{"title":"Characterization of nuclease stability and poly(A)-binding protein binding activity of chemically modified poly(A) tail for in vivo applications","authors":"Atsushi Hashimoto, Yuma Kunitomo, Ittoku Kikuchi, Hiroki Yamada, Keiko Kobayashi, Kazuhiro Soshiroda, Hiromi Aman, Yasuaki Kimura, Junichiro Yamamoto, Yasuhisa Shiraishi, Satoshi Uchida, Hiroshi Abe and Hiroto Iwai","doi":"10.1039/D5CB00137D","DOIUrl":null,"url":null,"abstract":"<p >The poly(A) tail plays a crucial role in mRNA stability and translation efficiency. Chemical modification of the poly(A) tail is a promising approach for stabilizing mRNA against deadenylation. In this study, we investigated the effect of poly(A) chemical modifications using phosphorothioate (PS), 2′-fluoro (2′-F), 2′-<em>O</em>-methyl (2′-OMe), and 2′-<em>O</em>-methoxyethyl (2′-MOE) modifications. Notably, PS, 2′-OMe, and 2′-MOE modifications conferred resistance to CAF1, an enzyme responsible for deadenylation. Interestingly, only the PS modification retained the poly(A)-binding protein (PABP) binding activity, which is critical for translation, whereas 2′-F, 2′-OMe, and 2′-MOE modifications abolished this activity. Beyond the PS modification, the combination of 2′-F, 2′-OMe, and 2′-MOE modifications resulted in enhanced resistance to both CAF1 and other nucleases. Based on these results, a 12-nucleotide unmodified poly(A) sequence was inserted upstream of the modified poly(A) to confer both nuclease resistance and PABP-binding activity. Notably, the resulting poly(A) formulation significantly prolonged protein expression in cultured cells and mouse skin when applied to epidermal growth factor-encoding therapeutic mRNA. Collectively, this study presents a design concept for poly(A) chemical modifications to achieve durable protein expression from mRNA, offering a promising strategy for enhancing the function of mRNA-based therapeutics.</p>","PeriodicalId":40691,"journal":{"name":"RSC Chemical Biology","volume":" 10","pages":" 1616-1624"},"PeriodicalIF":3.1000,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12381655/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"RSC Chemical Biology","FirstCategoryId":"1085","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/cb/d5cb00137d","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The poly(A) tail plays a crucial role in mRNA stability and translation efficiency. Chemical modification of the poly(A) tail is a promising approach for stabilizing mRNA against deadenylation. In this study, we investigated the effect of poly(A) chemical modifications using phosphorothioate (PS), 2′-fluoro (2′-F), 2′-O-methyl (2′-OMe), and 2′-O-methoxyethyl (2′-MOE) modifications. Notably, PS, 2′-OMe, and 2′-MOE modifications conferred resistance to CAF1, an enzyme responsible for deadenylation. Interestingly, only the PS modification retained the poly(A)-binding protein (PABP) binding activity, which is critical for translation, whereas 2′-F, 2′-OMe, and 2′-MOE modifications abolished this activity. Beyond the PS modification, the combination of 2′-F, 2′-OMe, and 2′-MOE modifications resulted in enhanced resistance to both CAF1 and other nucleases. Based on these results, a 12-nucleotide unmodified poly(A) sequence was inserted upstream of the modified poly(A) to confer both nuclease resistance and PABP-binding activity. Notably, the resulting poly(A) formulation significantly prolonged protein expression in cultured cells and mouse skin when applied to epidermal growth factor-encoding therapeutic mRNA. Collectively, this study presents a design concept for poly(A) chemical modifications to achieve durable protein expression from mRNA, offering a promising strategy for enhancing the function of mRNA-based therapeutics.
poly(A) tail对mRNA的稳定性和翻译效率起着至关重要的作用。化学修饰聚(A)尾部是一种很有前途的方法,以稳定mRNA对死基化。在这项研究中,我们研究了聚(A)化学修饰的影响,包括磷硫酸盐(PS)、2'-氟(2'-F)、2'- o -甲基(2'-OMe)和2'- o -甲氧基乙基(2'-MOE)修饰。值得注意的是,PS、2'-OMe和2'-MOE修饰赋予了对CAF1(一种负责死基化的酶)的抗性。有趣的是,只有PS修饰保留了对翻译至关重要的聚(A)结合蛋白(PABP)结合活性,而2'-F、2'-OMe和2'-MOE修饰则消除了这种活性。除了PS修饰之外,2'-F、2'-OMe和2'-MOE修饰的组合导致对CAF1和其他核酸酶的抗性增强。基于这些结果,将一个12个核苷酸的未经修饰的聚(a)序列插入修饰的聚(a)上游,以获得核酸酶抗性和pabp结合活性。值得注意的是,当应用于表皮生长因子编码治疗mRNA时,所得到的聚(A)制剂显著延长了培养细胞和小鼠皮肤中的蛋白质表达。总的来说,本研究提出了一种多聚(a)化学修饰的设计概念,以实现mRNA的持久蛋白质表达,为增强基于mRNA的治疗方法的功能提供了一种有希望的策略。