The Nobel Prize for studying the molecular basis of eukaryotic transcription went to ______________________
Arthur Kornberg and Roger Kornberg
What did Arthur and Roger Kornberg study?
The molecular basis of eukaryotic transcription
What are the major differences in eukaryotic and prokayotic transcription?
-much larger eukaryotic genome
-nucleus and RNA processing (transcription and translation occur separately in eukaryotes)
-eutkaryotic genome organized into chromatin
Prokaryotic Polymerase transcribes ____________
Eukaryotic RNA Polymerase I transcribes ____________
Eukaryotic RNA Polymerase II transcribes ____________
mRNA, dnRNA, miRNA
Eukaryotic RNA Polymerase II trancribes ________________
How are human RNA polymerases I, II, and II similar in structure?
each has four subunits in common
RNA polymerase has ____ subunits
RNA Polymerase I has ___ subunits
RNA Polymerase II has ___ subunits
RNA Polymerase III has ___ subunits
Eukaryo'c RNA polymerase II: Activator prortiens bind to ___________
enhancer DNA elements
Eukaryo'c RNA polymerase II: ___________________ unpackage DNA
Chromatin remodeling complexes
TFII is made of ___ proteins
What is the sequence of Eukaryo'c RNA polymerase initiation?
1. Ac'vator proteins bind to enhancer DNA elements
2. Chroma'n remodeling complexes unpackage DNA
3. General transcrip'on factors bind
(TFII proteins (15 proteins) including TATA binding protein
4. RNA polymerase II core enzyme loads onto promoter
TATA box is located at ____
CAAT box is located at ____
Sequence of TATA box:
Sequence of CAAT box:
_____________ helps guide RNA pol II binding.
The first event in eukarytotic transcription.
binding of the TATA-binding protein (TBP) to the TATA box
Next step in transcription after TATA-bining.
TBP attracts other GTFs and RNA pol II core to promoter
TBP attracts GTFs and RNA pol II, creating _______
Order of Assembly of the preinitiation complex:
4. Pol II w/ CTD
Transcription Factor II
carboxyl tail domain
Order of Addition of molecules following the formation of the preinitiation complex
3. NTP (phosphorlation)
4. Release of general factors except TBP
The end of initiation and the beginning of elongation occurs when ________________
CTD is phophorylated, causing release of general factors (except TBP)
RNA processing enzymes are recruited by the ______________
CTS tail of RNA pol II
CTD is ___ copies of what sequence?
52 repeats of Tyr-Ser-Pro-Thr-Ser-Pro-Ser.
Structure of 5' cap
7-methylguanosine + three phosphate groups
Two functions of 5'cap
1. protects RNA from degradation
2. required for translation (recognized by ribosome)
What catalyzes the addition of the 5' cap to mRNA
capping enzymes - assisted by attachement to CTD
What does m7GpppX do?
Polyadenylation is performed by ___________
What is the importance of the phosphorylation of the CTD?
provides binding sites for processing enzymes and factors (capping, splicing, cleavge and polyadenylation)
Transcription continues until RNA pol II reaches what conserved sequences?
What happens what RNA pl II reaches AAUAAA
-cleavage occurs 10-35bp downstream
-Poly-A polymerase is activatde by phosphorylation and adds poly-A tail
What factors control cleavage and poly-adenylation?
Cleavage and polyadenylaton specificity factor
Cleavage s'mula'on factor
_____________binds to the Poly‐A tail
and contributes to transcript stability and helps
Poly‐A binding protein
Discovery of RNA Splicing was by _________
Chow and Roberts
What causes R‐loop hybridization
partial dnaturation of DNA - RNA diplaces DNA
What is the R-loop
displaced DNA strand
What is the GU-AG rule?
conserved target dinucleotides mark the 5' and
3' splice sites on an intron
How is an intron marked for plicing?
conserved target dinucleotides mark the 5' and
3' splice sites
Spliceosome forms a ________ shaped intermediate
What short sequences dictate where splicing occurs?
How many sequential cuts remove an intron?
Spliceosome is made of _____ snRNPs
Alpha tropomyosin is an example of ________________________
Alternative splicing can create multiple different mRNAs
_______________ can create multiple different mRNAs from a single gene
What is trans splicing?
Trans splicing can join exons from two different genes
___________ can join exons from two different genes
Who discovered that RNA can by catalytic/an emzyme?
Cech and Altman, independently
What experiement did Cech and Altman, perform?
Splicing occured in a test where no cell extract was added, only rRNA, Mg, and GTP, yet splicing still occured - RNA can be catalytic/an enzyme
What functional classes of RNA are found only in eukaryotes?
-siRNA? (possibly in prokaryotes)
What are the differences between eukarytotic and prokaryotic mRNA transcripts?
Prokaryotic mRNA is the primary transcript, has a 5' triphosphate end and no poly-A tail
=GTF general transcription factor
How do enhancers and activators interact?
enhancers are DNA sequences that may interact with protein activators bound to RNA pol II