title: Crystal structure of Ufc1, the Ufm1-conjugating enzyme.
abstract: Ubiquitin and ubiquitin-like protein-conjugating enzymes play central roles in posttranslational modification processes. The ubiquitin-fold modifier 1 (Ufm1), one of a variety of ubiquitin-like modifiers, is covalently attached to target proteins via Uba5 and Ufm1-conjugating enzyme 1 (Ufc1), which are analogous to the E1 and E2 ubiquitylation enzymes. As Ufm1-related proteins are conserved in metazoa and plants, the Ufm1 system likely plays important roles in various multicellular organisms. Herein, we report the X-ray structure of human Ufc1 determined at 1.6 A resolution. The Ufc1 structure comprises a canonical E2 domain and an additional N-terminal domain. The Uba5 binding site on Ufc1 was assigned by structural comparison of Ufc1 and Ubc12 and related mutational analyses. In addition, we show that the N-terminal unique domain of Ufc1 contributes to thermal stability.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan.
authors.forename: Tsunehiro
authors.initials: T
authors.lastname: Mizushima
authors.forename: Kanako
authors.initials: K
authors.lastname: Tatsumi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ozaki
authors.forename: Tatsukuni
authors.initials: T
authors.lastname: Kawakami
authors.forename: Atsuo
authors.initials: A
authors.lastname: Suzuki
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ogasahara
authors.forename: Masaaki
authors.initials: M
authors.lastname: Komatsu
authors.forename: Eiki
authors.initials: E
authors.lastname: Kominami
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamane
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D003198:Computer Simulation; D003461:Crystallography; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D044763:Ubiquitin-Conjugating Enzymes / Q000737:chemistry* / Q000648:ultrastructure*