.
Coding Strand
It is the strand complementary to the RNA.
Template Strand
RNA Polymerase moves along what strand?
Template Strand
Once RNA Polymerase synthesizes RNA, what will the polymerase add for adenine?
Uracil
An RNA polymerase inhibitor in eukaryotic cells; a toxin derived from a deadly fungus that we call Amanita phalloides (death cap), the cousin of Amanita muscaria.
Amanitine
An RNA polymerase inhibitor in prokaryotic cells; an antibiotic utilized in controlling bacterial infections
Rifampicin
The point in transcription wherein the RNA transcript is already made. At this point, the RNA is detached from the DNA so that it can be used by the ribosomes for protein synthesis. Also, this prevents the RNA polymerase from transcribing the rest of the DNA molecule.
Termination
Termination in eukaryotes occur when the RNA Polymerase starts synthesizing __________________.
Poly-adenylation Signal
What is the sequence of a poly-adenlyation signal?
TTATTT – Transcribed to AAUAAA
True or False: The RNA transcript that was synthesized in the previous steps can not be read by eukaryotic ribosomes immediately except for bacteria.
True
What is the end product of the transcription process in eukaryotes (not yet modified)?
Heterogenous Nuclear RNA (hnRNA)
The immature form of RNA that needs to undergo several modifications, particularly post transcriptional modifications, before it can be read by eukaryotic ribosomes and translated into proteins.
Heterogenous Nuclear RNA (hnRNA)
What are the three post transcriptional modification?
Splicing
Capping
Polyadenylation
What process is referred to below:
The 5’ end of the heterogenous nuclear RNA, there are triple phosphate groups. The triple phosphate groups are acted by the RNA Triphosphate by cleaving off one phosphate group.
Capping
What is responsible for cleaving off one phosphate group in the Heterogenous Nuclear RNA during capping?
RNA Triphosphotase
The two phosphates cleaved from the 5’ end during capping is called…
Pyrophosphate
What enzyme is responsible for cutting off the two remaining phosphate groups during capping?
Guanosine Monophosphate (GMP)
What enzyme separates the pyrophosphates?
Pyrophosphatases
After two phosphates are broken down by the Pyrophosphatases, what is the resulting enzyme?
Guanylyl Transferase
The last enzyme in capping that adds a methyl group on the GMP molecule, specifically by Nitrogen atom.
Methyl Transferase
What is the resulting nucleotide upon addition of methyl group to the GMP molecule?
5’ Methylguanosine Cap or 5’ Cap
This acts as a signal for initiation of translation and protects the hnRNA from nucleases.
5’ Cap/5’ Methylguanosine Cap
Poly-A tail
What post transcriptional modification occurs in the 3’ end of the hnRNA, where the OH group is found?
Polyadenylation Signal
What is the sequence of the polyadenylation signal?
5’ - AAUAAA - 3’
What enzyme recognizes the poly-adenylation signal?
poly-A Polymerase Enzyme
This is the process of removing non-coding areas in exons and introns.
Splicing
These are the molecules bound to proteins. These also remove introns.
Small Nuclear RNA (snRNA)
What are the 5 types of snRNA?
U1
U2
U4
U5
U6
These are molecules made up of snRNAs and protein units.
Small Ribonucleoproteins (SnRPs)
They cleave introns and stitch together exons.
Small Ribonucleoproteins (SnRPs)
What are the two major molecules of transcription?
RNA Polymerase
Transcription Factors
In splicing, what end is known as the splice site?
5’
