Lecture 4 Flashcards
How is gene expression regulated at the level of transcription?
DNA is packed around chromatin, acetylation increases transcription
What are transcription factors?
Regulatory proteins that bind to specific sequences in DNA, which then promote transcription of the adjacent gene
Name something that mediates the expression of inflammatory genes?
NF-kappaB
How does oestrogen promote transcription?
Bind to oestrogen receptor which then acts as a transcription factor and binds to DNA
What is a limitation of TFs
They cannot directly transcribe DNA –> RNA. They create the conditions for it to start.
Describe another method of transcriptional control.
Alternative splicing of exons to form different proteins
What is VEGFA
Alternative splicing which generates isoforms of the same protein that have different functions.
What are microRNAs?
Non-coding regulatory RNAs, 22 nucleotides long. miRNAs regulate mRNAs.
What is a RISC
RNA Induces Silencing Complex
How do microRNAs regulate mRNA
Each miRNA can target several mRNAs as many mRNAs will have a number of miRNA attachment points.
What can measuring the amount of miRNAs present in the body tell us?
The origin of the disease by measuring the level of different circulating biomarkers in the blood.
Describe the PCR
A method that makes millions of copies of a short strand of DNA.
- DNA is denatured at 95C
- Primers anneal at 55C
- Extension phase 72C 5’ to 3’
- Multiple cycles
What are the components necessary for a PCR reaction?
Target DNA, Forward and reverse primers, Deoxynucleotide triphosphate and Taq polymerase
What are some applications of NGS (Next Generation Sequencing)
- Mutation detection - whole genome / exome targeted
- Pharmacogenetics - DNA modification
- Gene expression
- Microbiology
What are the impacts of NSG upon medicine?
Personalised medicine
