Rolling Blackout is Required for Synaptic Vesicle Exocytosis

1
Rolling Blackout is Required for Synaptic Vesicle
Exocytosis

• Huang, Woodruff, Mohrmann, Broadie

2
Overview

• Rolling Blackout (rbo) is a transmembrane lipase
  for signaling in Drosophila neurons.
• Rbo is essential for neurotransmitter release
  downstream of synaptic vesicle docking.

3
Rbo is Required for Synaptic Transmission

• Rbo mutants move at 22 C and paralyzed at 37 C
• Rbo is localized to presynaptic neurons
• Paralysis is associated temporally with failure
  of synaptic transmission

4
Rbo is Required for Exocytosis After Docking

• White arrowheads docked vesicle
• Black arrowheads active zone
• Increase in amount of docked vesicles

5
Rbo Interacts with Syntaxin downstream of SNARE
complex

• Synergistic interaction between rbo and syx
  mutants
• Same amount of SNARE complex in syx and rbo/syx
  mutants

6
Conclusion

• Rbo mutants cause paralysis, a block of synaptic
  transmission, and docked synaptic vessel
  accumulation at the same time
• Rbo interacts with syntaxin downstream of SNARE
  complex assembly
• So, rbo is part of the machinery necessary for
  synaptic vesicle priming or fusion
• Rbo produces a required lipid or eliminates a
  lipid that negatively regulates fusion