lecture 3

Question 1

transduction

Answer 1

• cascades of molecular interactions relay signals from receptors to target molecules
• usually multistep process involving many molecules
• binding of signal molecule trigger first step in change molecular interactions

Question 2

signal transduction pathways

Answer 2

• receptor > protein > protein etc. > response producing protein

Question 3

protein phosphorylation and dephosphorylation

Answer 3

• protein kinase = transfer of P grp from ATP to protein (activation)
  – inactive protein kinase + activated relay molecule –> active protein kinase
  – active protein kinase + P (ATP) –> inactive protein kinase + ADP
  – continues…
• inactivation of phosphorylated proteins
  – phosphate group removed by protein phosphatases

Question 4

second messenger

Answer 4

• not all components of signal transduction pathways are proteins
  – cyclic AMP and Ca 2+ ions

Question 5

cAMP diseases

Answer 5

• cholera bacterium
• vibrio cholerea
• produce toxin modifying G protein (stuck in active form)

Question 6

calcium and IP3 signalling pathways

Answer 6

• (add image)