title: SUMO-1 conjugation in vivo requires both a consensus modification motif and nuclear targeting.
abstract: SUMO-1 is a small ubiquitin-related modifier that is covalently linked to many cellular protein targets. Proteins modified by SUMO-1 and the SUMO-1-activating and -conjugating enzymes are located predominantly in the nucleus. Here we define a transferable sequence containing the PsiKXE motif, where Psi represents a large hydrophobic amino acid, that confers the ability to be SUMO-1-modified on proteins to which it is linked. Whereas addition of short sequences from p53 and IkappaBalpha, containing the PsiKXE motif, to a carrier protein is sufficient for modification in vitro, modification in vivo requires the additional presence of a nuclear localization signal. Thus, protein substrates must be targeted to the nucleus to undergo SUMO-1 conjugation.
authors: School of Biology, Biomolecular Sciences Building, University of St. Andrews, St. Andrews, Fife KY169ST, United Kingdom.
authors: M S
authors: MS
authors: Rodriguez
authors: C
authors: C
authors: Dargemont
authors: R T
authors: RT
authors: Hay
mesh_terms: D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism*; D016384:Consensus Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D020690:GTPase-Activating Proteins / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D020672:I-kappa B Proteins; D000072000:NF-KappaB Inhibitor alpha; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D025842:SUMO-1 Protein; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000378:metabolism*; D014452:Ubiquitins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D020690:GTPase-Activating Proteins; D020672:I-kappa B Proteins; C000606204:NFKBIA protein, human; C092317:RANGAP1 protein, human; D011993:Recombinant Fusion Proteins; D025842:SUMO-1 Protein; D016159:Tumor Suppressor Protein p53; D014452:Ubiquitins; D000072000:NF-KappaB Inhibitor alpha