Discovery of Novel Autism-Associated Variation in Brain Miniproteins

项目摘要 这份R 03提案描述了一项为期两年的研究计划，重点是调查以前未注释的 自闭症谱系障碍（ASD）的遗传病因。罕见遗传和新生遗传 变异是ASD的重要原因，但仅在~20%的家族中解释病因。此外，罕见 ASD相关的变异体已经在基因组的非编码区中被鉴定，但是功能性的变异体在基因组的非编码区中被鉴定。 这些发现的意义在很大程度上是未知的，代表了ASD遗传学中的关键知识空白。我们 最近完成了一项研究，以描绘人类大脑的mRNA翻译景观（“翻译组”）， 鉴定数千个编码<100个氨基酸的推定微蛋白的小开放阅读框（sORF）， 其中许多是从基因组的注释的非编码区翻译的。我们假设 微蛋白代表了一种未被重视的隐藏基因的缓存，其在疾病中的作用几乎完全是 未开发的为了解决小蛋白在ASD中的潜在作用，我们将利用最大的全基因组 ASD中的WGS数据集，以及我们新创建的人脑微蛋白图谱，以发现 基于罕见遗传和从头序列水平和结构水平与ASD风险相关的小蛋白基因 （目标1）。此外，我们的初步数据表明，许多微蛋白缺乏三维结构， 结构（本质上是无序的），并富含结合RNA的序列基序。传统的基于序列的 蛋白质的分析在短的、高度无序的小蛋白上将表现不佳。因此，在目标2中，我们 建立基于物理特征的分析范式来预测ASD相关的分子功能 迷你蛋白这项工作结合了发育神经科学、基因组学和计算神经科学的专业知识。 蛋白质生物学从R 03中获得的知识，包括识别新的ASD相关 基因，将构成未来研究的基础，以表征功能，细胞类型特异性和发育 调节人类大脑中的微蛋白，以及它们对ASD的贡献。我们的方法来 在遗传分析中结合以前未注释的微蛋白可以应用于其他神经系统， 非神经系统疾病，从而扩大了我们对人类疾病遗传结构的理解。

PROJECT SUMMARY This R03 proposal describes a two-year research plan focused on the investigation of previously unannotated miniproteins to the genetic etiology of Autism Spectrum Disorder (ASD). Rare inherited and de novo genetic variants are important causes of ASD, but explain the etiology in only ~20% of families. Furthermore, rare ASD-associated variants have been identified in noncoding regions of the genome, but the functional significance of those found is largely unknown, representing a critical knowledge gap in ASD genetics. We recently completed a study to profile the mRNA translational landscape (the “translatome”) of the human brain, identifying thousands of small open reading frames (sORFs) encoding putative miniproteins <100 amino acids, many of which are translated from annotated noncoding regions of the genome. We hypothesize that miniproteins represent an unappreciated cache of hidden genes whose role in disease is almost entirely unexplored. To address the potential role of miniproteins in ASD, we will leverage the largest whole-genome sequencing (WGS) dataset in ASD, as well as our newly created atlas of human brain miniproteins, to discover miniprotein genes associated with ASD risk based on rare inherited and de novo sequence-level and structural variants (Aim 1). Additionally, our preliminary data suggest that many miniproteins lack three-dimensional structure (intrinsically disordered) and are rich in sequence motifs that bind RNA. Traditional sequence-based analysis of proteins will perform poorly on short, highly disordered miniproteins. Therefore, in Aim 2, we will build physical feature-based analysis paradigms to predict the molecular function of ASD-associated miniproteins. This work combines expertise in developmental neuroscience, genomics, and computational protein biology. The knowledge gained from this R03, including the identification of new ASD-associated genes, will form the basis of future studies to characterize the function, cell type-specificity, and developmental regulation of miniproteins in the human brain, as well as their contribution to ASD. Our approach to incorporating previously unannotated miniproteins in genetic analysis can be applied to other neurologic and non-neurologic conditions, thereby expanding our understanding of the genetic architecture of human disease.