Functional and genetic evidence that nucleoside transport is highly conserved in Leishmania species: Implications for pyrimidine-based chemotherapy
Functional and genetic evidence that nucleoside transport is highly conserved in Leishmania species: Implications for pyrimidine-based chemotherapy
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DOI：
10.1016/j.ijpddr.2017.04.003
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发表时间：
2017-08-01
影响因子：
4
通讯作者：
de Koning, Harry P.
中科院分区：
文献类型：
--
作者：
Alzahrani, Khalid J. H.;Ali, Juma A. M.;de Koning, Harry P.
利什曼嘧啶回收充满了酶抑制剂或抗代谢物治疗干预的机会。它们进入细胞取决于特定的转运体；因此，有必要确定各种利什曼原虫物种是否具有能够摄取药物的相似嘧啶转运体。在这里，我们报道了L. major和L. mexicana中嘧啶转运的综合表征。在这两个物种中均检测到两种尿苷/腺苷转运蛋白，其中一种转运尿嘧啶及其抗代谢产物5-氟尿嘧啶（5-FU）和5F，2‘脱氧尿嘧啶（5F,2’dUrd），命名为尿嘧啶-尿嘧啶转运蛋白1 (UUT1)；另一种转运蛋白介导腺苷、尿苷、5F、2'd和胸腺嘧啶的摄取，被命名为核苷转运蛋白1 （NT1）。为了验证报道的L. donovani的两个编码尿苷/腺苷转运蛋白的nt1样基因和一个编码肌苷转运蛋白的NT2基因的模型，我们克隆了相应的L. major和L. mexicana基因，分别在T. bruei中表达。与L. donovani的报道一致，这两个物种的nt1样基因介导了[H-3]-尿苷的腺苷敏感摄取，而不是[H-3]-肌苷的腺苷敏感摄取。相反，nt2样基因介导[H-3]-肌苷的摄取，但不介导[H-3]-尿苷的摄取。在所检测的嘧啶类抗代谢物中，5-FU和5F，2'dUrd是最有效的抗利什曼动物；对这两种类似物均产生抗性。在每种情况下，都发现耐药细胞失去了对诱导药物的运输能力。代谢组学分析发现，5-FU和5F-2'dUrd在两种利什曼原虫中的作用机制相似，只是脱氧核苷酸代谢发生了较大变化。我们得出结论，嘧啶回收系统在利什曼原虫中是高度保守的，这是发展以嘧啶为基础的化疗的重要信息。(C) 2017年作者。由Elsevier Ltd代表澳大利亚寄生虫学学会出版。
Leishmania pyrimidine salvage is replete with opportunities for therapeutic intervention with enzyme inhibitors or antimetabolites. Their uptake into cells depends upon specific transporters; therefore it is essential to establish whether various Leishmania species possess similar pyrimidine transporters capable of drug uptake. Here, we report a comprehensive characterization of pyrimidine transport in L. major and L. mexicana. In both species, two transporters for uridine/adenosine were detected, one of which also transported uracil and the antimetabolites 5-fluoruracil (5-FU) and 5F,2'deoxyuridine (5F,2'dUrd), and was designated uridine-uracil transporter 1 (UUT1); the other transporter mediated uptake of adenosine, uridine, 5F,2'dUrd and thymidine and was designated Nucleoside Transporter 1 (NT1). To verify the reported L. donovani model of two NT1-like genes encoding uridine/adenosine transporters, and an NT2 gene encoding an inosine transporter, we cloned the corresponding L. major and L. mexicana genes, expressing each in T. brucei. Consistent with the L. donovani reports, the NT1-like genes of either species mediated the adenosine-sensitive uptake of [H-3]-uridine but not of [H-3]-inosine. Conversely, the NT2-like genes mediated uptake of [H-3]-inosine but not [H-3]-uridine. Among pyrimidine antimetabolites tested, 5-FU and 5F,2'dUrd were the most effective antileishmanials; resistance to both analogs was induced in L. major and L. mexicana. In each case it was found that the resistant cells had lost the transport capacity for the inducing drug. Metabolomics analysis found that the mechanism of action of 5-FU and 5F-2'dUrd was similar in both Leishmania species, with major changes in deoxynucleotide metabolism. We conclude that the pyrimidine salvage system is highly conserved in Leishmania species essential information for the development of pyrimidine-based chemotherapy. (C) 2017 The Authors. Published by Elsevier Ltd on behalf of Australian Society for Parasitology.