Determinants of SUMO1 specificity, E3 ligase and SUMO-RanGAP1 binding activities of the nucleoporin RanBP2*
نویسندگان
چکیده
Background: The RanBP2 internal repeat domain (IR1-M-IR2) catalyzes SUMO E3 ligase activity and binds SUMO1-RanGAP1/UBC9 at the nuclear pore complex. Results: Biochemistry and structures of RanBP2/SUMO-RanGAP1/UBC9 are presented. Conclusion: IR1 protects RanGAP1SUMO1/UBC9 and functions as the primary E3 ligase of RanBP2, while IR2 interacts with SUMO1 to promote weaker SUMO1-specific E3 ligase activity. Significance: RanBP2/SUMO interactions provide insight to SUMO isoform specificity.
منابع مشابه
Determinants of Small Ubiquitin-like Modifier 1 (SUMO1) Protein Specificity, E3 Ligase, and SUMO-RanGAP1 Binding Activities of Nucleoporin RanBP2*
The RanBP2 nucleoporin contains an internal repeat domain (IR1-M-IR2) that catalyzes E3 ligase activity and forms a stable complex with SUMO-modified RanGAP1 and UBC9 at the nuclear pore complex. RanBP2 exhibits specificity for SUMO1 as RanGAP1-SUMO1/UBC9 forms a more stable complex with RanBP2 compared with RanGAP1-SUMO2 that results in greater protection of RanGAP-SUMO1 from proteases. The IR...
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