Coding and Noncoding RNA Contributions to 22q11.2 Deletion Syndrome

项目总结/摘要 22q11.2缺失综合征（22q11.2del）是人类最常见的微缺失综合征， 影响约1/4000人。大多数患者在一个染色体拷贝上有3 Mb缺失 22q11.2，导致超过107个基因，46个蛋白质编码和其余的单倍不足 非编码RNA和假基因。出生时有这种缺失的孩子可能会有一系列的先天性 通常包括三种发育相关的异常;胸腺发育不全， 先天性心脏病（CHD）和甲状旁腺功能减退。大约60-70%的患者 由于胸腺发育不全导致T细胞输出减少而导致的免疫缺陷，临床上常 被称为迪乔治综合征导致缺陷的潜在机制 胸腺组织的形成/图案化仍然知之甚少。我们的结果，在 该研究的前一个周期，表明神经嵴来源的间充质细胞存在缺陷， 其形成胸腺囊和脉管系统并调节胸腺的扩张。在我们的第一 目的，咽器的发育异常导致形成一个 将测定发育不全胸腺。具体来说，神经嵴来源的间充质细胞 研究细胞在调节胸腺发育和扩张方面的作用。胚胎胸腺 22q11.2del的小鼠模型将用于再聚集胎儿胸腺器官培养物，以确定 间充质细胞在胸腺扩张过程中的作用。RNA测序方法， 包括单细胞RNA测序将用于确定间充质转录本是什么 参与这个过程。这些实验将补充人类的特征， 22q11.2del患者和正常对照的胸腺细胞。在携带22 q11.2del的人类中，沿着 在小鼠模型中，注意到出生后miRNA失调。在目标2中，我们将探讨 这些miRNA变化的结果使用了人类纵向研究的组合， 不同的小鼠模型。这将揭示miRNAs的失调是否会影响免疫功能， 与胸腺有关的功能。这两个目标的结果将使我们更好地发展 在各种临床环境中恢复胸腺功能的策略导致这种发育不全， 组织.

Project Summary/Abstract 22q11.2 deletion syndrome (22q11.2del) is the most com~mon human microdeletion syndrome known, affecting some 1/4000 individuals. Most patients have a 3 Mb deletion on one copy of chromosome 22q11.2, resulting in a haploinsufficiency of over 107 genes, 46 protein coding and the remainder noncoding RNAs and pseudogenes. Children born with this deletion can have a range of congenital anomalies that often include three that are developmentally linked; hypoplasia of the thymus, congenital heart defects (CHD), and hypoparathyroidism. Approximately 60-70% of the patients have an immunodeficiency due to reduced T cell output from a hypoplastic thymus and are often clinically referred to as having DiGeorge syndrome. The underlying mechanisms causing the defective formation/patterning of the thymic tissue remains poorly understood. Our results, obtained during the previous cycle of this grant, suggest a defect among the neural crest derived mesenchymal cells, which form the thymic capsule and vasculature and regulate the expansion of the thymus. In our first aim, the developmental abnormalities of the pharyngeal apparatus leading to the formation of a hypoplastic thymus will be determined. Specifically, the role of the neural crest-derived mesenchymal cells in regulating the development and expansion of the thymus will be studied. Embryonic thymii from mouse models of 22q11.2del will be used in reaggregate fetal thymic organ cultures to define the role of mesenchymal cells in the process of thymus expansion. RNA sequencing approaches, including single cell RNA sequencing will be used to determine what mesenchymal transcripts are involved in this process. These experiments will be complemented with a characterization of human thymii from 22q11.2del patients and normal controls. In humans with 22q11.2del along with the mouse models, there is a post-natal miRNA dysregulation noted. In aim 2, we will explore the consequence of these miRNA changes using a combination of longitudinal studies in humans and diverse mouse models. This will reveal whether the dysregulation of miRNAs impacts immune functions pertaining to the thymus. Results from the two aims will enable us to develop better strategies for restoring thymus functions in various clinical settings resulting in the hypoplasia of this tissue.