The myristoylation of guanylate cyclase‐activating protein‐2 causes an increase in thermodynamic stability in the presence but not in the absence of Ca2+
The myristoylation of guanylate cyclase‐activating protein‐2 causes an increase in thermodynamic stability in the presence but not in the absence of Ca2+
复制标题
鸟苷酸环化酶激活蛋白-2 的肉豆蔻酰化会在 Ca2+ 存在但不存在的情况下导致热力学稳定性增加
作者：
T. Schröder;H. Lilie;C. Lange
鸟苷酸环化酶激活蛋白- 2 （GCAP - 2）是神经元钙传感器（NCS）家族的一种Ca2+结合蛋白。无Ca2+ GCAP‐2激活视网膜杆外段鸟苷酸环化酶ROS‐GC1和2。原生GCAP‐2是N端肉豆蔻酰基化的。GCAP - 2的Ca2+依赖性构象开关的详细结构信息到目前为止是缺失的，因为没有确定Ca2+ - free状态的原子分辨率结构。肉豆蔻酰基部分的作用仍然知之甚少。现有的功能数据与在原型NCS蛋白recoverin中观察到的Ca2+‐肉豆蔻酰基开关不相容。对于同源的GCAP - 1，已经提出了一种不依赖于Ca2+的蛋白质结构内肉豆蔻基部分的隔离。在这篇文章中，我们比较了肉豆蔻酰基化和非肉豆蔻酰基化GCAP - 2在Ca2+结合和Ca2+游离形式下的热力学稳定性，以获得有关蛋白质Ca2+依赖构象开关性质的信息，并阐明其肉豆蔻酰基的作用。在没有Ca2+的情况下，肉豆蔻酰化和非肉豆蔻酰化形式的稳定性是难以区分的。Ca2+对两种形式的蛋白质都有稳定作用，对myr GCAP‐2的稳定作用更强。稳定性数据通过染料结合实验得到证实，该实验用于探测蛋白质的溶剂可接近的疏水表面。我们的研究结果强烈表明，肉豆荚基部分永久暴露在无Ca2+的GCAP - 2中，而它在Ca2+结合状态下与蛋白质结构的疏水部分相互作用。
Guanylate cyclase activating protein‐2 (GCAP‐2) is a Ca2+‐binding protein of the neuronal calcium sensor (NCS) family. Ca2+‐free GCAP‐2 activates the retinal rod outer segment guanylate cyclases ROS‐GC1 and 2. Native GCAP‐2 is N‐terminally myristoylated. Detailed structural information on the Ca2+‐dependent conformational switch of GCAP‐2 is missing so far, as no atomic resolution structures of the Ca2+‐free state have been determined. The role of the myristoyl moiety remains poorly understood. Available functional data is incompatible with a Ca2+‐myristoyl switch as observed in the prototype NCS protein, recoverin. For the homologous GCAP‐1, a Ca2+‐independent sequestration of the myristoyl moiety inside the proteins structure has been proposed. In this article, we compare the thermodynamic stabilities of myristoylated and non‐myristoylated GCAP‐2 in their Ca2+‐bound and Ca2+‐free forms, respectively, to gain information on the nature of the Ca2+‐dependent conformational switch of the protein and shed some light on the role of its myristoyl group. In the absence of Ca2+, the stability of the myristoylated and non‐myristoylated forms was indistinguishable. Ca2+ exerted a stabilizing effect on both forms of the protein, which was significantly stronger for myr GCAP‐2. The stability data were corroborated by dye binding experiments performed to probe the solvent‐accessible hydrophobic surface of the protein. Our results strongly suggest that the myristoyl moiety is permanently solvent‐exposed in Ca2+‐free GCAP‐2, whereas it interacts with a hydrophobic part of the protein's structure in the Ca2+‐bound state.
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杆状转导蛋白α亚基氨基末端被异质脂肪酰化。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Neubert,TA;Johnson,RS;Hurley,JB;Walsh,KA
通讯作者：
Walsh,KA
影响因子：
5.7
作者：
Stephen, Ricardo;Bereta, Grzegorz;Sousa, Marcelo Carlos
通讯作者：
Sousa, Marcelo Carlos
DOI：
10.1073/pnas.84.9.2708
发表时间：
1987-05
影响因子：
11.1
作者：
D. Towler;S. Adams;S. R. Eubanks;D. S. Towery;E. Jackson-Machelski;L. Glaser;J. Gordon
通讯作者：
D. Towler;S. Adams;S. R. Eubanks;D. S. Towery;E. Jackson-Machelski;L. Glaser;J. Gordon
视网膜恢复素的 NH2 末端被一小类脂肪酸酰化。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Dizhoor,AM;Ericsson,LH;Johnson,RS;Kumar,S;Olshevskaya,E;Zozulya,S;Neubert,TA;Stryer,L;Hurley,JB;Walsh,KA
通讯作者：
Walsh,KA
影响因子：
5.6
作者：
R. Stephen;K. Palczewski;M. Sousa
通讯作者：
R. Stephen;K. Palczewski;M. Sousa