Lec1HumanGeneTranscription Flashcards
What is POU1F1?
a transcription activator (transactivator) for GH, PRL and TSHs in ant pituitary gland
If POU1F1 is mutates, what occurs>
It leads to a decrease in GH, PRL, TSH (all hormones)
In the article related to pituitary hormone deficiency, the young patient had a severe decrease on GH, PRL, and TSH due to
heterozygous mutations (2 separate mutations on POU gene)
What are the heterozygous mutations that occurred for this pt?
- Deletion frameshift : deleted a base and it caused the reading frame to be different, so different amino acids) causing lacked DNA binding domain
- A missense mutation (diff protein) in the C-terminal
True or False RNA synthesis is transcription
True
What does every gene need for activation of transcription by RNA poly 2?
- every gene of ever cell has nonspecific proteins: to do PIC
- every gene of every cell has nonspecific elements: TATA seq,non specific DNA seq
nonspecific=every gene/cell has them
How is transcription activated the right time and right place?
every cell has SPECIFIC proteins/elements that allow for specific genes to be transcribed.
ex: liver cells has specific elements that create protein for specific liver function
_______ is the most efficient place to regulate
Transcription
RNA poly 2 transcribes
all protein-coding genes
RNA poly 1 transcribes
rRNA
All RNA polymerase has their own ____
PIC
RNA poly 2 has binding sites for ___ _____ which is why it is used for protein coding genes.
splicing factors
What is similar between RNA poly 1,2,3?
They all have their own PIC
TATA box is 4 NT. SSDBP recognizes 10 NT so we need to methylate H3K4. Why?
4NT is to small to recognizes to we methylate histone to create more binding sites to help recruit PIC
The TATA is too small for SSDNP to recognize so what do we do?
H3K4 methylation to help recruit PIC
What is TATA?
it is non specific and its present in almost all coding genes (10-20 bp upstream)
What is TFIIH?
It is non specific and has helicase activity and phosphorylates carboxyl end of RNA poly 2 (CTD) (HELICASE AND KINASE )
What is TFIID?
Contains a subunit that recognizes H3, K4 methlylation (post translational modification) AND has TBP to bind of TATA box (many subunit/polypeptide)
We need _____ nucleotide
triphosphate
What are some examples of non specific proteins, termed “general transcription factors” (GTFs)
TFIID, TFIIH, RNA poly 2
What binds to DNA?
Transactivators and TFIID (TBP specifically)
TF in TFIIX referes to
transciption factor
II in TFIIX refers to
RNA poly2
X in TFIIX refers to
any protein A-H
A kinase does what?
phosphorylates
What does TAF stand for?
TBP Associated Factors
The ____ subunit of TFIID recognizes _____ and binds the _____
TBP, H3K4, TATA
The ____ subunit of TFIID binds_____
TAF, other proteins
What represents the start of transcription?
TFIIH phosphorylates carboxy terminal domain of RNA poly2 (on serine 5)
What starts the PIC?
TFIID (TBP and TAF)
True or false TATA box is a specific DNA sequence at the start of every gene
FALSE (non specific DNA sequence) at the start of every gene
Most of the GTF’s assemble by interacting with
each other, NOT by contacting DNA
Transcription factors are the same as transactivators which are
proteins that activate transcription
What are the decoys?
TFIIF, TFIIE
Which subunit of TFIID recognizes the TATA box?
TBP
Which subunit of TFIID recognizes the other DNA sequences near the transcription start point, regulates DNA binding by TBP
TAF