Gene Therapy for ALS with mutant SOD1 by ribozyme and catalytic DNA.

近年来，短干扰RNA （short interfering RNA, siRNA）被发现能够高效地切割RNA，因此我们将其与核酶和催化DNA在抑制靶基因表达方面的效率进行了比较。在培养细胞中，为野生型SOD1设计的siRNA比核酶和催化DNA更有效地抑制SOD1的表达。当单核苷酸交替位于siRNA意义序列5′侧9-13个核苷酸处时，可以识别单核苷酸交替。利用这一原理，我们成功制备了特异性抑制突变体G93A SOD1表达而不影响野生型SOD1表达的siRNA。为了有效地将siRNA传递到神经元，病毒载体的发展可能是必要的。首先，利用U6启动子和siRNA茎环序列构建了优质的siRNA表达DNA载体。其次，利用该表达盒，我们成功制作了表达sirna的腺病毒和腺伴随病毒载体。至此，我们完成了SOD1突变基因治疗ALS的第一步。

Recently, short interfering RNA (siRNA) has been found to cleave efficiently RNA, so that we compared its efficiency for the supprresion of expression of target gene with ribozyme and catalytic DNA. In culture cells the siRNA designed for wild-type SOD1 was much more efficient to suppress the expression of SOD1 than ribozyme and catalytic DNA. When single nucleotide alternation was positioned at 9-13th nucleotide from 5' side in the sense sequence of siRNA, it can recognize a single nucleotide alternation. Using this principle, we succeeded in making the siRNA which specifically suppress the expression of mutant G93A SOD1 without influencing that of the wild-type SOD1.For the efficient delivery of siRNA to neurons, development of the virus vectors might be necessary. First, excellent siRNA-expressing DNA vector was constructed when the U6 promotor and the stem-loop sequence of siRNA were used. Second, with this expression cassette, we successfully made siRNA-expressing adnovirus and adno-associate virus vectors. Therefore, we finish the first step of the gene therapy for ALS with mutant SOD1.