Molecular target 3

Question 1

Difference between primary and secondary active transport

Answer 1

Question 2

What are the different transporters

Answer 2

Question 3

Pumps (transporters) can be divided into what four categories

Answer 3

Question 4

Metabolite transporters

Answer 4

• 31 families
• Important drug target e.g. chloroquine

Question 5

How do neurotransmitter transporters work

Answer 5

They transport vesicles containing neurotransmitters
- Vesicular inhibitory AA transporter
- Vesicular excitatory AA transporter
- Vesicular amine transporter
They are mainly used for scientific research

Question 6

Neurotransmitter transporters name examples and where are they found

Answer 6

• They can be found in plasma membrane (presynaptic, postsynaptic and glial localisation)

Question 7

How does citalopram work

Answer 7

• Its a seratonin/5-HT transporter
• Type of neurotransmitter transport (5-HT)

Question 8

How does riluzole work

Answer 8

• EAAT; excitatory amino acid transport

Question 9

Transporters as drugs

Answer 9

Question 10

What an enzyme-coupled receptor

Answer 10

• Type of transmembrane receptor when bound by a ligand (growth factor or hormone) it functions as an enzyme

Question 11

Classifications of ECRs

Answer 11

Receptor tyrosine kinases (main one)
Tyrosine kinase-associated receptors
Receptor serine/threonine kinases
Histidine-kinase-associated receptors
Receptor guanylyl cyclases
Receptor-like tyrosine phosphatases

Question 12

Receptor tyrosine kinases

Answer 12

• Phosphorylate tyrosine residue on a specific set of substrates
• Usually activated by secrete growth factors and hormones

Question 13

How are signals transduced across the plasma membrane? - ECR

Answer 13

1. For GPCRs, ligands induce a conformational change
2. Most ECRs are single a-helicase
3. Receptor subunits create dimers or oligomers
4. Oligomerisation of ECRs cause reorienation
5. Reorientation - signalling- autophosphorylation

Question 14

How does autophosphorylation cause biological effects?

Answer 14

• When a kinase enzyme adds a phosphate to itself
• This alters the enzymes structure and function

Question 15

Why do we need to understand
molecular signalling pathway?

Answer 15

Identification of molecules involved in signalling may unearth new targets for drugs

EGF promotes cellular proliferation

Mutations in the EGF receptor have been identified in cancer

EGF and EGF-activated pathways are targets for anti-cancer therapies
Anti-EGF receptor antibodies
Tyrosine kinase inhibitors

Question 16

Signalling through the insulin receptor

Answer 16

Question 17

How does insulin promote glycogen synthesis?

Answer 17