Lecture 5 - 14-3-3 Binding Phosphoproteome

Question 1

14-3-3 Dimer:

Answer 1

• Multiple Isoforms (Homo- and Hetero-dimers)
• Present in every eukaryotic cell
• Dock onto specific phosphorylated motifs (14-3-3 dimers dock onto 2 tandem phosphates)
• 14-3-3 binding to phosphoprotein targets is a common mechanism for linking signalling pathways to the regulation of cellular metabolism, growth, proliferation, and movement.

Question 2

Docking of a phosphosite in a linker region of MAP3K5 into the central groove of 14-3-3 pulls the kinase domain against the back end of 14-3-3, which inhibits the enzyme by steric hindrance.
TRUE OR FALSE

Answer 2

TRUE

Question 3

Insulin regulates binding to 100s of phosphoproteins linked to established and emerging actions of insulin:

Answer 3

Increase

• Glucose Uptake
• Amino Acid Uptake
• K+ and PO4^3- Uptake
• Glycogen Synthesis
• Glycolysis In Heart
• Lipid Synthesis
• Esterification of Fatty Acids

Decrease:

• Lipolysis
• Gluconeogenesis
• Autophagy