crystal structure of uba2ufd-ubc9 insights into e1-e2 interactions in sumo pathways晶体结构相扑uba2ufd-ubc9洞察e1-e2互动的途径.pdf

Crystal Structure of UBA2ufd-Ubc9: Insights into E1-E2 Interactions in Sumo Pathways 1. 1,2. 1 1 1 Jing Wang , Asad M. Taherbhoy , Harold W. Hunt , Steven N. Seyedin , David W. Miller , Darcie J. Miller1, Danny T. Huang1¤, Brenda A. Schulman1,2,3* 1 Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America, 2 Integrated Program in Biomedical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America, 3 Howard Hughes Medical Institute, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America Abstract Canonical ubiquitin-like proteins (UBLs) such as ubiquitin, Sumo, NEDD8, and ISG15 are ligated to targets by E1-E2-E3 multienzyme cascades. The Sumo cascade, conserved among all eukaryotes, regulates numerous biological processes including protein localization, transcription, DNA replication, and mitosis. Sumo conjugation is initiated by the heterodimeric Aos1-Uba2 E1 enzyme (in humans called Sae1-Uba2), which activates Sumo’s C-terminus, binds the dedicated E2 enzyme Ubc9, and promotes Sumo C-terminal transfer between the Uba2 and Ubc9 catalytic cysteines. To gain insights into details of E1-E2 interactions in the Sumo pathway, we determined crystal structures of the C-terminal ubiquitin fold domain (ufd) from yeast Uba2 (Uba2ufd), alone and in complex with Ubc9. The overall structures of both yeast Uba2ufd and Ubc9 superimpose well on their individual human counterparts