The SUMO1-E67 Interacting Loop Peptide Is an Allosteric Inhibitor of the Dipeptidyl Peptidases 8 and 9*
The SUMO1-E67 Interacting Loop Peptide Is an Allosteric Inhibitor of the Dipeptidyl Peptidases 8 and 9*
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DOI：
10.1074/jbc.m113.489179
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发表时间：
2013-09
期刊：
影响因子：
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通讯作者：
Esther Pilla;Markus Kilisch;C. Lenz;H. Urlaub;Ruth Geiss-Friedlander
中科院分区：
文献类型：
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作者：
Esther Pilla;Markus Kilisch;C. Lenz;H. Urlaub;Ruth Geiss-Friedlander
背景：SUMO1与Pro-肽酶DPP9中的一个臂基序结合，导致该酶的变构激活。结果：覆盖在DPP9相互作用表面的SUMO1多肽可抑制DPP9活性。抑制作用取决于DPP9臂基序中的残基。结论：SUMO1多肽及其变构体是变构DPP9抑制剂。意义：这项工作强调了模拟相互作用表面的多肽用于调节酶活性的潜在用途。细胞内肽酶DPP8和DPP9参与多种细胞途径，包括抗原成熟、细胞内稳态、能量代谢和细胞活力。此前，我们证明了小泛素样蛋白修饰物SUMO1与DPP9中的臂状结构相互作用，导致肽酶的变构激活。在这里，我们证明了E67相互作用环(EIL)肽，对应于SUMO1与DPP9的相互作用面，作为DPP9的非竞争性抑制物。此外，通过分析DPP9手臂突变体对eIL肽的敏感性，我们定位了手臂上对eIL抑制至关重要的特定残基，表明该肽作为DPP9的变构抑制剂发挥作用。通过对EIL多肽的修饰，我们构建了对DPP8(147 Nm)和DPP9(170 Nm)的选择性高于DPPIV(200μm)1000多倍的多肽变体。此外，将这些多肽应用于细胞，可明显抑制细胞内的脯氨酸肽酶活性。重要的是，与以前的文献一致，用这些新的变构多肽抑制剂抑制DPP9会导致EGF介导的Akt磷酸化增加。这项工作强调了模拟相互作用表面的多肽用于调节酶活性的潜在用途。
Background: SUMO1 binds to an arm motif in the prolyl-peptidase DPP9, leading to allosteric activation of the peptidase. Results: A SUMO1 peptide covering the DPP9 interaction surface inhibits DPP9 activity. Inhibition is dependent on residues in the DPP9 arm motif. Conclusion: The SUMO1 peptide and its variants are allosteric DPP9 inhibitors. Significance: This work highlights the potential use of peptides mimicking interaction surfaces for modulating enzyme activity. The intracellular peptidases dipeptidyl peptidase (DPP) 8 and DPP9 are involved in multiple cellular pathways including antigen maturation, cellular homeostasis, energy metabolism, and cell viability. Previously we showed that the small ubiquitin-like protein modifier SUMO1 interacts with an armlike structure in DPP9, leading to allosteric activation of the peptidase. Here we demonstrate that the E67-interacting loop (EIL) peptide, which corresponds to the interaction surface of SUMO1 with DPP9, acts as a noncompetitive inhibitor of DPP9. Moreover, by analyzing the sensitivity of DPP9 arm mutants to the EIL peptide, we mapped specific residues in the arm that are important for inhibition by the EIL, suggesting that the peptide acts as an allosteric inhibitor of DPP9. By modifying the EIL peptide, we constructed peptide variants with more than a 1,000-fold selectivity toward DPP8 (147 nm) and DPP9 (170 nm) over DPPIV (200 μm). Furthermore, application of these peptides to cells leads to a clear inhibition of cellular prolyl peptidase activity. Importantly, in line with previous publications, inhibition of DPP9 with these novel allosteric peptide inhibitors leads to an increase in EGF-mediated phosphorylation of Akt. This work highlights the potential use of peptides that mimic interaction surfaces for modulating enzyme activity.