Autism-like behaviours and germline transmission in transgenic monkeys overexpressing MeCP2
Autism-like behaviours and germline transmission in transgenic monkeys overexpressing MeCP2
复制标题
过度表达 MeCP2 的转基因猴中的自闭症样行为和种系传播。
DOI：
10.1038/nature16533
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发表时间：
2016-02-04
期刊：
影响因子：
64.8
通讯作者：
Qiu, Zilong
中科院分区：
文献类型：
--
作者：
Liu, Zhen;Li, Xiao;Qiu, Zilong
甲基 - CpG结合蛋白2（MeCP2）在转录调控和微小RNA加工中具有关键作用（1 - 4）。在90%的瑞特综合征患者中发现了MECP2基因的突变，瑞特综合征是一种伴有自闭症表型的严重发育障碍（5）。包含MECP2的基因组片段重复会导致MECP2重复综合征，该综合征与自闭症谱系障碍有核心症状相同（6）。尽管Mecp2基因缺失的小鼠重现了瑞特综合征患者中大多数的发育和行为缺陷，但在MeCP2过表达的小鼠模型中很难识别出自闭症样行为（7,8）。在此我们报道，在大脑中表达人MeCP2的基于慢病毒的转基因食蟹猴（Macaca fascicularis）表现出自闭症样行为，并显示转基因的生殖系传递。通过对转基因猴脑组织进行蛋白质印迹和免疫染色证实了MECP2转基因的表达。通过基于深度测序的方法确定了转基因的基因组整合位点。与野生型猴子相比，MECP2转基因猴子表现出更高频率的重复性环形运动以及更强的应激反应，这是通过与威胁相关的焦虑和防御测试测量得出的（9）。在社交互动测试中，转基因猴子与同组内的野生型猴子互动较少，并且与其他转基因猴子配对时互动时间也减少。在威斯康星通用测试装置中，转基因猴子的认知功能基本正常，尽管有些猴子表现出刻板认知行为的迹象。值得注意的是，我们通过将一只F - 0转基因猴子的精子进行胞质内单精子注射，成功培育出了5只MECP2转基因猴子的F - 1后代，这表明在F - 1后代中几个MECP2转基因存在生殖系传递和孟德尔分离。此外，与年龄相似的野生型猴子相比，F - 1转基因猴子在成对测试时也表现出社交互动减少。总之，这些结果表明使用基因工程非人灵长类动物研究脑部疾病的可行性和可靠性。
Methyl-CpG binding protein 2 (MeCP2) has crucial roles in transcriptional regulation and microRNA processing(1-4). Mutations in the MECP2 gene are found in 90% of patients with Rett syndrome, a severe developmental disorder with autistic phenotypes(5). Duplications of MECP2-containing genomic segments cause the MECP2 duplication syndrome, which shares core symptoms with autism spectrum disorders(6). Although Mecp2-null mice recapitulate most developmental and behavioural defects seen in patients with Rett syndrome, it has been difficult to identify autism-like behaviours in the mouse model of MeCP2 overexpression(7,8). Here we report that lentivirus-based transgenic cynomolgus monkeys (Macaca fascicularis) expressing human MeCP2 in the brain exhibit autism-like behaviours and show germline transmission of the transgene. Expression of the MECP2 transgene was confirmed by western blotting and immunostaining of brain tissues of transgenic monkeys. Genomic integration sites of the transgenes were characterized by a deep-sequencing-based method. As compared to wild-type monkeys, MECP2 transgenic monkeys exhibited a higher frequency of repetitive circular locomotion and increased stress responses, as measured by the threat-related anxiety and defensive test(9). The transgenic monkeys showed less interaction with wild-type monkeys within the same group, and also a reduced interaction time when paired with other transgenic monkeys in social interaction tests. The cognitive functions of the transgenic monkeys were largely normal in the Wisconsin general test apparatus, although some showed signs of stereotypic cognitive behaviours. Notably, we succeeded in generating five F-1 offspring of MECP2 transgenic monkeys by intracytoplasmic sperm injection with sperm from one F-0 transgenic monkey, showing germline transmission and Mendelian segregation of several MECP2 transgenes in the F-1 progeny. Moreover, F-1 transgenic monkeys also showed reduced social interactions when tested in pairs, as compared to wild-type monkeys of similar age. Together, these results indicate the feasibility and reliability of using genetically engineered non-human primates to study brain disorders.