title: Global analysis of S-nitrosylation sites in the wild type (APP) transgenic mouse brain-clues for synaptic pathology.
abstract: Alzheimer's disease (AD) is characterized by an early synaptic loss, which strongly correlates with the severity of dementia. The pathogenesis and causes of characteristic AD symptoms are not fully understood. Defects in various cellular cascades were suggested, including the imbalance in production of reactive oxygen and nitrogen species. Alterations in S-nitrosylation of several proteins were previously demonstrated in various AD animal models and patients. In this work, using combined biotin-switch affinity/nano-LC-MS/MS and bioinformatic approaches we profiled endogenous S-nitrosylation of brain synaptosomal proteins from wild type and transgenic mice overexpressing mutated human Amyloid Precursor Protein (hAPP). Our data suggest involvement of S-nitrosylation in the regulation of 138 synaptic proteins, including MAGUK, CamkII, or synaptotagmins. Thirty-eight proteins were differentially S-nitrosylated in hAPP mice only. Ninety-five S-nitrosylated peptides were identified for the first time (40% of total, including 33 peptides exclusively in hAPP synaptosomes). We verified differential S-nitrosylation of 10 (26% of all identified) synaptosomal proteins from hAPP mice, by Western blotting with specific antibodies. Functional enrichment analysis linked S-nitrosylated proteins to various cellular pathways, including: glycolysis, gluconeogenesis, calcium homeostasis, ion, and vesicle transport, suggesting a basic role of this post-translational modification in the regulation of synapses. The linkage of SNO-proteins to axonal guidance and other processes related to APP metabolism exclusively in the hAPP brain, implicates S-nitrosylation in the pathogenesis of Alzheimer's disease.
authors.affiliation: From the ‡Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland;
authors.forename: Monika
authors.initials: M
authors.lastname: Zaręba-Kozioł
authors.affiliation: §Institute for Molecular Medicine Finland (FIMM), Helsinki, Finland;
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Szwajda
authors.affiliation: From the ‡Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland;
authors.forename: Michał
authors.initials: M
authors.lastname: Dadlez
authors.affiliation: From the ‡Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland; maciej.lalowski@helsinki.fi olawyslouch@ibb.waw.pl.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Wysłouch-Cieszyńska
authors.affiliation: ¶Biomedicum Helsinki, Institute of Biomedicine, Biochemistry/Developmental Biology, Meilahti Clinical Proteomics Core Unit, University of Helsinki, Finland; ‖Folkhälsan Institute of Genetics, Helsinki, Finland maciej.lalowski@helsinki.fi olawyslouch@ibb.waw.pl.
authors.forename: Maciej
authors.initials: M
authors.lastname: Lalowski
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D005260:Female; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D026403:S-Nitrosothiols / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism*; D013574:Synaptosomes
chemical_list: D009419:Nerve Tissue Proteins; D026403:S-Nitrosothiols; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; C496321:Nos1 protein, mouse; C496317:Nos2 protein, mouse