GPK

Glycogen Phosphorylase

Transferase that turns Glycogen Phosphorylase a into Glycogen Phosphorylase b

Transferases

Glycogen Phosphorylase Kinase

• Important modificaiton and regulatory site

Fundamentals:

• Activated by phosphorylation, INC Calcium
• Maximal activity after activation of both chemicals

Structure:

• alpha-beta-gamma-delta

Specifics:

• alhpa phosphorylation (after beta phosphorylastion) signals termination
  • Protein Phosphorylase 1 dephosphorylates the beta subunit
• beta phosphorylation converts the low activity into a high activity
  • Protein Kinase A (PKA)
• delta subunit - Calmodulin
  • Partially activated by INC Calcium

Concepts:

• Focus on muscles, signal that initiates muscle contraction Calcium also stimulates the release of glucose to fuel the contraction