注意力缺陷多动症 （ADHD）为儿童期常见神经系统疾病，与大脑多巴胺信号有关，患者常伴有生物节律问题。申请人前期研究中发现斑马鱼钟基因per1b突变体和小鼠Per1突变体均表现出ADHD的症状，从而建立了第一个生物钟相关的ADHD疾病模型，然而生物钟对于大脑多巴胺信号的调控机制不明。前期实验中，我们对斑马鱼per1b突变体大脑进行了早晚两个点的小RNA深度测序，发现19个差异小RNA中有14个均靶向到多巴胺能神经元发育关键基因nurr1, 还有一个靶向到dbh 基因，且发现小鼠中PER1与NURR1在黑质多巴胺能神经元中共定位。本项目拟采用CRISPR基因编辑技术结合分子生物学手段明确钟控小RNA对ADHD的调控机制，寻找生物钟基因直接参与多巴胺信号调控的证据，同时结合临床，发展ADHD分子诊断标记。本项目的实施对阐明ADHD的发病机制具有重要意义，为ADHD的精确诊断与治疗提供理论依据。

Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children, and mainly caused by the imbalance of dopamine level in the brain. While ADHD patients often display circadian abnormalities such as sleep/wake cycle disorders. In our former researches, we found that zebrafish core circadian gene per1b mutant and Per1 knockout mice displayed hyperactivity, impulsivity and attention deficiency, mimic the human ADHD behaviors. Therefore, we generated the first ADHD disease animal model caused by circadian dysfunctions. However, the mechanisms that how circadian clocks regulate the dopamine signaling pathway and the development of dopaminergic neurons are still far from certain. Recently, we did small non coding RNA deep sequencing using small RNA extracted from zebrafish per1b mutant brain, and found that within 19 differential miRNAs, up to 14 miRNAs can target to nurr1 gene, the key protein controlling the dopaminergic neuron’s development, and one miRNA target to dopamine beta hydroxylase gene, dbh. We also found that the PER1 protein is co-localized with NURR1 in the dopaminergic neurons of mice substantia nigra (SN) region. Based on these new findings, we plan to clarify the mechanisms that how circadian controlled microRNAs regulate ADHD, and explore the evidences that the core circadian factors can directly take part in the dopamine signaling pathway; Meanwhile, we also try to develop new diagnosis molecular markers in the ADHD patients. This study will provide new theoretical and experimental basis for the accurate diagnosis, prevention and treatment of ADHD.