Stromalin Constrains Memory Acquisition by Developmentally Limiting Synaptic Vesicle Pool Size

Neuron. 2019 Jan 2;101(1):103-118.e5. doi: 10.1016/j.neuron.2018.11.003. Epub 2018 Nov 28.

Abstract

Stromalin, a cohesin complex protein, was recently identified as a novel memory suppressor gene, but its mechanism remained unknown. Here, we show that Stromalin functions as a negative regulator of synaptic vesicle (SV) pool size in Drosophila neurons. Stromalin knockdown in dopamine neurons during a critical developmental period enhances learning and increases SV pool size without altering the number of dopamine neurons, their axons, or synapses. The developmental effect of Stromalin knockdown persists into adulthood, leading to strengthened synaptic connections and enhanced olfactory memory acquisition in adult flies. Correcting the SV content in dopamine neuron axon terminals by impairing anterograde SV trafficking motor protein Unc104/KIF1A rescues the enhanced-learning phenotype in Stromalin knockdown flies. Our results identify a new mechanism for memory suppression and reveal that the size of the SV pool is controlled genetically and independent from other aspects of neuron structure and function through Stromalin.

Keywords: KIF1A; cohesin; dopamine; olfactory learning; synaptic vesicles.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Animals, Genetically Modified
  • Dopaminergic Neurons / metabolism
  • Dopaminergic Neurons / ultrastructure
  • Drosophila Proteins / deficiency*
  • Drosophila Proteins / genetics
  • Drosophila melanogaster
  • Female
  • Memory / physiology*
  • Nuclear Proteins / deficiency*
  • Nuclear Proteins / genetics
  • Synapses / genetics
  • Synapses / metabolism
  • Synapses / ultrastructure
  • Synaptic Vesicles / genetics
  • Synaptic Vesicles / metabolism*
  • Synaptic Vesicles / ultrastructure*

Substances

  • Drosophila Proteins
  • Nuclear Proteins
  • SA protein, Drosophila