title: Small ubiquitin-like modifier 3-modified proteome regulated by brain ischemia in novel small ubiquitin-like modifier transgenic mice: putative protective proteins/pathways.
abstract: OBJECTIVE
  Small ubiquitin-like modifier (SUMO) conjugation is a post-translational modification associated with many human diseases. Characterization of the SUMO-modified proteome is pivotal to define the mechanistic link between SUMO conjugation and such diseases. This is particularly evident for SUMO2/3 conjugation, which is massively activated after brain ischemia/stroke, and is believed to be a protective response. The purpose of this study was to perform a comprehensive analysis of the SUMO3-modified proteome regulated by brain ischemia using a novel SUMO transgenic mouse.
  
  
  METHODS
  To enable SUMO proteomics analysis in vivo, we generated transgenic mice conditionally expressing tagged SUMO1-3 paralogues. Transgenic mice were subjected to 10 minutes forebrain ischemia and 1 hour of reperfusion. SUMO3-conjugated proteins were enriched by anti-FLAG affinity purification and analyzed by liquid chromatography-tandem mass spectrometry.
  
  
  RESULTS
  Characterization of SUMO transgenic mice demonstrated that all 3 tagged SUMO paralogues were functionally active, and expression of exogenous SUMOs did not modify the endogenous SUMOylation machinery. Proteomics analysis identified 112 putative SUMO3 substrates of which 91 candidates were more abundant in the ischemia group than the sham group. Data analysis revealed processes/pathways with putative neuroprotective functions, including glucocorticoid receptor signaling, RNA processing, and SUMOylation-dependent ubiquitin conjugation.
  
  
  CONCLUSIONS
  The identified proteins/pathways modulated by SUMOylation could be the key to understand the mechanisms linking SUMOylation to neuroprotection, and thus provide new promising targets for therapeutic interventions. The new transgenic mouse will be an invaluable platform for analyzing the SUMO-modified proteome in models of human disorders and thereby help to mechanistically link SUMOylation to the pathological processes.
authors.affiliation: From the Department of Anesthesiology (W.Y., H.S., L.W., P.M., X.L., W.P.), Proteomics Core Facility (J.W.T., M.A.M.), and Department of Neurobiology (S.Z.), Duke University Medical Center, Durham, NC; and Department of Neurosurgery, The Fifth Central Hospital of Tianjin, Tianjin, China (X.L.).
authors.forename: Wei
authors.initials: W
authors.lastname: Yang
authors.forename: Huaxin
authors.initials: H
authors.lastname: Sheng
authors.forename: J Will
authors.initials: JW
authors.lastname: Thompson
authors.forename: Shengli
authors.initials: S
authors.lastname: Zhao
authors.forename: Liangli
authors.initials: L
authors.lastname: Wang
authors.forename: Pei
authors.initials: P
authors.lastname: Miao
authors.forename: Xiaozhi
authors.initials: X
authors.lastname: Liu
authors.forename: M Arthur
authors.initials: MA
authors.lastname: Moseley
authors.forename: Wulf
authors.initials: W
authors.lastname: Paschen
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D002546:Ischemic Attack, Transient / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D013058:Mass Spectrometry; D051379:Mice; D008822:Mice, Transgenic; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D012323:RNA Processing, Post-Transcriptional; D025842:SUMO-1 Protein / Q000235:genetics / Q000378:metabolism; D025841:Small Ubiquitin-Related Modifier Proteins / Q000235:genetics / Q000378:metabolism; D020521:Stroke / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D014452:Ubiquitins / Q000235:genetics* / Q000378:metabolism*
chemical_list: D020543:Proteome; D025842:SUMO-1 Protein; C515972:SUMO2 protein, mouse; D025841:Small Ubiquitin-Related Modifier Proteins; C117908:Sumo3 protein, mouse; D014452:Ubiquitins
keywords: SUMO proteins; brain ischemia; proteomics; transgenic mice