Role of the RNA-binding, polyC-binding proteins in pancreatic beta cells

RNA 结合、多聚 C 结合蛋白在胰腺 β 细胞中的作用

基本信息

批准号：
10186740
负责人：
DORIS A STOFFERS
金额：
$ 44.93万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-01 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10186740
关键词：
3&apos Untranslated Regions Ablation Address Apoptosis Architecture B-Lymphocytes Beta Cell Binding Binding Proteins Cell Survival Cells Complex Cytosine Data Development Diabetes Mellitus Endocrine Environment Failure Family Generations Genes Genetic Genetic Transcription Genetic Translation Genomic approach Glucagon Glucose Intolerance Homeostasis Human Immunoprecipitation Impairment Initiator Codon Intervention MEKs Mediating Metabolic stress Molecular Morphology Mus Non-Insulin-Dependent Diabetes Mellitus Oxidation-Reduction Oxidative Stress Pathway interactions Phenotype Phosphorylation Physiological Play Post-Translational Protein Processing Protein Family Proteomics RNA Binding RNA Helicase RNA-Binding Proteins Regulation Role Somatostatin Specificity Stress Structure of beta Cell of islet Testing Therapeutic Transcript Translational Regulation Translations Viral Vector Work biological adaptation to stress blood glucose regulation crosslink db/db mouse diabetes mellitus therapy endoplasmic reticulum stress experience experimental study genetic approach glucose tolerance glucose-regulated proteins in vivo insulin secretion insulin tolerance islet member new therapeutic target novel novel therapeutic intervention prevent promoter recruit response ribosome profiling small hairpin RNA

项目摘要

Insufficient secretion of insulin from pancreatic β cells underlies all forms of diabetes. In type 2 diabetes (T2D), β cell failure is caused at least in part by prolonged oxidative and ER stress, which leads to impaired insulin secretion, apoptosis, and loss of cell identity. Thus, elucidating the molecular mechanisms comprising the β cell stress response is central to the development of novel therapeutic strategies. Regulation of mRNA translation is a critical and highly conserved component of the cellular response to stress. β cells are particularly dependent on translational controls, yet the factors controlling translation in β cells are largely unexplored. By focusing on translational regulation, we have identified the polyC binding protein family of RNA binding proteins (RBPs) comprising PCBPs1-4 and hnRNPk as important players in the post-transcriptional regulatory landscape of pancreatic beta cells. We have elucidated a novel hnRNPK/JunD pathway in β cells that influences redox homeostasis and cell viability during metabolic stress. Further, we find that PCBPs 1 and 2 post-transcriptionally regulate Nkx2.2, likely promoting beta cell identity and repressing alternate endocrine cell fates. Importantly, fundamental aspects of our findings have been validated ex vivo in primary mouse islets from wild-type and db/db mice and in human islets. We hypothesize that reducing stress to maintain β cell identity and survival has great therapeutic potential and will comprehensively explore this pathway with the following specific aims: (1) To elucidate the in vivo roles exerted by PCBPs 1 and 2 in beta cells, (2) to determine how hnRNPk influences the translational landscape of beta cells during stress, and (3) to establish the relevance of the polyC binding protein family of RBPs to human islet beta cell identity, function and survival. While highly ambitious, these experiments are feasible given our experience and our institutional environment. The new understanding of the roles of this family of RBPs in pancreatic beta cells and the mechanisms by which they regulate insulin secretion and organismal glucose homeostasis will elucidate much needed new targets for the therapy of diabetes.

胰腺 β 细胞分泌胰岛素不足是所有类型糖尿病 (T2D) 的基础。 β细胞衰竭至少部分是由长期氧化和内质网应激引起的，这会导致胰岛素受损因此，阐明了β的分子机制。细胞应激反应是 mRNA 调节新治疗策略开发的核心。翻译是β细胞对应激反应的关键且高度保守的组成部分。特别依赖于翻译控制，但控制 β 细胞翻译的因素很大程度上是通过关注翻译调控，我们已经确定了 RNA 的多聚 C 结合蛋白家族。结合蛋白 (RBP) 包括 PCBPs1-4 和 hnRNPk，它们是转录后过程中的重要参与者我们阐明了 β 细胞中新的 hnRNPK/JunD 通路。此外，我们发现 PCBPs 1 和 PCBPs 会影响代谢应激期间的氧化还原稳态和细胞活力。 2 转录后调节 Nkx2.2，可能促进 β 细胞身份并抑制交替内分泌重要的是，我们的研究结果的基本方面已在原代小鼠中得到了离体验证。我们在野生型和 db/db 小鼠的胰岛以及人类胰岛中发现了减少压力以维持β的作用。细胞身份和存活具有巨大的治疗潜力，将与以下具体目标：(1) 阐明 PCBP 1 和 2 在 β 细胞中发挥的体内作用，(2) 确定 hnRNPk 在应激期间如何影响 β 细胞的翻译景观，以及 (3) 建立 RBP 的多聚 C 结合蛋白家族与人胰岛 β 细胞身份、功能和功能的相关性尽管雄心勃勃，但鉴于我们的经验和制度，这些实验是可能的。对 RBP 家族在胰腺 β 细胞和胰腺β细胞中的作用的新认识。它们调节胰岛素分泌和生物葡萄糖稳态的机制将阐明很多糖尿病治疗需要新的靶点。