RNA overview Flashcards
What are the differences between RNA and DNA sugars?
RNA sugars have two OH’s
How does the extra OH group on RNA sugars effect the nucleotides?
make them less stable
Whats the difference between RNA and DNA bases?
RNA uses U instead of T (u is less stable)
RNA is synthesizes in which direction?
5’ to 3’
What performs transcription? How?
rna polymerase does, reads template dna in 3” to 5” direction and add nuceltides in 5” to 3” directions
RNA polymerase unwinds how many bp of dna at a time?
17
About how much of the human genome is protein coding?
1-2%
What does UTR stand for?
untranslated region
What does RBS stand for?
ribosome binding site
What are regulatory sequences in DNA? Do they get transcribed?
are regions that determine where and when the protein coding region will be transcribed (like in what tissue and what time), no they don’t get transcribed
Does only the protein coding region get transcribed?
No, UTRs and introns, and RBS and terminators get transcribed
Do prokaryotes have introns?
no
What is an exon?
is included in mature RNA and translated to proteins
What happens to introns during translation?
get spliced out
What is the splicing machinery?
the spliceosome
How does the spliceosome work?
It recognizes specific nucleotide sequences at the junction of exons and introns
Introns begin with what and end with what?
Begin with GU and end in with AG
What is the +1 site in dna?
Where transcription starts, rna polymerase recognizes the promoter here
Whats the -1, -2, -3 site? what about the 1,2,3 site?
Is the diff position upstream after the promoter. Positive values are downstream of the promoter
What are promoters?
They position RNA polymerase for transcription
What is the sense strand?
Is the 5” to 3” strand, is also referred to as the coding strand
What is the antisense strand?
Is the noncoding strand 3’ to 5’, promoter isnt here, also called the template strand where transcriptions builld ofof of
What is the promoter sequences in all E.coli genes importance?
Sequences in the promoter (-35 and -10 regions) position the RNA polymerase for initiation of
transcription in E. coli
What is quantitative PCR?
A method of PCR that allows us to quantify the amount of
DNA in the original sample
What is the gold standard for covid 19 testing?
qPCR
Does fluorescence increase as dna gets amplified?
Yes, after every cycle
What is a CT value?
Cycle number at which the fluorescence
level crosses the threshold
Say one sample crossed threshold at CT 2 and the other did at Ct 34, which one has more dna in the original sample?
the staple that crossed the threshold at CT 2
How do we use qPCR to monitor gene expression?
We convert mRNA to cDNA and then do pcr and incorporate dye.
What is cDNA? How do you make it?
Is complimentary DNA, made by using enzyme reverse transcriptase on mrna
You get a higher Ct value for one gene using cDNA, what does that mean?
That gene has higher expression (is transcribed more)
