Intersection of signaling pathways and transcription factors regulating islet development

调节胰岛发育的信号通路和转录因子的交叉点

• 批准号: 10584990
• 负责人: PAUL J GADUE
• 金额: $ 64.52万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2027-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10584990
• 关键词: Affect; Alleles; B cell differentiation; B-Cell Development; B-Lymphocytes; Beta Cell; Binding; Binding Sites; Biological Models; CRISPR/Cas technology; Cell Differentiation process; Collaborations; Data; Development; Disease; Endocrine; Enhancers; Event; Family; Functional disorder; Funding; GATA4 gene; Gene Expression Regulation; Genetic; Genetic Models; Genetic Transcription; Genome; Goals; High-Throughput Nucleotide Sequencing; Human; Human Genetics; Impairment; Individual; Islet Cell; Islets of Langerhans; Loss of Heterozygosity; Molecular; Mus; Mutation; Non-Insulin-Dependent Diabetes Mellitus; Pancreas; Pancreatic Diseases; Pathogenesis; Pathway interactions; Patients; Phenotype; Population; Productivity; Publishing; Regulation; Regulatory Pathway; Role; Severities; Severity of illness; Signal Pathway; Signal Transduction; Specific qualifier value; System; Technology; Testing; Tretinoin; cofactor; developmental disease; differentiation protocol; endocrine pancreas development; experimental study; human model; human pluripotent stem cell; in vivo; induced pluripotent stem cell; insight; mouse genetics; mouse model; neonatal diabetes mellitus; novel; pancreas development; progenitor; protein protein interaction; synergism; transcription factor

Pancreas agenesis (PA) is a developmental disorder characterized by either a reduction or complete lack of pancreatic mass. Notably, heterozygous loss of GATA6 accounts for >60% of all human pancreas agenesis cases; however, the pancreatic phenotype within each individual can be incompletely penetrant, ranging from severe neonatal diabetes to mild adult onset diabetes due to beta cell dysfunction. These findings suggest that additional genetic modifiers may contribute to the pathogenesis caused by the reduction in GATA6 expression. During the previous funding period, the collaboration between the Gadue and Sussel labs leveraged the strengths of human induced pluripotent stem cell (hiPSC)-based pancreas differentiation and in vivo murine models of development to discover robust synergy between GATA6 and retinoic acid (RA) signaling in regulating several stages of pancreas development. Our findings suggest two novel concepts: (1) an unappreciated role for RA signaling during endocrine progenitor specification and (2) synergy between RA and specifically GATA6 (but not GATA4) is required to specify beta cells in both mice and humans. The primary goals of this renewal application are to use these complementary genetic model systems to better define this synergy and elucidate the mechanisms by which the intersection of RA signaling and GATA6 regulate pancreas development. Furthermore, we will explore how human mutations in GATA6 disrupt this interaction to influence disease severity. Our published studies combined with new preliminary data in both the mice and human models has led us to hypothesize that this conserved synergy between RA signaling and GATA6 gene regulation is essential for pancreas development and the combined disruption of these pathways contributes to pancreas and islet cell development. We will test this hypothesis with the following specific aims: 1) Establish the synergistic roles of RA/GATA6 during pancreatic endocrine and β cell development and identify the specific stages of the hiPSC-derived pancreas differentiation protocol that require a combination of RA signaling and GATA6 function for optimal beta cell development; 2) Determine the precise molecular mechanism(s) underlying the intersection of RARa and GATA6 in the regulation gene expression pathways that promote pancreatic islet differentiation; and 3) Define how patient specific GATA6 disease mutations affect RA/GATA6 synergy and downstream pathways during pancreas development. The experiments proposed in this application will provide substantial novel insight into the conserved regulatory pathways that are required for appropriate pancreas development and islet cell differentiation and will further inform how mutations in GATA6 cause a wide range of pancreatic phenotypes in humans.

胰腺发育不全（PA）是一种发育障碍，其特征是胰腺细胞减少或完全缺乏。 胰腺肿块值得注意的是，GATA 6的杂合缺失占所有人类胰腺发育不全的> 60 例;然而，每个个体内的胰腺表型可以是不完全渗透的，范围从 从严重的新生儿糖尿病到由于β细胞功能障碍引起的轻度成人发病糖尿病。这些发现表明 另外的遗传修饰剂可能有助于GATA 6表达减少引起的发病机制。 在上一个资助期间，Gadue和Sussel实验室之间的合作利用了 基于人诱导多能干细胞（hiPSC）的胰腺分化和体内鼠胰腺分化的强度 开发模型，以发现GATA 6和视黄酸（RA）信号传导之间的强大协同作用， 胰腺发育的几个阶段我们的研究结果提出了两个新的概念：（1）一个不受重视的作用 对于内分泌祖细胞特化过程中的RA信号传导，以及（2）RA与特异性GATA 6之间的协同作用 (but而不是GATA 4）是指定小鼠和人类中的β细胞所必需的。这次重建的主要目标 应用是使用这些互补的遗传模型系统，以更好地定义这种协同作用，并阐明 RA信号和GATA 6的交叉调节胰腺发育的机制。 此外，我们将探讨人类GATA 6突变如何破坏这种相互作用，影响疾病 严重性。我们发表的研究结合了小鼠和人类模型的新的初步数据， 我们假设RA信号传导和GATA 6基因调节之间的这种保守协同作用是 对胰腺发育至关重要，这些途径的联合破坏有助于 胰腺和胰岛细胞发育。我们将测试这个假设与以下具体目标：1）建立 RA/GATA 6在胰腺内分泌和β细胞发育过程中的协同作用，并确定特定的 hiPSC衍生的胰腺分化方案的阶段，其需要RA信号传导和 GATA 6在最佳β细胞发育中的功能; 2）确定潜在的精确分子机制 RAR α和GATA 6在促进胰岛细胞增殖的调控基因表达途径中的交叉作用 3）定义患者特异性GATA 6疾病突变如何影响RA/GATA 6协同作用， 胰腺发育过程中的下游通路。本申请中提出的实验将提供 实质性的新见解保守的调控途径，需要适当的胰腺 发育和胰岛细胞分化，并将进一步告知GATA 6突变如何引起广泛的胰岛细胞分化。 人类胰腺表型。