Biosignaling

Question 1

What are the 4 components of signal transduction?

Answer 1

Signal
Receptor
Transduction pathway
Target

Question 2

What are the 3 groups of signals?

Answer 2

Soluble-freely move in aqueous
Linked-part of membrane
Physical-ie. Light/temperature

Question 3

What are the 7 canonical receptor families?

Answer 3

1-G-protein coupled*
2-receptor tyrosine kinase*
3-receptor guanylyl cyclase
4-ligand gated ion channel
5-adhesion
6-nuclear
7-cytokine

Question 4

What is Kd?

Answer 4

Dissociation constant

Represents concentration of ligand needed to bind 50% of the receptors.

A low Kd is indicative of a high binding affinity

Question 5

What are the 4 major roles of the membrane in signaling?

Answer 5

1-Receptor localization
2-Ligand exposure
3-Signaling complex formation
4-Endocytosis

Question 6

What two main types of signaling complexes are formed by the membrane?

Answer 6

Protein scaffolds

Signaling endosomes

Question 7

What are the two types of lipid rafts?

Answer 7

Caveolar-invagination

Planar

Question 8

What two affects can lipid rafts have on signals?

Answer 8

• Grouping components to promote signal

- separating components to inhibit signal

Question 9

What are the three endocytic pathways?

Answer 9

Clathrin dependent
Caveolin dependent
Independent of clathrin or caveolin

Question 10

What are the 3 ways signals are regulated by endocytosis?

Answer 10

Down regulation
Maintained
Generated

Question 11

What are three ways chemical reactions transfer information?

Answer 11

Complex formation/dissociation
Structural change
Post-translational modification

Question 12

What are the 7 most prevalent post translation modifications? (PUGOMAS)

Answer 12

1-Phosphorylation
2-ubiquitination
3-glycosylation
4-oxidation
5-methylation
6-acetylation
7-sumoylation

Question 13

What are the 4 common signaling cascades?

Answer 13

1-mitogen-activated protein kinase(MAPK)
2-Janus kinase (jak-stat)
3-phosphatidylinositol (PI3K)
4-phospholipase C (PLC)

Question 14

What growth factors are examples of MAPKKK in MAPK signaling?

Answer 14

A-raf
b-raf
C-raf-1
Mos
Tpl-2

Question 15

Which growth factor is an example of MAPKK in MAPK signaling?

Answer 15

Mek1/2

Question 16

Which growth factor is an example of MAPK in MAPK signaling?

Answer 16

Erk1/2

Question 17

What does PLC do?

Answer 17

Cleaves PIP2 to form IP3

Question 18

When epinephrine binds to B-adrenergic receptors, what is the result?

Answer 18

Smooth muscle relaxation- vasodilation

Question 19

When epinephrine or norepinephrine binds to a-adrenergic receptors, what is the result?

Answer 19

Smooth muscle contraction- vasoconstriction

Question 20

B-adrenergic receptor pathway uses which primary effector?

Answer 20

Adenylyl cyclase

Question 21

a-adrenergic receptor pathway uses which primary effector?

Answer 21

Phospholipase C

Question 22

What two pathway affects does insulin have?

Answer 22

Growth factor

Metabolic

Question 23

What two metabolic affects does insulin have on a cell?

Answer 23

Opening of more glucose channels and accelerates production of glycogen from glucose

Question 24

What do toll-like receptors do?

Answer 24

Recognize extra cellular components to generate a cell signal

Question 25

What are the 6 requirement for effective signal transduction?

Answer 25

1-Specificity 
2-amplification
3-modularity
4-integration
5-feedback
6-fidelity