title: Ubc9 sumoylation controls SUMO chain formation and meiotic synapsis in Saccharomyces cerevisiae.
abstract: Posttranslational modification with the small ubiquitin-related modifier SUMO depends on the sequential activities of E1, E2, and E3 enzymes. While regulation by E3 ligases and SUMO proteases is well understood, current knowledge of E2 regulation is very limited. Here, we describe modification of the budding yeast E2 enzyme Ubc9 by sumoylation (Ubc9(*)SUMO). Although less than 1% of Ubc9 is sumoylated at Lys153 at steady state, a sumoylation-deficient mutant showed significantly reduced meiotic SUMO conjugates and abrogates synaptonemal complex formation. Biochemical analysis revealed that Ubc9(*)SUMO is severely impaired in its classical activity but promoted SUMO chain assembly in the presence of Ubc9. Ubc9(*)SUMO cooperates with charged Ubc9 (Ubc9~SUMO) by noncovalent backside SUMO binding and by positioning the donor SUMO for optimal transfer. Thus, sumoylation of Ubc9 converts an active enzyme into a cofactor and reveals a mechanism for E2 regulation that orchestrates catalytic (Ubc9~SUMO) and noncatalytic (Ubc9(*)SUMO) functions of Ubc9.
authors: Department of Epigenetics, Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108 Freiburg, Germany.
authors: Helene
authors: H
authors: Klug
authors: Martin
authors: M
authors: Xaver
authors: Viduth K
authors: VK
authors: Chaugule
authors: Stefanie
authors: S
authors: Koidl
authors: Gerhard
authors: G
authors: Mittler
authors: Franz
authors: F
authors: Klein
authors: Andrea
authors: A
authors: Pichler
mesh_terms: D008239:Lysine / Q000378:metabolism; D008540:Meiosis; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D058207:Sumoylation; D013573:Synaptonemal Complex / Q000378:metabolism; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics / Q000378:metabolism*; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: D044763:Ubiquitin-Conjugating Enzymes; D000098843:Ubiquitin-Conjugating Enzyme UBC9; D008239:Lysine