Structural basis for the regulation of inducible nitric oxide synthase by the SPRY domain-containing SOCS box protein SPSB2, an E3 ubiquitin ligase
Autor: | Huan Wei, Tingting You, Xueyan Guan, Zhihe Kuang, Panqi Zhao, Yuhui Wang, Danting Zhang, Jinjin Yang, Kefa Li, Yanhong Luo |
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Rok vydání: | 2020 |
Předmět: |
0301 basic medicine
Models Molecular Cancer Research Physiology Clinical Biochemistry Nitric Oxide Synthase Type II Peptide Suppressor of Cytokine Signaling Proteins 030204 cardiovascular system & hematology B30.2-SPRY Domain Crystallography X-Ray Nitric Oxide Biochemistry Nitric oxide 03 medical and health sciences chemistry.chemical_compound Mice 0302 clinical medicine Animals Humans Binding site Reactive nitrogen species chemistry.chemical_classification Innate immune system biology Macrophages Proteolysis targeting chimera Ubiquitin ligase Cell biology Nitric oxide synthase DNA-Binding Proteins 030104 developmental biology RAW 264.7 Cells chemistry biology.protein Peptides |
Zdroj: | Nitric oxide : biology and chemistry. |
ISSN: | 1089-8611 |
Popis: | Relatively high concentration of nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) in response to a variety of stimuli is a source of reactive nitrogen species, an important weapon of host innate immune defense. The SPRY domain-containing SOCS box protein 2 (SPSB2) is an E3 ubiquitin ligase that regulates the lifetime of iNOS. SPSB2 interacts with the N-terminal region of iNOS via a binding site on the SPRY domain of SPSB2, and recruits an E3 ubiquitin ligase complex to polyubiquitinate iNOS, leading to its proteasomal degradation. Although critical residues for the SPSB2-iNOS interaction have been identified, structural basis for the interaction remains to be explicitly determined. In this study, we have determined a crystal structure of the N-terminal region of iNOS in complex with the SPRY domain of SPSB2 at 1.24 A resolution. We have resolved the roles of some flanking residues, whose contribution to the SPSB2-iNOS interaction was structurally unclear previously. Furthermore, we have evaluated the effects of SPSB2 inhibitors on NO production using transient transfection and cell-penetrating peptide approaches, and found that such inhibitors can elevate NO production in RAW264.7 macrophages. These results thus provide a useful basis for the development of potent SPSB2 inhibitors as well as recruiting ligands for proteolysis targeting chimera (PROTAC) design. |
Databáze: | OpenAIRE |
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