title: Actin capping protein is required for dendritic spine development and synapse formation.
abstract: Dendritic spines serve as the postsynaptic platform for most excitatory synapses in the mammalian brain, and their shape and size are tightly correlated with synaptic strength. The actin cytoskeleton plays a crucial role in the spine structure and its modifications during synapse development and plasticity, but the underlying regulatory mechanisms remain to be elucidated. Here, we report that actin capping protein (CP), a regulator of actin filament growth, plays an essential role for spine development and synapse formation. We found that CP expression in rat hippocampus is elevated at and after the stage of substantial synapse formation. CP knockdown in hippocampal cultures resulted in a marked decline in spine density accompanied by increased filopodia-like protrusions. Moreover, the spines of CP knockdown neurons exhibited an altered morphology, highlighted by multiple thin filopodia-like protrusions emerging from the spine head. Finally, the number of functional synapses was reduced by CP knockdown as evidenced by a reduction in the density of paired presynaptic and postsynaptic markers and in the frequency of miniature EPSCs. These findings indicate that capping of actin filaments by CP represents an essential step for the remodeling of the actin architecture underlying spine morphogenesis and synaptic formation during development.
authors.affiliation: Department of Cell Biology and Neurology, Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Fan
authors.forename: Xin
authors.initials: X
authors.lastname: Tang
authors.forename: Eric
authors.initials: E
authors.lastname: Vitriol
authors.forename: Gong
authors.initials: G
authors.lastname: Chen
authors.forename: James Q
authors.initials: JQ
authors.lastname: Zheng
mesh_terms: D051344:Actin Capping Proteins / Q000378:metabolism*; D000818:Animals; D049229:Dendritic Spines / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011554:Pseudopodia / Q000378:metabolism; D051381:Rats; D013569:Synapses / Q000378:metabolism*
chemical_list: D051344:Actin Capping Proteins