title: Single-synapse analysis of a diverse synapse population: proteomic imaging methods and markers.
abstract: A lack of methods for measuring the protein compositions of individual synapses in situ has so far hindered the exploration and exploitation of synapse molecular diversity. Here, we describe the use of array tomography, a new high-resolution proteomic imaging method, to determine the composition of glutamate and GABA synapses in somatosensory cortex of Line-H-YFP Thy-1 transgenic mice. We find that virtually all synapses are recognized by antibodies to the presynaptic phosphoprotein synapsin I, while antibodies to 16 other synaptic proteins discriminate among 4 subtypes of glutamatergic synapses and GABAergic synapses. Cell-specific YFP expression in the YFP-H mouse line allows synapses to be assigned to specific presynaptic and postsynaptic partners and reveals that a subpopulation of spines on layer 5 pyramidal cells receives both VGluT1-subtype glutamatergic and GABAergic synaptic inputs. These results establish a means for the high-throughput acquisition of proteomic data from individual cortical synapses in situ.
authors.affiliation: Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA. kmicheva@stanford.edu
authors.forename: Kristina D
authors.initials: KD
authors.lastname: Micheva
authors.forename: Brad
authors.initials: B
authors.lastname: Busse
authors.forename: Nicholas C
authors.initials: NC
authors.lastname: Weiler
authors.forename: Nancy
authors.initials: N
authors.lastname: O'Rourke
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Smith
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence / Q000379:methods / Q000639:trends; D040081:Protein Array Analysis / Q000379:methods; D040901:Proteomics / Q000379:methods* / Q000639:trends; D018079:Receptors, GABA / Q000032:analysis / Q000378:metabolism; D013569:Synapses / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure*; D016704:Synapsins / Q000032:analysis / Q000378:metabolism; D050598:Vesicular Glutamate Transport Protein 1 / Q000032:analysis / Q000378:metabolism; D050599:Vesicular Glutamate Transport Protein 2 / Q000032:analysis / Q000378:metabolism
chemical_list: D015415:Biomarkers; D018079:Receptors, GABA; C493477:Slc17a6 protein, mouse; C493465:Slc17a7 protein, mouse; D016704:Synapsins; D050598:Vesicular Glutamate Transport Protein 1; D050599:Vesicular Glutamate Transport Protein 2