Backbone dynamics of the 18.5 kDa isoform of myelin basic protein reveals transient alpha-helices and a calmodulin-binding site.
Backbone dynamics of the 18.5 kDa isoform of myelin basic protein reveals transient alpha-helices and a calmodulin-binding site.
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髓磷脂碱性蛋白 18.5 kDa 亚型的主链动力学揭示了短暂的 α 螺旋和钙调蛋白结合位点。
DOI：
10.1529/biophysj.107.125823
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发表时间：
2008
影响因子：
3.4
通讯作者：
G. Harauz
中科院分区：
文献类型：
--
作者：
D. Libich;G. Harauz
髓鞘碱性蛋白（MBP）的18.5kDa同种型是成人中枢神经系统髓鞘中的主要形式。它是一种内在无序的蛋白质，在膜粘附中起作用，并作为连接少突胶质细胞膜与底层细胞骨架的接头;其与钙调蛋白和含SH 3结构域的蛋白质的特异性相互作用表明在信号传导中的进一步多功能性。在这里，我们使用多维异谱核磁共振光谱研究了蛋白质在水溶液（100 mM KCl）和膜模拟溶剂（30% TFE-d（2））中对环境的构象依赖性，特别是使用化学位移索引分析其二级结构，并使用（15）N自旋弛豫测量研究其主链动力学。总的来说，数据揭示了具有α-螺旋倾向的蛋白质的三个主要区段，其通过膜模拟条件稳定：T33-D46、V83-T92和T142-L154（鼠18.5kDa序列编号）。所有这些区域都符合生物信息学预测的有序二级结构。V83-T92区包含一个主要的免疫显性表位，该表位先前已通过定点自旋标记和电子顺磁共振光谱显示在膜重构系统中是α-螺旋的。T142-L154片段与预测的钙调素结合位点重叠。使用标记的MBP和未标记的钙调蛋白的化学位移扰动实验表明，在MBP的两种蛋白质的协会后，一个戏剧性的构象变化，并与MBP的C-末端部分是钙调蛋白的主要结合位点是一致的。
The 18.5 kDa isoform of myelin basic protein (MBP) is the predominant form in adult human central nervous system myelin. It is an intrinsically disordered protein that functions both in membrane adhesion, and as a linker connecting the oligodendrocyte membrane to the underlying cytoskeleton; its specific interactions with calmodulin and SH3-domain containing proteins suggest further multifunctionality in signaling. Here, we have used multidimensional heteronuclear nuclear magnetic resonance spectroscopy to study the conformational dependence on environment of the protein in aqueous solution (100 mM KCl) and in a membrane-mimetic solvent (30% TFE-d(2)), particularly to analyze its secondary structure using chemical shift indexing, and to investigate its backbone dynamics using (15)N spin relaxation measurements. Collectively, the data revealed three major segments of the protein with a propensity toward alpha-helicity that was stabilized by membrane-mimetic conditions: T33-D46, V83-T92, and T142-L154 (murine 18.5 kDa sequence numbering). All of these regions corresponded with bioinformatics predictions of ordered secondary structure. The V83-T92 region comprises a primary immunodominant epitope that had previously been shown by site-directed spin labeling and electron paramagnetic resonance spectroscopy to be alpha-helical in membrane-reconstituted systems. The T142-L154 segment overlapped with a predicted calmodulin-binding site. Chemical shift perturbation experiments using labeled MBP and unlabeled calmodulin demonstrated a dramatic conformational change in MBP upon association of the two proteins, and were consistent with the C-terminal segment of MBP being the primary binding site for calmodulin.
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DOI：
10.1073/pnas.90.22.10695
发表时间：
1993-11-15
影响因子：
11.1
作者：
PRIBYL, TM;CAMPAGNONI, CW;CAMPAGNONI, AT
通讯作者：
CAMPAGNONI, AT
DOI：
--
发表时间：
2004
期刊：
--
影响因子：
--
作者：
Jacob Bruggemann;Gabriel C. Lander;Andrew I. Su
通讯作者：
Jacob Bruggemann;Gabriel C. Lander;Andrew I. Su
DOI：
10.1016/s0021-9258(18)53485-2
发表时间：
1993-03
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
A. Campagnoni;T. Pribyl;C. Campagnoni;K. Kampf;S. Amur‐Umarjee;C. Landry;V. Handley;S. Newman;B. Garbay;K. Kitamura
通讯作者：
A. Campagnoni;T. Pribyl;C. Campagnoni;K. Kampf;S. Amur‐Umarjee;C. Landry;V. Handley;S. Newman;B. Garbay;K. Kitamura
影响因子：
--
作者：
Zhengshuang Shi;R. Woody;N. Kallenbach
通讯作者：
Zhengshuang Shi;R. Woody;N. Kallenbach
影响因子：
15
作者：
Schwarzinger, S;Kroon, GJA;Dyson, HJ
通讯作者：
Dyson, HJ