THERAPEUTIC POTENTIAL OF DYSTROPHIN MINI-GENES

Duchenne肌营养不良症(DMD)是一种由dystrophin基因突变引起的X连锁隐性遗传病，是人类最常见的遗传病之一。不幸的是，这种致命的疾病没有治疗或治愈的方法。在论证基因治疗DMD的可行性方面已经取得了相当大的进展。然而，在基因治疗能够有效地应用于这种常见的遗传病之前，仍有许多问题需要解决。主要问题之一是病毒载体携带全长dystrophin基因(14kb)的能力有限。本申请建议通过构建缺失构建体来探索杆状结构域区域的功能作用，最终目标是识别具有治疗潜力的最小的dystrophin构建体，以解决这一问题。目的L将在转基因MDX(dystrophin缺陷型)小鼠中检测Dp260亚型dystrophin亚型逆转营养不良表型的功能。由于N端的截断，Dp260的cDNA只有7kb。目的2通过固相法和共沉淀法研究Dp260异构体和杆状结构域的肌动蛋白结合能力。Aim 3将使用转基因MDX小鼠测试多种多重缺失的组合，以寻找可能最小的功能性肌营养不良蛋白通过病毒载体传递。这些研究将有助于更好地了解Dstrophin的功能，并将有助于推动DMD基因治疗的发展。

Duchenne muscular dystrophy (DMD), an X-linked recessive disease caused by mutations in the dystrophin gene, is one of the most common human genetic diseases. Unfortunately, there is no treatment or cure for this lethal disorder. Considerable progress has been made in demonstrating the feasibility of gene therapy for DMD. Nevertheless, numerous issues still need to be addressed before gene therapy can be effectively applied to this common genetic disease. One of the main issues is the limited ability of viral vectors to carry the full-length dystrophin cDNA (14 kb). This application proposes to address this concern by exploring the functional role of the rod domain region through construction of deletion constructs with the ultimate goal of identifying the smallest dystrophin construct that has therapeutic potential. Aim l will test the functional capacity of the Dp260 isoform of dystrophin to reverse the dystrophic phenotype in transgenic mdx (Dystrophin-deficient) mice. The Dp260 cDNA is only 7 kb due to an N- terminal truncation. Aim 2 will explore the actin binding capacity of the Dp260 isoform and rod domain in vitro through solid-phase and co- sedimentation assays. Aim 3 will test various combinations of multiple deletions using transgenic mdx mice in order to find the smallest possible functional dystrophin for delivery via viral vectors. These studies will lead to a greater understanding of the function of dystrophin and will help advance the development of gene therapy for DMD.