Distinct patterns of activation-dependent changes in conformational mobility between ERK1 and ERK2.
Distinct patterns of activation-dependent changes in conformational mobility between ERK1 and ERK2.
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DOI：
10.1016/j.ijms.2010.08.020
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发表时间：
2011-04
影响因子：
1.8
通讯作者：
Ahn NG
中科院分区：
文献类型：
--
作者：
Ring AY;Sours KM;Lee T;Ahn NG
通过质谱法（HX-MS）进行的氢/氘交换测量可用于报告折叠蛋白质内的局部构象迁移率，其中交换主要通过结构中的低能量波动发生，从而允许瞬时溶剂暴露。构象迁移率的变化可能会影响蛋白质功能，即使在结构变化是不可观察的情况下。先前对MAP激酶ERK 2的研究表明，激活后HX的增加发生在保守的N-和C-末端结构域之间的铰链处，这可以归因于骨架柔性的增强。这意味着激酶激活调节结构域间的闭合，并得到两种核苷酸结合模式的证据支持，这两种模式分别与ERK 2的活性与非活性形式中的闭合与开放构象一致。因此，ERK 2的磷酸化通过调节铰链的灵活性释放了对结构域间闭合的限制。在这项研究中，我们研究了ERK 1，它与ERK 2有90%的序列同一性。ERK 1的HX-MS测量结果显示与ERK 2在整体氘代方面相似，与其相似的三级结构一致。然而，HX的模式，在ERK 1激活后改变的ERK 2不同。特别是，HX在铰链区激活ERK 2后的改变没有发生在ERK 1，这表明这两种酶不同的铰链流动性和域间关闭的调节。与此一致，核苷酸结合的HX-MS测量表明，ERK 1的非活性和活性形式都显示了结构域闭合。我们的结论是，虽然ERK 1和ERK 2是密切相关的一级序列和三级结构，他们利用不同的机制，通过域间相互作用控制酶的功能。
Hydrogen/deuterium exchange measurements by mass spectrometry (HX-MS) can be used to report localized conformational mobility within folded proteins, where exchange predominantly occurs through low energy fluctuations in structure, allowing transient solvent exposure. Changes in conformational mobility may impact protein function, even in cases where structural changes are unobservable. Previous studies of the MAP kinase, ERK2, revealed increases in HX upon activation occured at the hinge between conserved N- and C-terminal domains, which could be ascribed to enhanced backbone flexibility. This implied that kinase activation modulates interdomain closure, and was supported by evidence for two modes of nucleotide binding that were consistent with closed vs open conformations in active vs inactive forms of ERK2, respectively. Thus, phosphorylation of ERK2 releases constraints to interdomain closure, by modulating hinge flexibility. In this study, we examined ERK1, which shares 90% sequence identity with ERK2. HX-MS measurements of ERK1 showed similarities with ERK2 in overall deuteration, consistent with their similar tertiary structures. However, the patterns of HX that were altered upon activation of ERK1 differed from those in ERK2. In particular, alterations in HX at the hinge region upon activation of ERK2 did not occur in ERK1, suggesting that the two enzymes differ with respect to their regulation of hinge mobility and interdomain closure. In agreement, HX-MS measurements of nucleotide binding suggested revealed domain closure in both inactive and active forms of ERK1. We conclude that although ERK1 and ERK2 are closely related with respect to primary sequence and tertiary structure, they utilize distinct mechanisms for controlling enzyme function through interdomain interactions.
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影响因子：
3.4
作者：
Hoofnagle, AN;Stoner, JW;Ahn, NG
通讯作者：
Ahn, NG
DOI：
10.1073/pnas.94.6.2327
发表时间：
1997-03-18
影响因子：
11.1
作者：
Wang, ZL;Harkins, PC;Goldsmith, EJ
通讯作者：
Goldsmith, EJ
DOI：
10.1016/j.bbrc.2008.10.127
发表时间：
2008-12-26
影响因子：
3.1
作者：
Kinoshita, Takayoshi;Yoshida, Ikuyo;Tada, Toshiji
通讯作者：
Tada, Toshiji
影响因子：
64.5
作者：
Canagarajah, BJ;Khokhlatchev, A;Goldsmith, EJ
通讯作者：
Goldsmith, EJ
DOI：
10.1073/pnas.0608849103
发表时间：
2006-11-28
影响因子：
11.1
作者：
Emrick, Michelle A.;Lee, Thomas;Ahn, Natalie G.
通讯作者：
Ahn, Natalie G.