ARHGAP12 Functions as a Developmental Brake on Excitatory Synapse Function

Cell Rep. 2016 Feb 16;14(6):1355-1368. doi: 10.1016/j.celrep.2016.01.037. Epub 2016 Feb 4.

Abstract

The molecular mechanisms that promote excitatory synapse development have been extensively studied. However, the molecular events preventing precocious excitatory synapse development so that synapses form at the correct time and place are less well understood. Here, we report the functional characterization of ARHGAP12, a previously uncharacterized Rho GTPase-activating protein (RhoGAP) in the brain. ARHGAP12 is specifically expressed in the CA1 region of the hippocampus, where it localizes to the postsynaptic compartment of excitatory synapses. ARHGAP12 negatively controls spine size via its RhoGAP activity and promotes, by interacting with CIP4, postsynaptic AMPA receptor endocytosis. Arhgap12 knockdown results in precocious maturation of excitatory synapses, as indicated by a reduction in the proportion of silent synapses. Collectively, our data show that ARHGAP12 is a synaptic RhoGAP that regulates excitatory synaptic structure and function during development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • CA1 Region, Hippocampal / cytology
  • CA1 Region, Hippocampal / metabolism
  • Dendritic Spines / physiology
  • Dendritic Spines / ultrastructure
  • Embryo, Mammalian
  • Endocytosis
  • GTPase-Activating Proteins / genetics*
  • GTPase-Activating Proteins / metabolism
  • Gene Expression Regulation, Developmental*
  • Microtubule-Associated Proteins / genetics*
  • Microtubule-Associated Proteins / metabolism
  • Minor Histocompatibility Antigens / genetics*
  • Minor Histocompatibility Antigens / metabolism
  • Patch-Clamp Techniques
  • Primary Cell Culture
  • Pyramidal Cells / cytology
  • Pyramidal Cells / metabolism*
  • Rats
  • Rats, Wistar
  • Receptors, AMPA / genetics*
  • Receptors, AMPA / metabolism
  • Single-Cell Analysis
  • Synapses / physiology*
  • Synapses / ultrastructure
  • Synaptic Transmission
  • Tissue Culture Techniques

Substances

  • GTPase-Activating Proteins
  • Microtubule-Associated Proteins
  • Minor Histocompatibility Antigens
  • Receptors, AMPA
  • Trip10 protein, rat