Intro To Control Of Gene Expression Flashcards
How many genes are in the human genome?
50,000
How many genes are expressed in any given cell?
10,000
How is gene expression tightly regulated In time?
- development (embryos vs adults)
- in response to hormones infections or other signals
How is gene expression tightly regulated In space?
Different cells/tissues express different genes
What happens when gene expression isn’t regulated in metabolism?
Metabolic disease
What happens when gene expression isn’t regulated in cell shape/ motility?
Metastasis
What happens when gene expression isn’t regulated in cell differentiation?
Congenital disorders
What happens when gene expression isn’t regulated in cell proliferation?
Cancer
What is a metastasis
Movement of cells from one place to another
What cells can totipotent cells produce?
Any cell in the organism
What cells can pluripotent cells produce?
Cant produce placenta cells
What cells can blood stem cells produce?
Red blood cells, platelets and white blood cells
What does stem cell therapy do?
Reprograms the cells to become pluripotent
What is beta thalassaemia?
A group of genetic disorders caused by insufficient expression of beta globin
What is the big goal for stem cell therapy?
- to isolate adult stem cells from all developmental compartments
- the ability to drive these cells to develop either in vivo or in vitro in a completely controlled manner
Give some examples of translational control
- early embryogenesis
- environmental stress
What is early embryogenesis?
during the first 4-8 cell divisions there is no gene expressions. The first genes to be expressed is due to up-regulation of translation from more formed mRNAs
How does environmental stress exhibit translational control?
Exposure to heat shock or pathogens can cause global changes in translation
How are intracellular iron levels translationally controlled?
Ferritin binds iron and retains in the cytoplasm as a store for excess
How many miRNAs are transcribed by RNA polymerase II?
Over 500
What do miRNAs control?
The post transcriptional regulation of as many as one third of all human genes
How do miRNAs work?
They search for a complementary target mRNA.
Extensive match = its rapidly degraded
Less extensive match = translation reduced- mRNA sequestered and eventually degraded
