DNA methylation as a mechanism for reduced dendritic spine density in schizophrenia

7.项目概要/摘要。 精神分裂症（SZ）是一种毁灭性的精神疾病，治疗选择有限。大脑皮层破坏 电路是SZ病理学和病理生理学的关键特征。树突棘密度（DSD）降低， 皮质层3是在尸检研究中最一致观察到的皮质回路异常之一， SZ，影响多个脑区，包括上级颞回（STG）。减少DSD被认为是 在SZ的多个症状域的基础上，包括损害社会认知的听觉处理缺陷， 然而，对于幻听，有助于减少DSD的机制知之甚少。DNA 甲基化（DNAm），甲基基团添加到胞嘧啶核苷酸，是基因转录的调节剂。 考虑到（1）SZ受试者的大脑中DNAm发生了改变，以及（2）在其他情况下DNAm发生了改变， 以DSD异常为特征，DNAm是SZ中DSD减少的强有力的候选机制。尽管 有证据表明DNAm在调节DSD中的作用，DNAm与DSD减少之间的关系 在深圳，此前尚未进行过探索。我们提出的研究，以测试的假设，减少DSD在SZ 部分原因是由DNAm的改变引起的多个基因转录的改变。 首先，我们将在一个大的SZ-NPC队列中选择性地评估STG第3层的全基因组、位点特异性DNAm DSD已经被描述过了。然后，我们将磨练在DNAm-DSD的相关性， 在STG层3 PYR神经元中，DNAm-基因转录关系可能介导这些相关性。 最后，我们将通过使用CRISPR/Cas9系统来改变DNAm和DSD之间的因果关系， 以基因组区域特异性方式检测候选基因DNAm，并测量神经元培养物中的DSD。到 恭维这个研究项目，我已经制定了一个创新的，全面的，多学科的培训 计划让我顺利过渡到独立调查员 在完成拟议的研究和培训计划后，我将成为精神病表观遗传学的专家， 一般来说，并在应用尖端的方法来研究树突棘病理学在深圳，特别是。 很少有研究人员有必要的背景和培训，以连接多层次的调查- 临床观察/行为、回路、神经元、转录表达、表观遗传修饰和遗传修饰 代码-必要的创新和临床相关的贡献，以了解表观遗传 精神疾病的机制。正是有了这种独特的背景和训练的结合，我将 建立我的独立的，NIH资助的实验室，并在我的K23奖期间的第3年提交R 01资金。

7. Project Summary/Abstract. Schizophrenia (SZ) is a devastating psychiatric disorder with limited treatment options. Disruptions in cortical circuitry are a key feature of SZ pathology and pathophysiology. Reduced dendritic spine density (DSD) in cortical layer 3 is among the most consistently observed cortical circuit abnormalities in postmortem studies of SZ, affecting multiple brain regions including the superior temporal gyrus (STG). Reduced DSD is thought to underlie multiple symptom domains in SZ including auditory processing deficits that impair social cognition and auditory hallucinations, however, the mechanisms that contribute to reduced DSD are poorly understood. DNA methylation (DNAm), the addition of a methyl group to a cytosine nucleotide, is a regulator of gene transcription. Given that (1) DNAm is altered in the brains of SZ subjects and (2) DNAm is altered in other contexts characterized by DSD abnormalities, DNAm is a strong candidate mechanism for reduced DSD in SZ. Despite evidence suggesting a role for DNAm in regulation of DSD, the relationship between DNAm and reduced DSD in SZ has not previously been explored. We propose studies to test the hypothesis that reduced DSD in SZ results, in part, from the altered transcription of multiple genes caused by alterations in DNAm. First, we will assess genome-wide, site-specific DNAm selectively in layer 3 of STG in a large SZ-NPC cohort for which DSD has already been characterized. Then, we will hone in on the DNAm-DSD correlations, and the DNAm-gene transcription relationships that may mediate those correlations, in STG layer 3 PYR neurons. Finally, we will test the causal relationship between DNAm and DSD by using the CRISPR/Cas9 system to alter candidate gene DNAm in a genome-region-specific manner and measure DSD in neuron cultures. To compliment this research project, I have developed an innovative, comprehensive, and multidisciplinary training plan to facilitate my transition to independent investigator. Upon completion of the proposed research and training plans, I will be an expert in psychiatric epigenetics, generally, and in applying cutting-edge approaches to the study of dendritic spine pathology in SZ, specifically. Few researchers have the necessary background and training to connect the multiple levels of investigation— clinical observation/behavior, circuits, neurons, transcript expression, epigenetic modifications, and genetic code—necessary to make innovative and clinically-relevant contributions to understanding the epigenetic mechanisms of psychiatric disorders. It is with this unique combination of background and training, that I will establish my independent, NIH-funded lab and submit for R01 funding in year 3 of my K23 award period.