Lecture 1 Flashcards
Why does orientation of the locus matter?
During transcription RNA polymerase reads the template DNA strand in a 3-5 direction. If the promoter is behind the gene, or if they are not co-directional the gene expression will vary.
Give examples of when the expression of a locus will oscilliate
For example during the carcadian rythm and the sleep cycle.
What does penetrance mean?
How many procent of individuals carrying an allele will express the phenotype
What does expressitivity mean?
To which degree the indevidual is expressing the phenotype, for example how strong the color on a flower is.
What are a Topologically Associating Domain and what is it’s function?
TAD is a 3D loop structure that leads to a high interaction frequency within the domain and limits the interaction to outside genes by isolating the enhancer and the promoter to inside the domain.
What is an operator?
It’s a gene sequence that contains the code necessary to begin trancrition. When binding the operator is called operon.
What is a promotor?
A gene sequence that inititiates transcription downstream.
What is an enhancer?
A DNA sequence that increase transcription of genes and it’s not necessaryly close to the gene it enhances but the DNA structure can change to bring the enhancer to gene seuences that needs to be enhanced.
What is a repressor?
They bind to the operator and block transcription factors. Is used for gene regulation.
What is an activator?
It’s a transcription factor that increases and in some cases start the transcription of genes.
What is an insulated neighberhood and what does it do?
Chromatin loops isolating genes(one or more) with 2 CTCF homodimers cobound with cohesin which forms an anchor. It controls gene regulation, and can both enhanince or repress gene expression. Many tumors can be linked to deletion of the anchor which disrupts the gene regulation.
What is RIT?
Random integration of transgenes is inserting a gene randomly in the genome. It will be highly affected by where it ends up located and can give a big variation of gene expression dependng on the location of the gene.
What are the advantages of RIT?
It’s easier, can give higher then normal expression patterns and it makes it possible to study the transgene in relation to the native genes.
What are the advantages of gene targeting?
It’s more specific and can be replicated and the data can then be compared over multiple subjects.
