Systematic mutational analysis of peptide inhibition of the p53-MDM2/MDMX interactions.
Systematic mutational analysis of peptide inhibition of the p53-MDM2/MDMX interactions.
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DOI：
10.1016/j.jmb.2010.03.005
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发表时间：
2010-04-30
影响因子：
5.6
通讯作者：
Lu W
中科院分区：
文献类型：
--
作者：
Li C;Pazgier M;Li C;Yuan W;Liu M;Wei G;Lu WY;Lu W
抑制肿瘤抑制蛋白p53与其负调节因子MDM2和MDMX之间的相互作用在癌症生物学和药物设计中具有重要意义。我们之前报道了一种有效的十二肽抑制剂，称为PMI (TSFAEYWNLLSP)，可以抑制p53-MDM2和-MDMX的相互作用。PMI与p53竞争MDM2和MDMX结合，其亲和力比相同长度的17-28p53 （ETFSDLWKLLPE）高约两个数量级；这两种肽在复合物中采用几乎相同的α-螺旋构象，其中三个突出的疏水残基Phe， Trp和Leu主导PMI或17-28p53与MDM2和MDMX的结合。为了阐明PMI活性和特异性的分子决定因素，我们对PMI和17-28p53进行了系统的Ala扫描突变分析。我们对包括10个截断类似物在内的共35个肽段对MDM2和MDMX的结合亲和力进行了定量分析，完整地剖析了PMI和17-28p53的单个残基对MDM2和MDMX结合的能量贡献。重要的是，N8A突变使PMI成为迄今为止报道的MDM2和MDMX最有效的双特异性拮抗剂，其Kd值分别为490 pM和2.4 nM。N8A-PMI-25-109MDM2的共晶结构测定值为1.95 Å，证实了高亲和力肽与MDM2/MDMX的结合，除了优化分子间相互作用外，还需要非接触残基提高螺旋稳定性或倾向性。强大的经验结合数据和晶体结构为p53-MDM2/MDMX相互作用的肽抑制的计算研究提供了独特的机会。
Inhibition of the interaction between the tumor suppressor protein p53 and its negative regulators MDM2 and MDMX is of great interest in cancer biology and drug design. We previously reported a potent duodecimal peptide inhibitor, termed PMI (TSFAEYWNLLSP), of the p53-MDM2 and -MDMX interactions. PMI competes with p53 for MDM2 and MDMX binding at an affinity roughly two orders of magnitude higher than that of 17–28p53 (ETFSDLWKLLPE) of the same length; both peptides adopt nearly identical α-helical conformations in the complexes, where the three highlighted hydrophobic residues Phe, Trp and Leu dominate PMI or 17–28p53 binding to MDM2 and MDMX. To elucidate the molecular determinants for PMI activity and specificity, we performed a systematic Ala scanning mutational analysis of PMI and 17–28p53. The binding affinities for MDM2 and MDMX of a total of 35 peptides including 10 truncation analogs were quantified, affording a complete dissection of energetic contributions of individual residues of PMI and 17–28p53 to MDM2 and MDMX association. Importantly, the N8A mutation turned PMI into the most potent dual specific antagonist of MDM2 and MDMX reported to date, registering respective Kd values of 490 pM and 2.4 nM. The co-crystal structure of N8A-PMI-25–109MDM2 was determined at 1.95 Å, affirming that high-affinity peptide binding to MDM2/MDMX necessitates, in addition to optimized inter-molecular interactions, enhanced helix stability or propensity contributed by non-contact residues. The powerful empirical binding data and crystal structures present a unique opportunity for computational studies of peptide inhibition of the p53-MDM2/MDMX interactions.
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影响因子：
5.6
作者：
Bottger, A;Bottger, V;Lane, DP
通讯作者：
Lane, DP
影响因子：
5.6
作者：
Kalid, Ori;Ben-Tal, Nir
通讯作者：
Ben-Tal, Nir
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K
影响因子：
4
作者：
Marine, Jean-Christophe W.;Dyer, Michael A.;Jochemsen, Aart G.
通讯作者：
Jochemsen, Aart G.
影响因子：
16.6
作者：
Li, Chong;Pazgier, Marzena;Liu, Min;Lu, Wei-Yue;Lu, Wuyuan
通讯作者：
Lu, Wuyuan