title: Caspase recruitment domain of procaspase-2 could be a target for SUMO-1 modification through Ubc9.
abstract: To identify the binding proteins that regulate the function of procaspase-2, we screened for proteins using the yeast two-hybrid method and isolated human Ubc9 and SUMO-1 as the candidates. Ubc9 and SUMO-1 interacted with the caspase recruitment domain of procaspase-2 in its N-terminal. We elucidated the covalent modification of procaspase-2 by SUMO-1 in mammalian cells by immunoprecipitation followed by Western blot analysis. Procaspase-2 and SUMO-1 were co-localized by dot-like structures in the nucleus that are related to promyelocytic leukemia bodies. Interestingly, a conjugation-deficient mutant (K60R) procaspase-2 resulted in a delay of its enzyme maturation (appearance of p12 subunit) compared to that of wild-type. Thus, the modification with SUMO-1 may play a critical role in the nuclear localization and the activation (maturation) of procaspase-2.
authors.affiliation: Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Shirakura
authors.forename: Naoko
authors.initials: N
authors.lastname: Hayashi
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Ogino
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tsuruma
authors.forename: Takashi
authors.initials: T
authors.lastname: Uehara
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Nomura
mesh_terms: D015153:Blotting, Western; D053143:Caspase 2; D020169:Caspases / Q000378:metabolism*; D004789:Enzyme Activation; D025842:SUMO-1 Protein / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism*; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: D025842:SUMO-1 Protein; D044763:Ubiquitin-Conjugating Enzymes; D053143:Caspase 2; D020169:Caspases; D000098843:Ubiquitin-Conjugating Enzyme UBC9