title: Structural and functional studies of SIZ1, a PIAS-type SUMO E3 ligase from Arabidopsis.
abstract: Small ubiquitin-like modifier (SUMO) is a post-translational modifier peptide that is involved in several biological processes in eukaryotes. Arabidopsis SIZ1, a SUMO E3 ligase, is an ortholog of the mammalian PIAS (Protein Inhibitor of Activated STAT) and yeast SIZ (SAP/Miz) proteins. SIZ1 contains all of the typical domains of PIAS/SIZ-type proteins, such as the PINIT, SAP, SP-RING, and plant-specific PHD domains. SIZ1 plays a pivotal role in controlling SUMOylation, and disruption of its function has been reported to affect stress responses, growth, and development. We performed a structural and functional analysis of SIZ1 by determining the phenotypes of siz1 knockout mutants transformed with SIZ1 alleles carrying point mutations in predicted SIZ1 domains. This study establishes that the diverse properties characteristic of SIZ1 are associated with specific domains and that they can be separated.
authors.affiliation: Division of Applied Life Science (BK21 program), PMBBRC, EB-NCRC, Gyeongsang National University, Jinju, Korea.
authors.forename: Mi Sun
authors.initials: MS
authors.lastname: Cheong
authors.affiliation: Division of Applied Life Science (BK21 program), PMBBRC, EB-NCRC, Gyeongsang National University, Jinju, Korea.
authors.forename: Hyeong Cheol
authors.initials: HC
authors.lastname: Park
authors.affiliation: Division of Applied Life Science (BK21 program), PMBBRC, EB-NCRC, Gyeongsang National University, Jinju, Korea.
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Bohnert
authors.affiliation: Division of Applied Life Science (BK21 program), PMBBRC, EB-NCRC, Gyeongsang National University, Jinju, Korea.
authors.forename: Ray A
authors.initials: RA
authors.lastname: Bressan
authors.affiliation: Division of Applied Life Science (BK21 program), PMBBRC, EB-NCRC, Gyeongsang National University, Jinju, Korea.
authors.forename: Dae-Jin
authors.initials: DJ
authors.lastname: Yun
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000378:metabolism*; D008025:Ligases / Q000737:chemistry* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D044767:Ubiquitin-Protein Ligases; D008025:Ligases; C502552:SIZ1 protein, Arabidopsis