title: Mass spectrometric analysis of synaptosomal membrane preparations for the determination of brain receptors, transporters and channels.
abstract: The molecular composition of synaptic signal transduction machineries shapes synaptic neurotransmission. The repertoire of receptors, transporters and channels (RTCs) comprises major signaling events in the brain. RTCs are conventionally studied by candidate immunohistochemistry and biochemistry, which are low throughput with resolution greatly affected by available immunoreagents and membrane interference. Therefore, a comprehensive resource of synaptic brain RTCs is still lacking. In particular, studies on the detergent-soluble synaptosomal fraction, known to contain transporters and channels, are limited. We, therefore, performed sub-synaptosomal fractionation of rat cerebral cortex, followed by trypsin/chymotrypsin sequential digestion of a detergent-soluble synaptosomal fraction and a postsynaptic density preparation, stable-isotope tryptic peptide labeling and liquid chromatography mass spectrometry. Based on the current study, a total of 4784 synaptic proteins were submitted to the ProteomExchange database (PXD001948), including 274 receptors, 394 transporters/channels and 1377 transmembrane proteins. Function-based classification assigned 1781 proteins as probable drug targets with 834 directly linked to brain disorders. The analytical approach identified 499 RTCs that are not listed in the largest, curated database for synaptosomal proteins (SynProt). This is a threefold RTC increase over all other data collected to date. Taken together, we present a protein discovery resource that can serve as a benchmark for future molecular interrogation of synaptic connectivity.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria.|CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.
authors.forename: Fernando J
authors.initials: FJ
authors.lastname: Sialana
authors.affiliation: Laboratory of Proteomics, Institute of Biology, Eötvös Loránd University, Budapest, Hungary.
authors.forename: Peter
authors.initials: P
authors.lastname: Gulyassy
authors.affiliation: CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Májek
authors.affiliation: Science for Life Laboratory, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden.|Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.
authors.forename: Evelina
authors.initials: E
authors.lastname: Sjöstedt
authors.affiliation: Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary.
authors.forename: Viktor
authors.initials: V
authors.lastname: Kis
authors.affiliation: CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.
authors.forename: André C
authors.initials: AC
authors.lastname: Müller
authors.affiliation: Institute of Medical Chemistry, Medical University of Vienna, Vienna, Austria.
authors.forename: Elena L
authors.initials: EL
authors.lastname: Rudashevskaya
authors.affiliation: Science for Life Laboratory, Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Jan
authors.initials: J
authors.lastname: Mulder
authors.affiliation: CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.
authors.forename: Keiryn L
authors.initials: KL
authors.lastname: Bennett
authors.affiliation: Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria.
authors.forename: Gert
authors.initials: G
authors.lastname: Lubec
mesh_terms: D000818:Animals; D002458:Cell Fractionation; D002540:Cerebral Cortex / Q000737:chemistry*; D003902:Detergents / Q000737:chemistry; D008297:Male; D026901:Membrane Transport Proteins / Q000032:analysis*; D020543:Proteome / Q000032:analysis; D040901:Proteomics; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility; D013574:Synaptosomes / Q000737:chemistry*; D053719:Tandem Mass Spectrometry
chemical_list: D003902:Detergents; D026901:Membrane Transport Proteins; D020543:Proteome
keywords: Animal proteomics; Channels; Membrane; Receptors; Transporters