NMR dynamics-derived insights into the binding properties of a peptide interacting with an SH2 domain
NMR dynamics-derived insights into the binding properties of a peptide interacting with an SH2 domain
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DOI：
10.1021/bi048641k
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发表时间：
2005-01-18
期刊：
影响因子：
2.9
通讯作者：
Forman-Kay, JD
中科院分区：
文献类型：
--
作者：
Finerty, PJ;Mittermaier, AK;Forman-Kay, JD
信号转导蛋白磷脂酶C-γ 1（PLC-γ 1）在其C-末端SH 2结构域（PLCC）结合β-血小板衍生生长因子受体（PDGFR）中的磷酸化Tyr-1021位点（pTyr-1021）时被激活。为了更好地理解的贡献，动力学结合，我们已经使用NMR弛豫实验来研究的运动特性的骨架酰胺和侧链甲基基团的肽衍生自PDGFR的pTyr-1021网站，无论是免费的和复杂的PLCC SH 2域。游离肽具有松弛性质，这对于小的非结构化聚合物是典型的，而结合肽的骨架对于结合位点的中心部分中的残基是最不灵活的，其中皮科至纳秒时间尺度运动的幅度朝向肽的C-末端增加。朝向末端的PY 1021肽的大幅度运动的增加与作为具有C-末端残基的状态的集合存在的结合肽一致，所述C-末端残基具有最宽的骨架构象分布，而中心结合位点中的残基是最受限制的。氘自旋弛豫实验表明，蛋白质-肽界面是高度动态的，这种流动性可能在调节相互作用的亲和力中发挥重要作用。
The signal transduction protein phospholipase C-gamma1 (PLC-gamma1) is activated when its C-terminal SH2 domain (PLCC) binds the phosphorylated Tyr-1021 site (pTyr-1021) in the beta-platelet-derived growth factor receptor (PDGFR). To better understand the contributions that dynamics make to binding, we have used NMR relaxation experiments to investigate the motional properties of backbone amide and side chain methyl groups in a peptide derived from the pTyr-1021 site of PDGFR, both free and in complex with the PLCC SH2 domain. The free peptide has relaxation properties that are typical for a small, unstructured polymer, while the backbone of the bound peptide is least flexible for residues in the central portion of the binding site with the amplitude of pico- to nanosecond time scale motions increasing toward the C-terminus of the peptide. The increase in large amplitude motion toward the end of the pY1021 peptide is consistent with the bound peptide existing as an ensemble of states with C-terminal residues having the broadest distribution of backbone conformations, while residues in the central binding site are the most restricted. Deuterium spin relaxation experiments establish that the protein-peptide interface is highly dynamic, and this mobility may play an important role in modulating the affinity of the interaction.