title: S-nitrosation of proteins relevant to Alzheimer's disease during early stages of neurodegeneration.
abstract: Protein S-nitrosation (SNO-protein), the nitric oxide-mediated posttranslational modification of cysteine thiols, is an important regulatory mechanism of protein function in both physiological and pathological pathways. A key first step toward elucidating the mechanism by which S-nitrosation modulates a protein's function is identification of the targeted cysteine residues. Here, we present a strategy for the simultaneous identification of SNO-cysteine sites and their cognate proteins to profile the brain of the CK-p25-inducible mouse model of Alzheimer's disease-like neurodegeneration. The approach-SNOTRAP (SNO trapping by triaryl phosphine)-is a direct tagging strategy that uses phosphine-based chemical probes, allowing enrichment of SNO-peptides and their identification by liquid chromatography tandem mass spectrometry. SNOTRAP identified 313 endogenous SNO-sites in 251 proteins in the mouse brain, of which 135 SNO-proteins were detected only during neurodegeneration. S-nitrosation in the brain shows regional differences and becomes elevated during early stages of neurodegeneration in the CK-p25 mouse. The SNO-proteome during early neurodegeneration identified increased S-nitrosation of proteins important for synapse function, metabolism, and Alzheimer's disease pathology. In the latter case, proteins related to amyloid precursor protein processing and secretion are S-nitrosated, correlating with increased amyloid formation. Sequence analysis of SNO-cysteine sites identified potential linear motifs that are altered under pathological conditions. Collectively, SNOTRAP is a direct tagging tool for global elucidation of the SNO-proteome, providing functional insights of endogenous SNO proteins in the brain and its dysregulation during neurodegeneration.
authors.affiliation: Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: Uthpala
authors.initials: U
authors.lastname: Seneviratne
authors.affiliation: The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: Alexi
authors.initials: A
authors.lastname: Nott
authors.affiliation: Agilent Technologies, Inc., Wilmington, DE 19808;
authors.forename: Vadiraja B
authors.initials: VB
authors.lastname: Bhat
authors.affiliation: Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: Kodihalli C
authors.initials: KC
authors.lastname: Ravindra
authors.affiliation: Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: John S
authors.initials: JS
authors.lastname: Wishnok
authors.affiliation: The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139;
authors.forename: Li-Huei
authors.initials: LH
authors.lastname: Tsai
authors.affiliation: Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 srt@mit.edu.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Tannenbaum
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D000595:Amino Acid Sequence; D015538:Nitrosation; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D011506:Proteins
keywords: Alzheimer’s disease; S-nitrosation; neurodegeneration; presenilin pathway; secretase pathway