Molecular Besis of MeCP2 null-mutation Model Mouse and Gene Therapy

Rett综合征(RTT)是一种神经发育障碍，与甲基CpG结合蛋白2(MeCP2)突变有关。然而，目前尚不清楚基因型和表型之间的相关性。我们对219例RTT患者进行了MeCP2分析。在145名患者中发现了45种不同的突变(66.2%)。在经典RTT中，T158M是McCPZ最常见的错义突变，占19.1%，其次是R168X(14.8%)、R270X(13.0%)、R255X(9.6%)和R294X(6.1%)。R133C(33.3%)和R306C(23.3%)两个错义突变和R294X(13.3%)无义突变在30例不典型RTT患者中常见，包括保留的语音变体。已知的导致RTT样神经症状的半合子(-/y)雄性(-/y)小鼠的MeCP2缺失。我们用腺病毒载体将MeCP2基因导入纹状体，并与Ad.lacZ感染(对照)进行比较。39日龄和40日龄MeCP2-/Y小鼠，分别在4天和7天后进行多项行为学检查。每组7例。Ad.LacZ处理的小鼠运动能力进行性恶化，Ad.MeCP2处理的MeCP2-/Y小鼠的运动活动明显减弱。然后，我们利用成年雌性MeCP2-/+小鼠进行了在体腺病毒MeCP2基因导入双侧纹状体内前后的行为学研究。治疗后，大多数小鼠的运动能力明显改善。治疗效果在注射Ad.McCP-2后几周内达到显著水平，但在注射Ad.McCP-2后6周达到最大水平。所有表现为自我损伤的MeCP2-/+小鼠都通过McCP2基因治疗完全治愈了这些症状。综上所述，RTT是可逆的，在出生后和发病时，MeCP2的表达是可逆的，并且MeCP2在控制纹状体的运动和情绪方面起着至关重要的作用。

Rett syndrome (RTT) is a neurodevelopmental disorder, associated with mutations in the methyl-CpG-binding protein 2 (MeCP2). However, it is unknown the correlation between genotype and the phenotype yet.We performed MeCP2 analysis in 219 patients with RTT. A total of 45 different mutations were identified in 145 patients (66.2%). A missense mutation, T158M was the most common mutation of McCPZ, identified in 19.1%, followed by four nonsense mutations, R168X(14.8%), R270X(13.0%), R255X(9.6%), and R294X(6.1%) in classical RTT. Two missense mutation, R133C (33.3%), and R306C (23.3%), and a nonsense mutation, R294X (13.3%), were common in 30 patients with atypical RTT, including the preserved speech variant. Deletion of MeCP2 in hemizygous male (-/y) mice known to leads to RTT-like neurological symptoms. We transducted MeCP2 gene into the striaturn using adenoviral vector and compared to an infection of Ad.lacZ (control). The, MeCP2-/Y mice at 39 or 40 days old, several behavioral studies were performed 4 and 7 days later. (n=7 each group). The progressive deterioration of locomotion activity see in the Ad.LacZ-treated mice and there was significantly attenuated is the Ad.MeCP2-treated MeCP2-/Y mice. Then we performed the behavior studies before and after in vivo adenoviral MeCP2 gene transduction into the both striatum using the adult female MeCP2-/+ mice. The improvement of the impaired locomotors activity was clearly recognized in most of mice after the treatment. The therapeutic effects were met conspicuous within a few weeks, but then increased and reaches at the maximum level at 6 weeks after Ad.McCP 2 injection. All of the MeCP2 -/+ mice that had represented self-injuries were completely cured of these symptoms by McCP2 gene therapy. In conclusion, RTT is reversible by MeCP2 expression after birth and the onset, and MeCP2 plays essential roles in controlling locomotion and emotion in the striatum.