title: In vivo localization and identification of SUMOylated proteins in the brain of His6-HA-SUMO1 knock-in mice.
abstract: SUMOylation, an essential posttranslational protein modification, is involved in many eukaryotic cellular signaling pathways. The identification of SUMOylated proteins is difficult, because SUMOylation sites in proteins are hard to predict, SUMOylated protein states are transient in vivo and labile in vitro, only a small substrate fraction is SUMOylated in vivo, and identification tools for natively SUMOylated proteins are rare. To solve these problems, we generated knock-in mice expressing His(6)-HA-SUMO1. By anti-HA immunostaining, we show that SUMO1 conjugates in neurons are only detectable in nuclei and annulate lamellae. By anti-HA affinity purification, we identified several hundred candidate SUMO1 substrates, of which we validated Smchd1, Ctip2, TIF1γ, and Zbtb20 as novel substrates. The knock-in mouse represents an excellent mammalian model for studies on SUMO1 localization and screens for SUMO1 conjugates in vivo.
authors.affiliation: Department of Molecular Neurobiology,  Max Planck Institute of Experimental Medicine, 37075 Göttingen,  Germany.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Tirard
authors.forename: He-Hsuan
authors.initials: HH
authors.lastname: Hsiao
authors.forename: Miroslav
authors.initials: M
authors.lastname: Nikolov
authors.forename: Henning
authors.initials: H
authors.lastname: Urlaub
authors.forename: Frauke
authors.initials: F
authors.lastname: Melchior
authors.forename: Nils
authors.initials: N
authors.lastname: Brose
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured / Q000166:cytology*; D006624:Hippocampus / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism; D011485:Protein Binding; D025842:SUMO-1 Protein / Q000378:metabolism*; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism*
chemical_list: D025842:SUMO-1 Protein; C515972:SUMO2 protein, mouse; D025841:Small Ubiquitin-Related Modifier Proteins