MODULE 3 Flashcards
Steps of Transcription (3)
____ occurs when enzyme in RNA polymerase binds to a region of a gene called the promoter. DNA unwinds and enzyme can now read the bases.
____ addition of nucleotides to the mRNA strand
____ it detaches from DNA, mRNA strand is complete afterwards
Initiation
Elongation
Termination
Who coined the term Central Dogma which explains the flow of genetic information?
Francis Crick
Types of strand (2):
ANTISENSE strand -
SENSE strand -
Template strand
- the RNA molecules will be complementary and antiparallel to this strand
Non-template strand
COOKBOOK =
CHEF =
RECIPE =
INGREDIENTS =
PIZZA =
COOKBOOK = DNA
CHEF = RIBOSOME
RECIPE = mRNA
INGREDIENTS = AMINO ACID
PIZZA = PROTEINS
START codon
AUG
STOP codon
UAA
UAG
UGA
____ coding for a protein
GENE EXPRESSION
Considering there are millions of base pairs in a chromosome.
How many bp in a gene?
10 - 50 Kbp
____ aims to make an RNA copy of a gene’s DNA sequence. A process where RNA molecules are synthesized from DNA templates.
It makes a protein-coding gene, the RNA Copy, or ____ which carries the information needed to make a ____ unit
Transcription
transcript
polypeptide unit
Where does transcription occur for eukaryotes?
Where does it occur for prokaryotes?
Nucleus
Cytoplasm
Transcription is catalyzed by the enzyme ____ for both prokaryotes and eukaryotes
It needs three major components for the process:
RNA polymerase
It needs three major components for the transcription process:
- DNA template
- the Substrate (raw material)
- The transcription apparatus
_____ a stretch of DNA that encodes an RNA molecule and the sequences necessary for its transcription.
It has (3)
The transcription unit
- Promoter
- RNA-coding region
- terminator
_____ a DNA sequence that initiates and TRANSCRIPTION APPARATUS recognizes and binds. Determines the DNA strand to be read as template + the direction.
_____ a sequence of DNA nucleotides copied into an RNA molecule
_____ a sequence of nucleotides that signals where transcription is to end. Transcription stops when it is copied to RNA
Promoter
RNA-coding region
Terminator
What is the substrate for transcription?
Nucleotides are added where?
ribonucleotide triphosphates
3’ -OH
What kind of structures forms in RNA for termination?
hairpin structure
TYPES OF RNA POLYMERASE:
RNA polymerase I - located in the ____, which ___ is transcribed processed and assembled into ___.
RNA polymerase II - located in the ____, and synthesizes all ____
RNA polymerase III - located in the ___, transcribes ___ and ____
nucleolus
rRNA
ribosomes
nucleus
pre-mRNAs
nucleus
pre-tRNAS
nuclear pre-RNAs
Differences between bacterial and eukaryotic transcription
- DNA exists as _____ which is why it must be opened
- Bacteria have ___ RNA pol only
- Bacteria have ___ which recognizes and binds directly to promoter
- In eukaryotes, promoter recognition is carried out by ____ which bind to the promoter.
- Eukaryotes have extra ____ many kilobases away from the transcription start site
chromatin
one
holoenzyme
accessory proteins
regulatory sequences
_____ Term for any protein required to initiate or regulate transcription in eukayotic cells
There are two types:
____ General factors that participate in the transcription-initiation complex
____ Specific factors that stimulate or repress transcription of particular genes by binding to the regulatory sequences
Transcription Factor
There are two types:
BTF - Basal Transcription Factors
TAP - Transcriptional activator proteins
_____ consensus sequence in the promotor region of eukaryotic genes that binds to a general transcription factor.
____ The basal transcription factor that binds to the TATA box.The transcription factor that specifies the position at which transcription is initiated.
TATA BOX
TATA - binding protein (TBP)
_____ Protein complex that moves histones out of the way of the DNA template.
It will replace them again later.
FACT “Facilitates chromatin trasncription”
What do you add to pre-MRNA?
____ protects mRNA in the cytoplasm and helps in the attachment of mRNA with ribosome for translation. It is made up of a ____(____)
____ with the process of ____ it signals the end of mRNA, it has a lot of Adenine bases. Helps with the stability.
____ is when sections of INTRONS are removed and the EXONS stuck together by ____ or a complex____
5’ cap
GTP (Guanosine triphosphate)
3’ polyadenylation tail
polyadenylation
splicing
snRNPs
spliceosome
Steps of pre-mRNA splicing (3)
The ____ loops out as ____ bind together to form a ____
The ___ is ___ and the ____ are spliced together
The resulting ____ can then exit the ___ to be translated in the cytoplasm
The INTRON loops out as snRNPs bind together to form a SPLICEOSOME
The intron is excised and the exons are spliced together
The resulting MATURE mRNA may then exit the NUCLEUS to be translated in the CYTOPLASM
Termination of RNA chain synthesis is brought about by two type of mechanisms:
_____ also called ____ is a mechanism that causes mRNA transcription to be stopped. The mRNA has a sequence that can base pair with itself to form a ____ structure of ___ in length that is rich in ____
This is what causes the hairpin structure with ____ nucleotides in the 2nd inverted repeat and then a string of ____ nucleotides after the hairpin
Intrinsic Termination / Rho-independent termination
stem-loop structure
7-20 base pairs
cytosine-guanine base pairs
6 adenine
uracil
_____ where more than one mRNA can be made from the same gene
Alternative splicing
_____ the second part of the central dogma and is RNA to protein or Protein syntehesis. It occurs in the Cytoplasm.
After an mRNA leaves the ____ it goes to a ____
Translation
nucleus
ribosome
where does the mRNA leave through so it can bind to a ribosome?
What carries the individual amino acids to the surface of the ribosome so it can line up against a ____ with its ____?
_____ link the amino acids together to form ___ before the previous thing breaks away to pick up another amino acid.
Finally, the completed ____ detaches through the ____ to move into ____ to become a functional protein.
Nuclear pores
tRNA
complementary codon
anticodon
Ribosomal enzymes
peptibe bonds
polypeptide
Release factor
golgi apparatus
(a) _____
_____
(b) _____
_____
(c) _____
_____
(d) _____
____
____
____
(a) Transcription
RNA
(b) Post-Transcription
mRNA
(c) Translation
Polypeptide
(d) Post translation
Protein folds upon itself
Effector Molecule
Active Protein
