Wang Tong-Hong, Li Wan-Ting, Yu Szu-Hsien, Au Lo-Chun
Institute of Biotechnology in Medicine, Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China.
Oligonucleotides. 2008 Sep;18(3):295-9. doi: 10.1089/oli.2008.0138.
10-23 DNAzyme is an oligodeoxyribonucleotide-based ribonuclease. It consists of a 15-nt catalytic domain flanked by two target-specific complementary arms. It has been shown to cleave target mRNA effectively at purine (R)-pyrimidine (Y) dinucleotide. Taking advantage of this specific property, 10-23 DNAzyme was designed to cleave mRNA of a given allele at a unique RY dinucleotide while leaving the mRNA encoded from other alleles of the same gene intact. In this study, a p53-R249S (AGG-->AGT) mutant was tested. 10-23 DNAzyme was used to cut mutant mRNA at GT dinucleotide of codon 249. Both in vitro and in vivo studies showed that this DNAzyme could specifically cut the mutant p53 allele, leaving the wild-type unaffected. This proof-of-concept experiment provided a new way to knock down expression of a given allele with special single-base transversion.
10-23脱氧核酶是一种基于寡脱氧核糖核苷酸的核糖核酸酶。它由一个15个核苷酸的催化结构域组成，两侧是两个靶标特异性互补臂。已证明它能在嘌呤（R）-嘧啶（Y）二核苷酸处有效切割靶标mRNA。利用这一特性，设计了10-23脱氧核酶，使其在一个独特的RY二核苷酸处切割给定等位基因的mRNA，同时保持同一基因其他等位基因编码的mRNA完整。在本研究中，对p53-R249S（AGG→AGT）突变体进行了测试。使用10-23脱氧核酶在密码子249的GT二核苷酸处切割突变体mRNA。体外和体内研究均表明，这种脱氧核酶能特异性切割突变型p53等位基因，而不影响野生型。这一概念验证实验为通过特殊的单碱基颠换敲低给定等位基因的表达提供了一种新方法。
