mRNA Splicing Modulation in Familial Dysautonomia

家族性自主神经障碍是一种由剪接引起的遗传性感觉和自主神经病变。 IKBKAP基因突变。该突变导致IKBKAP mRNA外显子20的可变跳跃。 导致IKAP蛋白的组织特异性减少。我们已经证明，剪接在 神经系统，导致IKAP蛋白水平显著降低。尽管FD是隐性的， 患者保留了产生正常信使核糖核酸和蛋白质的能力，这一发现提供了一种令人兴奋的、直接的 通过剪接修饰开发治疗方法的方法。作为NINDS赞助的 神经生成药物筛选联盟，我们发现激动素，一种植物细胞分裂素，是一种有效的调节剂 信使核糖核酸剪接该化合物疗效显著，能恢复患者正常的IKAP蛋白水平 细胞在一周内培养。最近，我们还证明了激动素可以修饰IKBKAP的剪接 在体内转基因小鼠和人类FD携带者和患者中。在过去的三年里，我们已经 与NINDS Blueprint神经治疗网络合作进行药物化学和优化 目的是开发一种新型剪接调节剂化合物(SMC)作为治疗FD的药物。至 到目前为止，我们已经评估了520多种化合物，并确定了200多种具有显著 提高了效力和功效。这笔拨款的目的是详细研究我们的新一届SMC如何修改 信使核糖核酸剪接我们还将对我们的一家SMC进行临床前试验，以首次确定是否 通过修改体内剪接增加IKAP蛋白将改善新的FD小鼠的疾病表型 模特。最后，我们将确定与疾病相关的关键网络。这将为未来产生潜在的生物标志物 临床研究，新的靶向治疗途径，并将阐明调节感觉和 自主神经系统发育。尽管FD是一种发育障碍，但患者 终生被持续的、剧烈的神经元退化所困扰。我们认为，有效地增加 生命早期的IKAP水平可能有助于神经元的存活，并防止或延迟使人衰弱的步态、感觉和 随着患者年龄的增长，他们的认知能力下降。成功完成这笔赠款的目标将使我们能够 了解我们的SMC的作用机制，确定它们的作用在一种新的动物身上是否有效 疾病模型，并发现对IKAP蛋白的治疗性增加做出反应的基因网络。 这些都是我们继续向诊所攀登的基本步骤。

Familial dysautonomia (FD) is a hereditary sensory and autonomic neuropathy that is caused by a splice mutation in the IKBKAP gene. The mutation results in variable skipping of exon 20 in IKBKAP mRNA, which leads to a tissue-specific reduction of IKAP protein. We have shown that splicing is particularly poor in the nervous system, resulting in dramatically reduced levels of IKAP protein. Despite the fact that FD is recessive, patients retain the capacity to make both normal mRNA and protein, a discovery that offered an exciting, direct approach towards the development of therapies via splicing modification. As part of an NINDS sponsored Neurogeneration Drug Screening Consortium, we identified kinetin, a plant cytokinin, as a potent modulator of mRNA splicing. This compound has remarkable efficacy and can restore normal IKAP protein levels in patient cells within one week in culture. Recently, we have also demonstrated that kinetin can modify IKBKAP splicing in vivo in both transgenic mice and in human FD carriers and patients. Over the past three years, we have worked with the NINDS Blueprint Neurotherapeutics Network to perform medicinal chemistry and optimization of kinetin, with the goal of developing a novel splicing modulator compound (SMC) as a therapy for FD. To date, we have evaluated over 520 compounds and have identified more than 200 that have dramatically improved potency and efficacy. The goal of this grant is to study, in detail, how our new class of SMCs modify mRNA splicing. We will also perform a pre-clinical trial of one of our SMCs to determine, for the first time, if increasing IKAP protein by modifying splicing in vivo will improve disease phenotypes in a new FD mouse model. Lastly, we will identify critical disease-relevant networks. This will yield potential biomarkers for future clinical studies, new targetable pathways for therapy, and will also shed light on the regulation of sensory and autonomic nervous system development. Despite the fact that FD is a developmental disorder, patients are plagued by continued, drastic neuronal degeneration throughout life. We believe that effectively increasing IKAP levels early in life may support neuronal survival and prevent or delay the debilitating gait, sensory, and cognitive decline seen in patients as they age. Successful completion of the Aims of this grant will allow us to understand the mechanism of action of our SMCs, determine if their action is efficacious in a novel animal model of the disease, and uncover gene networks that respond to a therapeutic increase in IKAP protein. These are all fundamental steps as we continue the long climb towards the clinic.