Cell-based assays to detect inhibitors of fungal mRNA capping enzymes and characterization of sinefungin as a cap methyltransferase inhibitor
Cell-based assays to detect inhibitors of fungal mRNA capping enzymes and characterization of sinefungin as a cap methyltransferase inhibitor
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DOI：
10.1177/1087057104273333
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发表时间：
2005-06-01
影响因子：
--
通讯作者：
Parent, S
中科院分区：
文献类型：
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作者：
Chrebet, G;Wisniewski, D;Parent, S
真核mRNAs 5‘端的m7GpppN帽对于转录的稳定性和翻译是重要的。产生mRNA帽的三种酶活性包括RNA 5‘-三磷酸酶、RNA鸟苷酸转移酶和RNA(鸟嘌呤-7-)-甲基转移酶。编码这些酶的基因的物理组织在哺乳动物细胞和酵母、真菌或病毒之间是不同的。哺乳动物细胞的RNA三磷酸酶所用的催化机制也不同于酵母、真菌或病毒的酶。这些结构和功能上的差异表明，mRNA封顶的抑制剂可能是有用的抗真菌或抗病毒药物。作者描述了几种以全细胞酵母为基础的分析方法，用于鉴定和表征真菌mRNA封顶的抑制物。他们还报告了在检测中对天然产物新诺明的鉴定和表征。他们对这种S-腺苷蛋氨酸类似物的表征表明，它抑制mRNA帽甲基转移酶，并表现出对酵母ABD1酶和真菌CCM1酶的大约5-10倍的特异性，而不是在酵母细胞中表达的人HCM1酶。
The m7GpppN cap at the 5' end of eukaryotic mRNAs is important for transcript stability and translation. Three enzymatic activities that generate the mRNA cap include an RNA 5'-triphosphatase, an RNA guanylyltransferase, and an RNA (guanine-7-)-methyltransferase. The physical organization of the genes encoding these enzymes differs between mammalian cells and yeast, fungi, or viruses. The catalytic mechanism used by the RNA triphosphatases of mammalian cells also differs from that used by the yeast, fungal, or viral enzymes. These structural and functional differences suggest that inhibitors of mRNA capping might be useful antifungal or antiviral agents. The authors describe several whole-cell yeast-based assays developed to identify and characterize inhibitors of fungal mRNA capping. They also report the identification and characterization of the natural product sinefungin in the assays. Their characterization of this S-adenosylmethionine analog suggests that it inhibits mRNA cap methyltransferases and exhibits approximately 5- to 10-fold specificity for the yeast ABD1 and fungal CCM1 enzymes over the human Hcm1 enzyme expressed in yeast cells.