PDF(Pubmed)
Abstract：
Restricted repetitive behaviors (RRBs), which are associated with many different neurological and mental disorders, such as obsessive-compulsive disorder (OCD) and autism, are patterns of behavior with little variation and little obvious function. Paired Box 2 (Pax2) is a transcription factor that is expressed in many systems, including the kidney and the central nervous system. The protein that is encoded by Pax2 has been implicated in the development of the nervous system and neurodevelopmental disorders. In our previous study, Pax2 heterozygous gene knockout mice (Pax2+/- mice) showed abnormally increased self-grooming and impaired learning and memory abilities. However, it remains unclear which cell type is involved in this process. In this study, we deleted Pax2 only in the nervous system to determine the regulatory mechanism of Pax2 in RRBs.
In this study, Pax2 nervous system-specific knockout mice (Nestin-Pax2 mice) aged 6-8 weeks and Pax2 flox mice of the same age were recruited as the experimental group. Tamoxifen and vehicle were administered via intraperitoneal injection to induce Pax2 knockout after gene identification. Western blotting was used to detect Pax2 expression. After that, we assessed the general health of these two groups of mice. The self-grooming test, marble burying test and T-maze acquisition and reversal learning test were used to observe the lower-order and higher-order RRBs. The three-chamber test, Y-maze, and elevated plus-maze were used to assess social ability, spatial memory ability, and anxiety. Neural circuitry tracing and transcriptome sequencing (RNA-seq) were used to observe the abnormal neural circuitry, differentially expressed genes (DEGs) and signaling pathways affected by Pax2 gene knockout in the nervous system and the putative molecular mechanism.
(1) The Nestin-Pax2 mouse model was successfully constructed, and the Nestin-Pax2 mice showed decreased expression of Pax2. (2) Nestin-Pax2 mice showed increased self-grooming behavior and impaired T-maze reversal behavior compared with Pax2 flox mice. (3) An increased number of projection fibers can be found in the mPFC projecting to the CA1 and BLA, and a reduction in IGFBP2 can be found in the hippocampus of Nestin-Pax2 mice.
The results demonstrated that loss of Pax2 in the nervous system leads to restricted repetitive behaviors. The mechanism may be associated with impaired neural circuitry and a reduction in IGFBP2.
In this study, Pax2 nervous system-specific knockout mice (Nestin-Pax2 mice) aged 6-8 weeks and Pax2 flox mice of the same age were recruited as the experimental group. Tamoxifen and vehicle were administered via intraperitoneal injection to induce Pax2 knockout after gene identification. Western blotting was used to detect Pax2 expression. After that, we assessed the general health of these two groups of mice. The self-grooming test, marble burying test and T-maze acquisition and reversal learning test were used to observe the lower-order and higher-order RRBs. The three-chamber test, Y-maze, and elevated plus-maze were used to assess social ability, spatial memory ability, and anxiety. Neural circuitry tracing and transcriptome sequencing (RNA-seq) were used to observe the abnormal neural circuitry, differentially expressed genes (DEGs) and signaling pathways affected by Pax2 gene knockout in the nervous system and the putative molecular mechanism.
(1) The Nestin-Pax2 mouse model was successfully constructed, and the Nestin-Pax2 mice showed decreased expression of Pax2. (2) Nestin-Pax2 mice showed increased self-grooming behavior and impaired T-maze reversal behavior compared with Pax2 flox mice. (3) An increased number of projection fibers can be found in the mPFC projecting to the CA1 and BLA, and a reduction in IGFBP2 can be found in the hippocampus of Nestin-Pax2 mice.
The results demonstrated that loss of Pax2 in the nervous system leads to restricted repetitive behaviors. The mechanism may be associated with impaired neural circuitry and a reduction in IGFBP2.
摘要：
背景：受限重复行为(RRB)，与许多不同的神经和精神障碍有关，如强迫症（OCD）和自闭症，是变化不大、功能不明显的行为模式。配对盒2（Pax2）是一种在许多系统中表达的转录因子，包括肾脏和中枢神经系统.Pax2编码的蛋白质与神经系统和神经发育障碍的发展有关。在我们之前的研究中,Pax2杂合子基因敲除小鼠(Pax2+/-小鼠)表现出异常增加的自我修饰和受损的学习和记忆能力。然而,尚不清楚该过程涉及哪种细胞类型。在这项研究中,我们仅在神经系统中删除Pax2，以确定Pax2在RRB中的调控机制。
方法：在本研究中，招募6-8周龄的Pax2神经系统特异性敲除小鼠（Nestin-Pax2小鼠）和相同年龄的Pax2flox小鼠作为实验组。在基因鉴定后,通过腹膜内注射施用他莫昔芬和载体以诱导Pax2敲除。使用蛋白质印迹法检测Pax2表达。之后,我们评估了这两组小鼠的总体健康状况。自我修饰测试，采用大理石掩埋试验、T型迷宫采集和反转学习试验观察低阶和高阶RRB。三室测试，Y-迷宫,高架迷宫被用来评估社交能力，空间记忆能力，和焦虑。神经回路追踪和转录组测序（RNA-seq）用于观察异常的神经回路，Pax2基因敲除对神经系统差异表达基因(DEGs)和信号通路的影响及推测的分子机制。
结果：（1）成功构建了Nestin-Pax2小鼠模型，Nestin-Pax2小鼠显示Pax2表达降低。（2）与Pax2flox小鼠相比，Nestin-Pax2小鼠表现出增加的自我修饰行为和受损的T迷宫逆转行为。(3)在投射到CA1和BLA的mPFC中可以发现数量增加的投射纤维,在Nestin-Pax2小鼠的海马中可以发现IGFBP2的减少。
结论：结果表明，神经系统中Pax2的缺失导致重复行为受限。该机制可能与受损的神经回路和IGFBP2的减少有关。
方法：在本研究中，招募6-8周龄的Pax2神经系统特异性敲除小鼠（Nestin-Pax2小鼠）和相同年龄的Pax2flox小鼠作为实验组。在基因鉴定后,通过腹膜内注射施用他莫昔芬和载体以诱导Pax2敲除。使用蛋白质印迹法检测Pax2表达。之后,我们评估了这两组小鼠的总体健康状况。自我修饰测试，采用大理石掩埋试验、T型迷宫采集和反转学习试验观察低阶和高阶RRB。三室测试，Y-迷宫,高架迷宫被用来评估社交能力，空间记忆能力，和焦虑。神经回路追踪和转录组测序（RNA-seq）用于观察异常的神经回路，Pax2基因敲除对神经系统差异表达基因(DEGs)和信号通路的影响及推测的分子机制。
结果：（1）成功构建了Nestin-Pax2小鼠模型，Nestin-Pax2小鼠显示Pax2表达降低。（2）与Pax2flox小鼠相比，Nestin-Pax2小鼠表现出增加的自我修饰行为和受损的T迷宫逆转行为。(3)在投射到CA1和BLA的mPFC中可以发现数量增加的投射纤维,在Nestin-Pax2小鼠的海马中可以发现IGFBP2的减少。
结论：结果表明，神经系统中Pax2的缺失导致重复行为受限。该机制可能与受损的神经回路和IGFBP2的减少有关。
