Genomic imprinting in circuits for social behavior

项目总结/摘要 主要的精神疾病，如精神分裂症（SZ）和重度抑郁症，涉及异常的社会和心理问题。 行为和发病通常发生在青春期后。SZ的遗传危险因素通常是杂合子 受影响的个体和临床表型可以是高度可变的。然而，造成这种情况的因素 表型变异和这些疾病的发病时间知之甚少。基因组 印迹是一种表观遗传机制，其导致母本或父本等位基因的优先表达， 一些基因。印记导致了影响遗传表型效应的起源父母效应。 突变。典型的印记涉及父母一方的等位基因的完全沉默， 基因。然而，在最近的一篇文章中，作者的实验室发现， 表现出母本或父本等位基因表达偏好的基因。这种现象被称为非典型印记。 与肝脏或肌肉相比，非典型印记在大脑中高度富集。使用一种新的等位基因- 特异性原位杂交方法，作者发现非典型印迹基因表现为单等位基因， 在脑细胞亚群中的表达，表明在脑细胞中存在高度细胞类型特异性的印记形式。 个脑袋目前，还不知道非典型印迹是否是一种细胞类型特异性的印迹形式， 个脑袋此外，该领域不知道印记在特定细胞类型中的基因的身份。 大脑，非规范印记是否会在青春期改变，或者社会行为是否会受到影响。的 发现酪氨酸羟化酶（Th）和多巴脱羧酶（Ddc）是非典型的印迹基因 在大脑的特定区域有母亲的等位基因偏好。TH和DDC合成单胺 神经递质，在社会行为和精神疾病中起重要作用。在这里，笔者将测试 单胺能回路中的非典型印迹效应是高度细胞型的假说 特定形式的印记，可以改变，以应对青春期的发展和影响社会 在精神疾病中扮演的角色。目的1（K99）将确定非典型印迹是否是一个细胞- 类型特定形式的印记在单胺系统，并揭示了身份的基因， 印记在分子定义的亚型单胺能神经元在大脑中。这些研究涉及 产生母本和父本等位基因特异性报告小鼠以在细胞水平上解析Ddc的印迹 和新的方法，在细胞水平上在分离的单胺能神经元从不同的印记 使用单细胞RNASeq的大脑区域。目标2（R00）将决定是否在非典型印迹 用印迹法研究了青春期视前区（POA）和弓状核（ARN）在不同发育阶段的变化， 青春期使用我们实验室开发的RNASeq方法。POA和ARN在青春期发育中起重要作用， 社会行为和初步的数据表明，非规范印记可以改变这些地区， 对荷尔蒙信号的反应在目标3（R00）中，Th和Ddc单一和复合突变小鼠将用于 确定非典型印迹效应是否影响相同途径功能中的基因 协同地放大父母对后代社会行为的影响。受影响的社会行为 在精神疾病将测试，包括侵略，社会偏好，社会承认，社会奖励和 生殖行为这些实验将为小鼠基因组工程提供必要的新培训 和基因组学（K99），并建立一个独立的研究计划（R00）的基础，重点是 非典型印记基因和激素信号在社会行为和心理健康中的作用。 本提案的K99部分将为主要研究者（PI）提供国家级研究培训 art CRISPR-Cas9介导的小鼠基因组工程，生物信息学和基因组学编程 分析和单细胞转录组学。职业发展到独立将包括正规教师 导师，共同导师和教师委员会会议，以确保研究和职业基准正在 以及时和适当的方式见面。导师团队将协助申请和谈判 教师职位的过程，独立的研究建议和工作会谈的准备，并把 在离开香港大学前， 犹他州。工作会谈和R01提案也将提交给"教师智囊团"，以获得批评 整个部门的反馈。首席研究员还将通过以下方式提高沟通技巧： 向系里和相关的期刊俱乐部介绍正在进行的研究， PI将有机会进行口头陈述的会议，并参加一个 犹他州大学开设的课程。结合独立研究计划的基础， 职业发展活动将确保PI为进入独立学院做好充分准备 在一个主要的研究型大学的位置，并成为一个领导者，在印迹领域，社会 行为和心理健康。

Project Summary/Abstract Major psychiatric disorders, such as schizophrenia (SZ) and major depression, involve abnormal social behaviors and onset typically occurs after puberty. The genetic risk factors for SZ are frequently heterozygous in affected individuals and the clinical phenotypes can be highly variable. However, the factors that contribute to phenotypic variance and the timing of the onset of these disorders are poorly understood. Genomic imprinting is an epigenetic mechanism that causes preferential expression of the maternal or paternal allele for some genes. Imprinting causes parent-of-origin effects that influence the phenotypic effects of inherited mutations. Canonical imprinting involves complete silencing of one parent's allele and impacts a small number of genes. However, in a recent publication, the author's lab discovered that hundreds of genes in the mouse that exhibit a maternal or paternal allele expression bias. This phenomenon is called noncanonical imprinting. Noncanonical imprinting is highly enriched in the brain compared to the liver or muscle. Using a novel allele- specific in situ hybridization approach, the author found that noncanonical imprinted genes exhibit monoallelic expression in subpopulations of cells in the brain, suggesting a highly cell-type specific form of imprinting in the brain. Currently, it is not known whether noncanonical imprinting is a cell-type specific form of imprinting in the brain. Further, the field does not know the identity of the genes that are imprinted in specific cell-types of the brain, whether noncanonical imprinting can change at puberty or whether social behaviors are impacted. The author found that tyrosine hydroxylase (Th) and dopa decarboxylase (Ddc) are noncanonical imprinted genes with a maternal allele bias in specific regions of the brain. TH and DDC synthesize monoamine neurotransmitters, which have important