title: PIASy-dependent SUMOylation regulates DNA topoisomerase IIalpha activity.
abstract: DNA topoisomerase IIα (TopoIIα) is an essential chromosome-associated enzyme with activity implicated in the resolution of tangled DNA at centromeres before anaphase onset. However, the regulatory mechanism of TopoIIα activity is not understood. Here, we show that PIASy-mediated small ubiquitin-like modifier 2/3 (SUMO2/3) modification of TopoIIα strongly inhibits TopoIIα decatenation activity. Using mass spectrometry and biochemical analysis, we demonstrate that TopoIIα is SUMOylated at lysine 660 (Lys660), a residue located in the DNA gate domain, where both DNA cleavage and religation take place. Remarkably, loss of SUMOylation on Lys660 eliminates SUMOylation-dependent inhibition of TopoIIα, which indicates that Lys660 SUMOylation is critical for PIASy-mediated inhibition of TopoIIα activity. Together, our findings provide evidence for the regulation of TopoIIα activity on mitotic chromosomes by SUMOylation. Therefore, we propose a novel mechanism for regulation of centromeric DNA catenation during mitosis by PIASy-mediated SUMOylation of TopoIIα.
authors.affiliation: Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA.
authors.forename: Hyunju
authors.initials: H
authors.lastname: Ryu
authors.forename: Maiko
authors.initials: M
authors.lastname: Furuta
authors.forename: Donald
authors.initials: D
authors.lastname: Kirkpatrick
authors.forename: Steven P
authors.initials: SP
authors.lastname: Gygi
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Azuma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism*; D004250:DNA Topoisomerases, Type II / Q000235:genetics / Q000378:metabolism*; D043864:DNA, Catenated / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism; D050828:Protein Inhibitors of Activated STAT / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D025841:Small Ubiquitin-Related Modifier Proteins / Q000235:genetics / Q000378:metabolism; D058207:Sumoylation; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism; D014982:Xenopus laevis
chemical_list: D000951:Antigens, Neoplasm; D043864:DNA, Catenated; D004268:DNA-Binding Proteins; D018832:Molecular Chaperones; D028861:Nuclear Pore Complex Proteins; D050828:Protein Inhibitors of Activated STAT; D011993:Recombinant Fusion Proteins; D025841:Small Ubiquitin-Related Modifier Proteins; D029867:Xenopus Proteins; C094493:ran-binding protein 2; D004250:DNA Topoisomerases, Type II