Characterization and inhibition of a p38-like mitogen-activated protein kinase (MAPK) from Echinococcus multilocularis: Antiparasitic activities of p38 MAPK inhibitors
Characterization and inhibition of a p38-like mitogen-activated protein kinase (MAPK) from Echinococcus multilocularis: Antiparasitic activities of p38 MAPK inhibitors
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DOI：
10.1016/j.bcp.2008.08.020
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发表时间：
2008-10-30
影响因子：
5.8
通讯作者：
Brehm, Klaus
中科院分区：
文献类型：
--
作者：
Gelmedin, Verena;Caballero-Gamiz, Rocio;Brehm, Klaus
泡状棘球虫病(AE)是由狐绦虫多房棘球绦虫的后生幼虫阶段引起的，是一种威胁生命的疾病，治疗选择非常有限。为了寻找新的药物靶点，我们集中在细胞信号机制的因素上，并在此报告了一个新的基因Emmpk2的特征，该基因在寄生虫的幼虫阶段表达，编码有丝分裂原激活的蛋白激酶(MAPK)家族的一个成员。在氨基酸序列水平上，编码的蛋白EmMPK2与来自多种动物的p38MAPK有相当大的同源性，但也显示出几个明显的差异，特别是在参与酶活性调节的氨基酸残基上。在大肠杆菌中异源表达后，纯化的EmMPK2显示出显著的自磷酸化活性，并与最接近的人类同源物p38-α相比，对MAPK底物的基础活性显著提高。P38MAPKs的竞争性吡啶基咪唑抑制剂ML3403和SB202190可有效抑制EmMPK2的活性，且呈浓度依赖关系。当添加到体外培养的囊泡中时，SB202190特别是ML3403导致寄生虫EmMPK2的去磷酸化，并在不影响培养的哺乳动物细胞的浓度下有效地杀死寄生虫的囊泡。综上所述，这些结果确定了吡啶基咪唑类化合物是一类新的抗包虫病药物，EmMPK2是开发治疗泡状棘球绦虫药物的有希望的靶点。(C)2008 Elsevier Inc.保留所有权利。
Alveolar echinococcosis (AE), caused by the metacestode larval stage of the fox-tapeworm Echinococcus multilocularis, is a life-threatening disease with very limited treatment options. in search for novel drug targets, we concentrate on factors of the cellular signaling machinery and report herein the characterization of a novel gene, Emmpk2, which is expressed in the parasite's larval stage and which codes for a member of the mitogen-activated protein kinase (MAPK) family. On the amino acid sequence level, the encoded protein, EmMPK2, shares considerable homologies with p38 MAPKs from a wide variety of animal organisms but also displays several distinct differences, particularly in amino acid residues known to be involved in the regulation of enzyme activity. Upon heterologous expression in Escherichia coli, purified EmMPK2 showed prominent autophosphorylation activity and strongly elevated basal activity towards a MAPK substrate, when compared to the closest human orthologue, p38-alpha. EmMPK2 activity could be effectively inhibited in the presence of ML3403 and SB202190, two ATP-competitive pyridinyl imidazole inhibitors of p38 MAPKs, in a concentration-dependent manner. When added to in vitro cultivated metacestode vesicles, SB202190 and particularly ML3403 led to dephosphorylation of EmMPK2 in the parasite and effectively killed parasite vesicles at concentrations that did not affect cultivated mammalian cells. Taken together, these results identify pyridinyl imidazoles as a novel class of anti-Echinococcus compounds and EmMPK2 as a promising target for the development of drugs against alveolar echinococcosis. (C) 2008 Elsevier Inc. All rights reserved.