roles in social behavior and mental illness. Here, the author will test the hypothesis that noncanonical imprinting effects in monoaminergic circuits are a highly cell-type specific form of imprinting that can change in response to pubertal development and impact social behaviors with roles in mental illness. Aim 1 (K99) will determine whether noncanonical imprinting is a cell- type specific form of imprinting in the monoamine system and uncover the identity of the genes that are imprinted in molecularly-defined subtypes of monoaminergic neurons in the brain. These studies involve generating maternal and paternal allele-specific reporter mice to resolve imprinting at the cellular level for Ddc and new methods to profile imprinting at the cellular level in isolated monoaminergic neurons from different brain regions using single-cell RNASeq. Aim 2 (R00) will determine whether noncanonical imprinting in the preoptic area (POA) and arcuate nucleus (ARN) changes at puberty by profiling imprinting before and after puberty using RNASeq methods developed in our lab. The POA and ARN play important roles in puberty and social behaviors and preliminary data shows that noncanonical imprinting can change in these regions in response to hormonal signaling. In Aim 3 (R00), Th and Ddc single and compound mutant mice will be used to determine whether noncanonical imprinting effects impacting genes in the same pathway function synergistically to amplify parental influences on offspring social behaviors. Social behaviors that are impacted in mental illness will be tested, including aggression, social preference, social recognition, social reward and reproductive behaviors. These experiments will provide essential new training in mouse genome engineering and genomics (K99) and establish the foundations for an independent research program (R00) focused on the roles of noncanonical imprinted genes and hormone signaling in social behaviors and mental health. The K99 portion of this proposal will provide the principle investigator (PI) with research training in state-of-the art CRISPR-Cas9 mediated mouse genome engineering, programming for bioinformatics and genomic analysis, and single cell transcriptomics. Career development to independence will consist of regular faculty mentor, co-mentor, and faculty committee meetings to ensure that research and career benchmarks are being met in a timely and appropriate fashion. The mentorship team will aid in the application and negotiation process for faculty positions, the preparation of an independent research proposal and job talks, and putting together the Aims and Research Strategy for the PI's first R01 grant application before leaving the University of Utah. The job talks and R01 proposals will also be presented to the “Faculty Think Tank” to get critical feedback from the whole department. The principle investigator will also improve communication skills by presenting research in progress talks to the department and relevant journal clubs, attending scientific meetings where the PI will have an opportunity to give oral presentations, and attending a grantsmanship course offered at the University of Utah. Combined with the foundation of the independent research program, the career development activities will ensure that the PI is well prepared to enter an independent faculty position at a major research oriented university and emerge as a leader in the fields of imprinting, social behavior and mental health.