🧬protien And Stuffs Prt1 Flashcards
Central dogma
Gene expression
Protien synthesis
Dna to RNA to protiens
Transcription
Makes all types of rna
DNA characteristics
Deoxyribose at 2prime
ACGT
Double stranded
RNA characteristics
Has o at 2prime
ACGU
Single stranded (can make looping structures)
Start codon
AUG which codes to methionine protein.
Beadle Tatum experiment
One gene for every enzyme
(DNA for one RNA is true)
Took a mold and looked to see what it needed to grow.
With complete diet it grows
With restrained it died
It only grew with the vitamins so they concluded it was a vitamin
Separated out the vitamins and found it needed Niacin
Columns for pathway
(Most +)
Most + is first
Most - is the end
Rows for pathway
(Nutrient)
Most - is first
Most + is last
Major steps of transcription
Initiation
Elongation
Termination
Prokaryotes
Transcription
Initiation
DNA promoter sequence with a promoter protein
Promoter sequence (-35 and -10”tata box”) +1 is where transcription starts
Sigma factor protien attaches to promoter regions to flag down rna polymerase 2
Sigma + poly = holoenzyme
Elongation both (transcription)
Poly reads 3 to 5 and
Synthesis 5 to 3
All rna types
Rna is the same as the nontemplate strand of dna or coding strand
Prokaryotes termination
Rho independent (transcription)
No rhoprotien
Lots of c and g in a large sequence create hair pin loops in the rna and those bump the rna off of the dna and poly
Prokaryotes termination
Rho dependent (transcription)
Sequence in dna triggers a rut patch in rna which makes it so a Rho protien attaches to the end of the rna strand
It cathches up to the polymerase as it gets to the end of the protien and bumps it off the strand separating the rna from the dna and the poly
Eukaryotes initiation (transcription)
Promoter protien: transcription factor/inciation protiens / complex
GC box
Octamer box
Tata box
Has enhancer and silencer protiens that can activate certain genes in specific cells
Eukaryotes elongation for transcription exception difference
There are 3 types of rna polymerase for making different types of rna
We care about type 2 because it makes pre mRNA
Termination for eukaryotes transcription
It’s complicated you don’t really need to know. polymerase falls off
Rna processing
Only happens in eukaryotes
Turns pre mRNA into mRNA ready to leave the nucleus
Transcription and translation coupling
Only in prokaryotes
Dna is transcribing rna and at the same time ribosomes attach to the rna and begin translation making polypeptides
Things that are important for making pre MRNA into mRNA
5’ guanine cap
3’ poly a tail
Intro. Splicing
5’ G captain
Adds a 5’ - 5’ bond
Of the guanine
(Backwards)
Ends up with 3 phosphates
Protects mRNA from nuclease
It lets guards know that it is good to leave
3’ poly A tail
50-250 adenines normal to create a long tail
Rna stability/protection
Ribosome recognition.
Helps guards know it’s ready to leave
Intron splitting
Introns are taken out by splyisome and then the exons are then spliced together (this can happen differently which can create variation)
Start codon in exon1
Stop codon in last exon
Before codon 1 is there the 5’ untranslated region
And after the last exon is the 3’ untranslated region
Spliceosome
Made up of SnRNP
Protiens and SnRNA
And the intron RNA
Beginning of intro is labeled as GU
End is AG
Adenine found in the middle
SnRA binds to Gu and AG
And loops the GU so it is bound with the middle a
Splicisome snips at both ends and pulls the exons together taking out the intron
Exon shuffleing
Alternative splicing
We can Reaarange exons making different protiens from the the sequence of RNA which allow for greater diversity without changing the sequence
