title: Dendritic spine morphology determines membrane-associated protein exchange between dendritic shafts and spine heads.
abstract: The purpose of this study was to examine whether variability in the shape of dendritic spines affects protein movement within the plasma membrane. Using a combination of confocal microscopy and the fluorescence loss in photobleaching technique in living hippocampal CA1 pyramidal neurons expressing membrane-linked GFP, we observed a clear correlation between spine shape parameters and the diffusion and compartmentalization of membrane-associated proteins. The kinetics of membrane-linked GFP exchange between the dendritic shaft and the spine head compartment were slower in dendritic spines with long necks and/or large heads than in those with short necks and/or small heads. Furthermore, when the spine area was reduced by eliciting epileptiform activity, the kinetics of protein exchange between the spine compartments exhibited a concomitant decrease. As synaptic plasticity is considered to involve the dynamic flux by lateral diffusion of membrane-bound proteins into and out of the synapse, our data suggest that spine shape represents an important parameter in the susceptibility of synapses to undergo plastic change.
authors.affiliation: Brain Research Institute, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland. hugel@neurochem.u-strasbg.fr
authors.forename: Sylvain
authors.initials: S
authors.lastname: Hugel
authors.forename: Mathias
authors.initials: M
authors.lastname: Abegg
authors.forename: Vincenzo
authors.initials: V
authors.lastname: de Paola
authors.forename: Pico
authors.initials: P
authors.lastname: Caroni
authors.forename: Beat H
authors.initials: BH
authors.lastname: Gähwiler
authors.forename: R Anne
authors.initials: RA
authors.lastname: McKinney
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D049229:Dendritic Spines / Q000378:metabolism / Q000648:ultrastructure*; D006624:Hippocampus / Q000378:metabolism / Q000648:ultrastructure; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009924:Organ Culture Techniques; D017966:Pyramidal Cells / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D008565:Membrane Proteins