Mono-anionic phosphopeptides produced by unexpected histidine alkylation exhibit high Plk1 polo-box domain-binding affinities and enhanced antiproliferative effects in HeLa cells.
Mono-anionic phosphopeptides produced by unexpected histidine alkylation exhibit high Plk1 polo-box domain-binding affinities and enhanced antiproliferative effects in HeLa cells.
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意外的组氨酸烷基化产生的单开发磷酸肽表现出高的PLK1 Polo-box结构域结合亲和力，并增强了HELA细胞中的抗增殖作用。
DOI：
10.1002/bip.22569
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发表时间：
2014-11
期刊：
影响因子：
2.9
通讯作者：
Burke TR Jr
中科院分区：
文献类型：
--
作者：
Qian WJ;Park JE;Lim D;Lai CC;Kelley JA;Park SY;Lee KW;Yaffe MB;Lee KS;Burke TR Jr
polo 样激酶 1 (Plk1) polo 盒结构域 (PBD) 与包含磷酸苏氨酸 (pThr)/磷酸丝氨酸 (pSer) 的序列的结合对于 Plk1 的正常功能至关重要。尽管高亲和力的合成含 pThr 肽为开发 PBD 导向抑制剂提供了起点，但迄今为止，此类肽在全细胞测定中的功效一直很差。这可能反映了有限的细胞膜渗透性，部分原因是磷酰基或其模拟物的双阴离子性质。在我们当前的论文中，我们报告了已经带有 N(π)-烷基的组氨酸残基发生意外的树脂上 N(τ)-烷基化。这产生了含阳离子咪唑的 pThr 肽，其中几种在细胞外测定中表现出个位数纳摩尔 PBD 结合亲和力，并在完整细胞中提高了抗有丝分裂功效。我们通过应用生物可逆新戊酰氧基甲基 (POM) 磷酰基保护进一步增强了这些肽的细胞功效。我们当前研究中提出的新结构见解，包括分子内电荷掩蔽的潜在用途，可能有助于进一步开发 PBD 结合肽和肽模拟物。
Binding of polo-like kinase 1 (Plk1) polo-box domains (PBDs) to phosphothreonine (pThr)/phosphoserine (pSer)-containing sequences is critical for the proper function of Plk1. Although high-affinity synthetic pThr-containing peptides provide starting points for developing PBD-directed inhibitors, to date the efficacy of such peptides in whole cell assays has been poor. This potentially reflects limited cell membrane permeability arising, in part, from the di-anionic nature of the phosphoryl group or its mimetics. In our current paper we report the unanticipated on-resin N(τ)-alkylation of histidine residues already bearing a N(π)- alkyl group. This resulted in cationic imidazolium-containing pThr peptides, several of which exhibit single-digit nanomolar PBD-binding affinities in extracellular assays and improved antimitotic efficacies in intact cells. We enhanced the cellular efficacies of these peptides further by applying bio-reversible pivaloyloxymethyl (POM) phosphoryl protection. New structural insights presented in our current study, including the potential utility of intramolecular charge masking, may be useful for the further development of PBD-binding peptides and peptide mimetics.