From the Department of Life Sciences, the Research Center for Cellular Homeostasis, Ewha Womans University, Seoul, 120-750, Republic of Korea.
Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Republic of Korea.
Sci Rep. 2019 Jul 23;9(1):10625. doi: 10.1038/s41598-019-47140-5.
Although syndecan-2 is known to interact with the matrix metalloproteinase-7 (MMP-7), the details of their interaction were unknown. Our experiments with a series of syndecan-2 extracellular domain deletion mutants show that the interaction is mediated through an interaction of the extracellular domain of syndecan-2 (residues 41 to 60) with the α2 helix-loop-α3 helix in the pro-domain of MMP-7. NMR and molecular docking model show that Glu7 of the α1 helix, Glu32 of the α2 helix, and Gly48 and Ser52 of the α2 helix-loop-α3 helix of the MMP-7 pro-domain form the syndecan-2-binding pocket, which is occupied by the side chain of tyrosine residue 51 (Tyr51) of syndecan-2. Consistent with this notion, the expression of a syndecan-2 mutant in which Tyr51 was changed to Ala diminished the interaction between the syndecan-2 extracellular domain and the pro-domain of MMP-7. Furthermore, HT-29 colon adenocarcinoma cells expressing the interaction-defective mutant exhibited reductions in the cell-surface localization of MMP-7, the processing of pro-MMP-7 into active MMP-7, the MMP-7-mediated extracellular domain shedding of both syndecan-2 and E-cadherin, and syndecan-2-mediated anchorage-independent growth. Collectively, these data strongly suggest that Tyr51 of the syndecan-2 extracellular domain mediates its interaction with and activating processing of pro-MMP-7 and regulates MMP-7-dependent syndecan-2 functions.
尽管已知 syndecan-2 与基质金属蛋白酶-7（MMP-7）相互作用，但它们相互作用的细节尚不清楚。我们通过一系列 syndecan-2 细胞外结构域缺失突变体的实验表明，这种相互作用是通过 syndecan-2 的细胞外结构域（残基 41 至 60）与 MMP-7 前肽域的α2 螺旋环-α3 螺旋之间的相互作用介导的。NMR 和分子对接模型表明，MMP-7 前肽域的α1 螺旋中的 Glu7、α2 螺旋中的 Glu32 以及α2 螺旋环-α3 螺旋中的 Gly48 和 Ser52 形成了 syndecan-2 结合口袋，该口袋被 syndecan-2 酪氨酸残基 51（Tyr51）的侧链占据。与这一观点一致的是，将 syndecan-2 中的 Tyr51 突变为 Ala 的突变体的表达减弱了 syndecan-2 细胞外结构域与 MMP-7 前肽域之间的相互作用。此外，表达相互作用缺陷突变体的 HT-29 结肠腺癌细胞中，MMP-7 的细胞表面定位、pro-MMP-7 加工为活性 MMP-7、MMP-7 介导的 syndecan-2 和 E-钙黏蛋白的细胞外结构域脱落以及 syndecan-2 介导的非锚定依赖性生长均减少。总的来说，这些数据强烈表明 syndecan-2 细胞外结构域的 Tyr51 介导了它与 pro-MMP-7 的相互作用及其激活加工，并调节 MMP-7 依赖性 syndecan-2 功能。
