8. gene expression Flashcards
crispr
genome editing
faster than previous methods
pharming
genetically modifying animals and plants to make useful products
gene therapy
fixing faulty genes
leukaemia
substitution in mutation
change in base sequence
nonsense substitution
early stop codon
short chain
mis-sense substitution
wrong amino acid being made
can effect tertiary structure
silent substitution
different base - same amino acid
degenerate nature
deletion/addition/duplication mutation
loss or gain of one more bases
changing whole future sequence
frame shift
apoptosis
when an organism kills a cell
stem cell define
cell which can divide an unlimited no. of times (highly potent)
totipotent stem cell
any type of body cell
‘embryonic’
only for limited amount of time in mammalian embryos
pluripotent stem cell
can differentiate into any embryonic cell
not extra-cellular (part of placenta)
unlimited no. of times
treat diseases
multipotent stem cell
adult stem cell
tissue growth and cell repair
unipotent stem cell
only into specific type of cell e.g. heart tissue/cardiomyoctes
oestrogen mechanism epigenetics
steroid hormone
moves into blood stream
binds to cell with specific complementary receptor
diffuses through PhosLip Bilayer (lipid soluble)
binds with transcription factors
activates it by releasing inhibitor
moves into nucleus and binds to promotor region of DNA
stimulates RNA polymerase
transcription factor
regulating protein
binds to promoter region
stimulates RNA polymerase
signals specific gene production
promotor region
DNA sequence that controls the transcription of a gene
upstream of the gene’s transcription start site
epigenetic
inheritable changes to gene function
no change to base sequence
environment stimulates methylation or prevents acetylation
DNA methylation
methylation of cytosine (next to guanine, CpG regions)
has to be in promoter region
transcription factor cannot bind
RNA polymerase doesn’t transcribe the gene
how can DNA methylation treat tumours/cancer
removal of methyl groups from tumour suppressor genes
allows gene to be expressed
regulate cell cycle
how can acetylation treat tumours/cancer
removal of acetyle groups from oncogenes
DNA raps more tightly
genes suppressed
oncogenes
stimulate cell division too quickly
conventional drug use as comparison
effective comparison
unethical not to treat
negative use of pluripotent cells
might differentiate to wrong type of cells
might be out of control
cancer/tumours
