The Role of Oxidative Phosphorylation Complexes in Beta Cell Biology

项目摘要 分泌胰岛素的胰腺β细胞是一种高度代谢的细胞类型，其功能障碍是导致胰腺炎的主要原因。 糖尿病发病机制β细胞依赖于线粒体功能和葡萄糖的能量产生- 刺激胰岛素分泌。线粒体ATP的产生是由线粒体ATP酶的5个多亚基复合体完成的。 氧化磷酸化（oxidative phosphorylation，OXPHOS）系统。β细胞胞浆中ATP：ADP比例的增加是细胞内ATP含量的增加。 胰岛素释放的触发信号。虽然ATP产量的净减少会对β产生影响， 细胞功能和胰岛素分泌，单个OXPHOS复合物缺陷对β细胞生物学的影响， 功能仍然未知。事实上，有一个广泛的人类疾病所造成的缺陷， 个别OXPHOS复合物，从神经变性到心肌病，包括母体- 遗传性糖尿病，表明下游病理机制的多样性。因此，这一目标 一个建议是阐明三个单独的OXPHOS复合物（复合物I，III和IV）在上下文中的影响 胰岛β细胞的功能假设是，个别OXPHOS复合物中的缺陷将导致不同的 信号通路的改变会改变β细胞的生物学。根据初步数据，还假设， 复合物III缺陷型胰岛由于反应性糖蛋白的产生增加而发展为严重的高血糖表型。 氧物种和氧化应激。本建议书和培训计划将为申请人提供一个优秀的 培训环境与两个公认的专家在胰岛生理学和线粒体疾病作为共同导师。 作为两个实验室之间的合作，将使申请人有充分的机会扩大她的专业知识。 了解新的研究领域，学习新的科学模型和技术技能，增强批判性思维 和严格的实验设计，并为将研究问题转化为人类胰腺癌奠定了基础。 样品

Project Summary The insulin-secreting pancreatic beta cell is a highly metabolic cell type and its dysfunction is a main cause of diabetes pathogenesis. The beta cell is reliant on mitochondrial function and energy production for glucose- stimulated insulin secretion. Mitochondrial ATP production is accomplished by 5 multi-subunit complexes of the oxidative phosphorylation (OXPHOS) system. The increase in the ATP:ADP ratio in the beta cell cytosol is the triggering signal for insulin release. Although a net decrease in ATP production would have an impact on beta cell function and insulin secretion, the impact of individual OXPHOS complex defects on beta cell biology and function remains unknown. Indeed, there are a broad spectrum of human diseases caused by defects in individual OXPHOS complexes ranging from neurodegeneration to cardiomyopathies, including maternally- inherited diabetes, suggesting a diverse range of downstream pathomechanisms. Therefore, the objective of this proposal is to elucidate the impact of three individual OXPHOS complexes (Complex I, III, and IV) in the context of the pancreatic beta cell. The hypothesis is that defects in individual OXPHOS complexes will result in distinct signaling pathway changes that will alter beta cell biology. Based on preliminary data, it is also hypothesized that Complex III deficient islets develop a severe hyperglycemic phenotype due to increased production of reactive oxygen species and oxidative stress. This proposal and training plan will provide the applicant with an excellent training environment with two recognized experts in islet physiology and mitochondrial diseases as co-mentors. Being a collaboration between two laboratories will allow the applicant ample opportunities to broaden her knowledge of a new research area, learn new scientific models and technical skills, enhance her critical thinking and rigorous experimental design, and set the stage to translate research questions to human pancreatic samples.