Cyclin-Dependant Kinase 2 (CDK2) Function in Pancreatic Beta-Cells

描述(申请人提供)：2型糖尿病包括β细胞质量减少和胰岛素分泌受损，但质量和分泌之间的关系尚不清楚。细胞周期蛋白依赖性激酶(CDK)调节细胞周期机制和β细胞的增殖，可能成为增加患者β细胞质量的新药靶点。然而，我们的新数据显示，在β细胞质量发生变化之前很久，阻断CDK2信号就会意外地扰乱β细胞的功能，这表明CDK2可能是β细胞增殖和分泌功能的整合因子。我们假设CDK2通过与离子通道、胰岛素受体信号通路和β细胞的燃料代谢相互作用来影响β细胞的功能。我们将利用β细胞中CDK2缺失的小鼠模型，使用新型代谢传感器，结合膜片钳电生理和胰岛素分泌分析，(1)确定β细胞分泌途径中CDK2的靶点，(2)确定CDK2在控制β细胞生物能量学中的作用，以及(3)在人胰岛中建立CDK2途径，并测试CDK2表达是否拯救糖尿病人胰岛的β细胞功能。为了实现这些目标，我的导师Les Satin博士将为电生理学提供支持，我的共同导师Rane博士和合作者Beral-Mizrachi博士将提供使用更先进的糖尿病模型的培训。布雷姆糖尿病中心的协作环境将提供对试剂和专业知识的访问，这些试剂和专业知识将支持这项工作，并使创建其他小鼠模型能够准确地删除CDK2。我们建议的获得资源和培训的机会将使我能够建立一条独立的研究路线，并将促进我的发展、生产力和独立性。此外，所获得的结果将对开发增加2型糖尿病患者β细胞质量和分泌功能的新疗法具有重要意义。

DESCRIPTION (provided by applicant):Type 2 diabetes involves reduced β-cell mass and impaired insulin secretion, but the relationship between mass and secretion is not well understood. Cyclin dependent kinases (Cdks) regulate cell cycle machinery and β-cell proliferation and could be possible targets for new drugs to increase β-cell mass in patients. Our new data, however, shows that interrupting Cdk2 signaling unexpectedly disrupts β-cell function long before changes in β-cell mass occur, suggesting Cdk2 might be an integrator of β-cell proliferation and secretory function. We hypothesize that Cdk2 affects β-cell function by interacting with ion channels, the insulin receptor signaling pathway, and β-cell fuel metabolism. We will take advantage of a mouse model lacking Cdk2 in its β-cells and use novel metabolic sensors combined with patch-clamp electrophysiology and insulin secretion assays to (1) determine the targets of Cdk2 in the β-cell secretory pathway, (2) determine the role of Cdk2 in controlling β-cell bioenergetics, and (3) establish the Cdk2 pathway in human islets and test whether Cdk2 expression rescues β-cell function in diabetic human islets. To accomplish these aims, my mentor, Dr. Les Satin, will provide support for the electrophysiology, and my co-mentor Dr. Rane and collaborator Dr. Bernal- Mizrachi will provide training in the use of more advanced diabetes models. The collaborative environment at the Brehm Diabetes Center will provide access to reagents and expertise that will support this work and enable the creation of other mouse models to acutely delete Cdk2. The access to resources and training we propose will allow me to establish an independent line of research and will promote my development, productivity, and independence. In addition, the results obtained will be important for the development of new treatments for increasing β-cell mass and secretory function in Type 2 diabetics.