Synergistic Ca2+ and Cu2+ requirements of the FGF1-S100A13 interaction measured by quartz crystal microbalance:: An initial step in amlexanox-reversible non-classical release of FGF1
Synergistic Ca2+ and Cu2+ requirements of the FGF1-S100A13 interaction measured by quartz crystal microbalance:: An initial step in amlexanox-reversible non-classical release of FGF1
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DOI：
10.1016/j.neuint.2007.11.002
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发表时间：
2008-05-01
影响因子：
4.2
通讯作者：
Ueda, Hiroshi
中科院分区：
文献类型：
--
作者：
Matsunaga, Hayato;Ueda, Hiroshi
已知缺乏常规信号肽序列的成纤维细胞生长因子-1（FGF 1）显示不依赖于内质网-高尔基体系统的非经典释放。最近的研究表明，FGF 1与S100 A13共同释放，S100 A13是一种Ca 2+结合蛋白，作为细胞外货物分子。虽然FGFI和S100 A13都是Cu 2+结合蛋白，但Cu 2+和Ca 2+在非经典释放中的作用仍有待澄清。在本研究中，我们研究了这两种金属离子对这两种蛋白质之间相互作用的要求。Ca ~（2+）的加入显著增加了Strep-tagII-S100 A13与GST-FGF 1相互作用的k（a）值，同时降低了K-D值;这两个值都是通过使用石英晶体微天平（一种实时质量测量装置）获得的。Ca ~（2+）增强相互作用的EC_（50）为10.11 μ M。虽然单独添加Cu 2+没有影响，但它引起了Ca 2+增强相互作用的显着增强。Cu 2+的增强作用的EC 50为50.45 nM。另一方面，通过加入200 nM Cu 2+，Ca 2+的EC 50和K-D值分别从11.69降至2.07 μ M和0.75降至0.38 × 10（-7）M。氨来占诺可抑制FGFI的非经典释放，从而消除Cu 2+诱导的这种相互作用的增强。所有这些发现表明，Ca 2+和Cu 2+的协同作用在FGF 1和S100 A13之间的相互作用中起关键作用，这是FGF 1非经典释放的起始步骤。(C)2007爱思唯尔有限公司版权所有。
it is known that fibroblast growth factor-1 (FGF1) lacking a conventional signal peptide sequence shows non-classical release independent of the endoplasmic reticulum-Golgi system. Recent studies reveal that FGF1 is co-released with S100A13, a Ca2+-binding protein that acts as an extracellular cargo molecule. Although both FGFI and S100A13 are Cu2+-binding proteins, the role of Cu2+, as well as that of Ca2+ in nonclassical release, remains to be clarified. In the present study we examined the requirements of both metal ions for the interaction between these two proteins. The addition of Ca2+ significantly increased the k(a) value, while decreasing the K-D value, for the interaction between Strep-tagII-S100A13 and GST-FGF1; both values were obtained by use of a quartz crystal microbalance, a real-time mass-measuring device. The EC50 of Ca2+ to enhance the interaction was 10.11 mu M. Although the addition of Cu2+ alone had no effect, it caused a marked potentiation of the Ca2+-enhanced interaction. The EC50 Of Cu2+ for the potentiation was 50.45 nM. On the other hand, the EC50 of Ca2+ and the K-D values were decreased from 11.69 to 2.07 mu M and 0.75 to 0.38 x 10(-7) M, respectively, by the addition of 200 nM Cu2+. The Cu2+-induced potentiation of this interaction was abolished by amlexanox, which inhibits non-classical release of FGFI. All of these findings suggest that synergistic effects of Ca2+ and Cu2+ play a key role in the interaction between FGFI and S100A13, which is the initial step in non-classical release of FGF1. (C) 2007 Elsevier Ltd. All rights reserved.