The Diversity Outbred Diabetes Project

项目摘要/摘要 2型糖尿病(T2D)是胰岛素需求增加和胰腺β-1功能障碍的结果。 细胞通过分泌足够量的胰岛素来满足这一需求。人类发现的大多数基因座 T2D的遗传学研究影响β细胞的发育、质量和/或功能。然而，还有很多事情是未知的 关于β细胞如何在营养刺激下分泌胰岛素。我们对胰岛素进行了基因筛查 从483只多样性近交系(DO)小鼠分离的233,447个体外胰岛的分泌。The Do 小鼠来自8个近交系小鼠，占所有小鼠品系遗传多样性的80%左右。 它们拥有与整个人类种群一样多的遗传多样性；大约4000万个单核苷酸 多态现象。DO小鼠已经保存了30代，积累了足够的减数分裂 重组，以实现病理生理表型的高分辨率映射。我们的基因筛查 确定了影响胰岛素分泌或胰岛素或胰高血糖素含量的30个基因座。利用我们的基因流水线 在鉴定过程中，我们选择了两个基因：hank和Zfp148进行进一步的研究。我们推导出了一种全身击倒 Hunk和Zfp148的β细胞特异性敲除。这两种基因敲除小鼠的胰岛分泌更多的胰岛素 对营养刺激的反应比对照组小鼠要好。大块头是一种蛋白激酶，因此我们将确定底物 来发现它是如何调节胰岛素分泌的。Zfp148是一种转录因子。因此，我们将标识 Zfp148的直接转录靶点。我们将应用我们的生物信息学管道从 在我们的筛查中确定的30个基因座，并将它们提供给研究社区。功能研究将是 在基因编辑的小鼠、基因编辑的人类ES来源的β细胞和人类胰岛中进行。这些 研究将发现与β细胞功能和T2D易感性有关的新基因和新途径。

PROJECT SUMMARY/ABSTRACT Type 2 diabetes (T2D) is the result of an increased demand for insulin along with an inability of pancreatic β- cells to meet this demand by secreting sufficient amounts of insulin. The majority of gene loci identified by human genetic studies of T2D affect β-cell development, mass, and/or function. Yet, there is a great deal that is unknown about how β-cells secrete insulin in response to nutrient stimuli. We carried out a genetic screen of insulin secretion in 233,447 pancreatic islets ex vivo that were isolated from 483 Diversity Outbred (DO) mice. The DO mice were derived from 8 inbred mouse strains representing ~80% of the genetic diversity of all mouse strains. They have as much genetic diversity as the entire human population; ~40 million single nucleotide polymorphisms. The DO mice have been maintained for >30 generations, accumulating enough meiotic recombinations to enable high-resolution mapping of pathophysiological phenotypes. Our genetic screen identified 30 gene loci that affect insulin secretion or content of insulin or glucagon. Using our pipeline for gene identification, we chose two genes for further study, Hunk and Zfp148. We derived a whole-body knockout of Hunk and a β-cell-specific knockout of Zfp148. Islets from both of these knockout mice secreted more insulin in response to nutrient stimulation than control mice. Hunk is a protein kinase, thus we will identify the substrates of Hunk to discover how it regulates insulin secretion. Zfp148 is a transcription factor. Thus, we will identify the direct transcriptional targets of Zfp148. We will apply our bioinformatic pipeline to identify additional genes from the 30 gene loci identified in our screen and provide them to the research community. Functional studies will be performed in genetically edited mice, genetically edited human ES-derived β-cells, and human islets. These studies will discover novel genes and pathways involved in β-cell function and T2D susceptibility.