Template-directed synthesis of a small molecule-antisense conjugate targeting an mRNA structure.
Template-directed synthesis of a small molecule-antisense conjugate targeting an mRNA structure.
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针对 mRNA 结构的小分子反义缀合物的模板指导合成。
DOI：
10.1016/j.bioorg.2014.03.001
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发表时间：
2014
影响因子：
5.1
通讯作者：
Wolfe,MichaelS
中科院分区：
文献类型：
--
作者：
Liu,Yang;Rodriguez,Lilia;Wolfe,MichaelS
以特异性靶向mRNA中的结构特征仍然是一个巨大的化学挑战。编码tau蛋白的前体mRNA中外显子10附近的发夹结构控制其剪接，并且破坏该结构的痴呆症引起的突变增加外显子10剪接。我们先前报道了发现小分子，米托蒽醌（MTX）和类似物，其结合到tau RNA发夹结构和设计的二分反义寡核苷酸（ASO），同时结合到该发夹侧翼的不连续序列。在此，我们报告了使用tau RNA发夹和侧翼序列作为模板合成偶联至MTX的二分阿索。合成了一组六种MTX类似物，每种含有接头-叠氮化物，和一组十种二分ASO，每种含有支链接头-炔，并以组合方式测试它们在存在或不存在模板RNA的情况下缀合的能力。从60种反应混合物中鉴定出单一模板依赖性MTX-ASO缀合物，证明MTX和阿索前体可同时结合RNA模板并允许叠氮化物和炔的适当定位用于1，3-环加成。虽然MTX-ASO偶联物证明对于基于细胞的测定来说太具有细胞毒性，但偶联物在无细胞条件下比单独的MTX或二分阿索更有效地抑制tau外显子10剪接。
The targeting of structural features in mRNA with specificity remains a great chemical challenge. A hairpin structure near exon 10 in the pre-mRNA encoding the tau protein controls its splicing, and dementia-causing mutations that disrupt this structure increase exon 10 splicing. We previously reported the discovery of small molecules, mitoxantrone (MTX) and analogs, which bind to the tau RNA hairpin structure and the design of bipartite antisense oligonucleotides (ASOs) that simultaneously bind to the discontinuous sequences that flank this hairpin. Herein we report the synthesis of a bipartite ASO conjugated to MTX using the tau RNA hairpin and flanking sequences as a template. A set of six MTX analogs, each containing a linker-azide, and a set of ten bipartite ASOs, each containing a branched linker-alkyne, were synthesized and tested in combinatorial fashion for their ability to conjugate in the presence or absence of template RNA. A single template-dependent MTX–ASO conjugate was identified from among the 60 reaction mixtures, demonstrating that the MTX and ASO precursors could simultaneously bind the RNA template and allow proper positioning of azide and alkyne for 1,3-cycloaddition. While the MTX–ASO conjugate proved too cytotoxic for cell-based assays, the conjugate inhibited tau exon 10 splicing under cell-free conditions more effectively than MTX or bipartite ASO alone.