Intro To Control Of Gene Expression

Question 1

How many genes are in the human genome?

Answer 1

50,000

Question 2

How many genes are expressed in any given cell?

Answer 2

10,000

Question 3

How is gene expression tightly regulated In time?

Answer 3

• development (embryos vs adults)

- in response to hormones infections or other signals

Question 4

How is gene expression tightly regulated In space?

Answer 4

Different cells/tissues express different genes

Question 5

What happens when gene expression isn’t regulated in metabolism?

Answer 5

Metabolic disease

Question 6

What happens when gene expression isn’t regulated in cell shape/ motility?

Answer 6

Metastasis

Question 7

What happens when gene expression isn’t regulated in cell differentiation?

Answer 7

Congenital disorders

Question 8

What happens when gene expression isn’t regulated in cell proliferation?

Answer 8

Cancer

Question 9

What is a metastasis

Answer 9

Movement of cells from one place to another

Question 10

What cells can totipotent cells produce?

Answer 10

Any cell in the organism

Question 11

What cells can pluripotent cells produce?

Answer 11

Cant produce placenta cells

Question 12

What cells can blood stem cells produce?

Answer 12

Red blood cells, platelets and white blood cells

Question 13

What does stem cell therapy do?

Answer 13

Reprograms the cells to become pluripotent

Question 14

What is beta thalassaemia?

Answer 14

A group of genetic disorders caused by insufficient expression of beta globin

Question 15

What is the big goal for stem cell therapy?

Answer 15

• 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

Question 16

Give some examples of translational control

Answer 16

• early embryogenesis

- environmental stress

Question 17

What is early embryogenesis?

Answer 17

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

Question 18

How does environmental stress exhibit translational control?

Answer 18

Exposure to heat shock or pathogens can cause global changes in translation

Question 19

How are intracellular iron levels translationally controlled?

Answer 19

Ferritin binds iron and retains in the cytoplasm as a store for excess

Question 20

How many miRNAs are transcribed by RNA polymerase II?

Answer 20

Over 500

Question 21

What do miRNAs control?

Answer 21

The post transcriptional regulation of as many as one third of all human genes

Question 22

How do miRNAs work?

Answer 22

They search for a complementary target mRNA.
Extensive match = its rapidly degraded
Less extensive match = translation reduced- mRNA sequestered and eventually degraded