title: SUMOylation of Psmd1 controls Adrm1 interaction with the proteasome.
abstract: SUMOylation is the covalent conjugation of SUMO polypeptides to cellular target proteins. Psmd1 is a subunit of the proteasomal 19S regulatory particle that acts as a docking site for Adrm1, another proteasome subunit that recruits ubiquitinated substrates for proteolysis. Here, we show that the SUMO deconjugating enzyme xSENP1 specifically interacts with Psmd1 and that disruption of xSENP1 targeting delays mitotic exit. Psmd1 becomes SUMOylated through the action of the SUMO E3 enzyme PIASy. We mapped SUMOylation sites within Psmd1 and found that SUMOylation of a critical lysine immediately adjacent to the Adrm1-binding domain regulates the association of Adrm1 with Psmd1. Together, our findings suggest that the interaction of Psmd1 with Adrm1 is controlled by SUMOylation in a manner that may alter proteasome composition and function. These findings demonstrate a mechanism for regulation of ubiquitin-mediated protein degradation by ubiquitin-like proteins of the SUMO family.
authors.affiliation: National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Hyunju
authors.initials: H
authors.lastname: Ryu
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Gygi
authors.affiliation: Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Azuma
authors.affiliation: National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Alexei
authors.initials: A
authors.lastname: Arnaoutov
authors.affiliation: National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address: dassom@mail.nih.gov.
authors.forename: Mary
authors.initials: M
authors.lastname: Dasso
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D058207:Sumoylation
chemical_list: C500781:ADRM1 protein, human; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; C484162:PSMD1 protein, human; D046988:Proteasome Endopeptidase Complex