Whole genome RNA-interference screen for novel regulators of the insulin promoter

描述（由申请人提供）：本申请涉及广泛的挑战领域11：再生和特定主题挑战主题11- dk -105：一种细胞命运的转分化或定向重编程（例如，胰腺外分泌细胞到胰腺β细胞）。2005年，美国糖尿病前期/糖尿病的发病率接近40%，预计这一数字还会上升。目前的治疗方法是不够的：我们不能防止II型糖尿病患者的β细胞死亡，而且只有很少一部分I型糖尿病患者可以进行胰腺移植。因此，再生或保存胰腺细胞的能力将产生巨大的临床影响。对胰岛素启动子的研究导致了这种新的治疗方法。在小鼠中，激活胰岛素启动子的3种转录因子的异位表达可将胰腺外分泌细胞转化为产生胰岛素的内分泌细胞。这些有趣的发现表明，β细胞分化程序可以用于治疗用途，而胰岛素启动子是该程序的必要组成部分。我们建议通过全基因组RNA干扰（RNAi）筛选胰腺β细胞中胰岛素启动子的调节因子来发现这些新的β细胞再生和保存靶点。我们已经开发了一种统计上可靠的、高通量的胰岛素启动子活性RNAi筛选系统，并且已经开始识别新的靶点。我们将用β细胞转录组的深度测序来补充这个功能数据集。最后，我们将使用转基因RNAi小鼠在体内确认我们的成功。这一合作提议将RNA干扰实验室的专业知识和紧邻的细胞生物学实验室的专业知识结合在一起。在资助期结束时，我们预计至少会发现几个新的胰岛素启动子调节因子，这不仅会提高我们对β细胞生物学的理解，而且还将作为糖尿病治疗的新药物靶点。

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area 11: Regeneration and specific topic challenge topic 11-DK-105: Transdifferentiation or directed reprogramming of one cell fate to another (e.g., a pancreatic exocrine cell to a pancreatic beta cell). In 2005, rates of pre-diabetes/diabetes approached 40% in the US and this number is projected to rise. Current therapies are inadequate: we cannot prevent the death of beta cells in type II diabetics and pancreas transplant is available to very little type I diabetics. Therefore, the ability to regenerate or preserve the pancreatic beta cell would make an immense clinical impact. The study of the insulin promoter has led to such novel therapies. In mice, the ectopic expression of 3 transcription factors that activate the insulin promoter can convert pancreatic exocrine cells into insulin producing endocrine cells. These intriguing findings show that a program of beta cell differentiation can be co-opted for therapeutic use and that the insulin promoter is a necessary part of this program. We propose to find these new targets for beta cell regeneration and preservation by performing whole genome RNA interference (RNAi) screen for regulators of the insulin promoter in pancreatic beta cells. We have developed a statistically robust, high throughput RNAi screening system for insulin promoter activity and have already begun to identify novel hits. We will complement this functional data set with deep sequencing of the beta cell transcriptome. Finally, we will confirm our hits in vivo using transgenic RNAi mice. This collaborative proposal brings together the resources of a lab with expertise in RNA interference and an immediately adjacent lab with expertise in beta cell biology. At the end of the grant period, we anticipate the identification of at least several novel insulin promoter regulators that will not only heighten our understanding of beta cell biology but will also serve as novel drug targets for diabetes treatment. PUBLIC HEALTH RELEVANCE: In 2005, nearly 40% of the US population had diabetes or pre-diabetes - diseases caused by insulin deficiency. We propose to identify genes that regulate insulin production by the pancreatic beta cell. We hope that these genes could be targets for new diabetes therapies.