DNA PK IN RADIATION DAMAGE REPAIR AND LYMPHOMAGENESIS

辐射损伤修复和淋巴生成中的 DNA PK

• 批准号: 6513284
• 负责人: GLORIA C LI
• 金额: $ 27.13万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6513284
• 关键词: DNA damage; DNA repair; cell growth regulation; chromosome aberrations; enzyme complex; enzyme mechanism; gel electrophoresis; gene rearrangement; gene targeting; genetic crossing over; genetic recombination; genetically modified animals; immunogenetics; ionizing radiation; laboratory mouse; lymphocyte; lymphoma; neoplastic transformation; protein kinase; radiation carcinogenesis; radiation genetics; radiation related neoplasm /cancer; radiation sensitivity; tumor suppressor genes

DESCRIPTION: DNA-dependent protein kinase DNA-PK is a serine-threonine kinase that consists of a 465-kDA catalytic subunit, DNA-PKcs, and a 70 kDA and an 86-kDa heterodimeric DNA-targeting component, Ku70 and Ku80. Based on our recent pilot studies of Ku70- /- and Ku80-/- mice and earlier studies of SCID mice by others, it is postulated that each of the three components of DNA-PK may have distinct yet overlapping roles. The proposed studies aim at a test of this hypothesis and the elucidation of the physiological roles of the individual components of DNA-PK in DNA double- strand break (DSB) repair and V(D)J recombination, in lymphocyte development and lymphomagenesis. There are two specific aims. Specific Aim 1 focuses on the physiological role(s) of the individual subunits in DSB repair, V(D)J recombination and lymphocyte development. We plan to generate mutant mice and cell lines deficient in one or more of these polypeptides, and use them to deduce the roles of individual components of DNA-PK during T-and B-cell development, and in the repair of radiation-induced DSB and the associated effects on radiation sensitivity. In addition, we will examine the effect of low (non-lethal) does of ionizing radiation on V(D)J recombination in these mutant mice and evaluate whether T- and B-cell development can be restored by X- irradiation and whether such restoration enhances the development of lymphoma. Specific Aim II focuses on the role(s) of Ku70, Ku80 and DNA-PKcs in lymphomagenesis and tumorigenesis. We will test a hypothesis, inferred from our preliminary studies, that the loss of Ku70 enhances illegitimate recombination and leads to the development of lymphoma. Using various mutant mice and cell lines, spontaneous tumor development and tumor induction by ionizing radiation will be studied in vivo, and neoplastic transformation in vitro. In addition, the induction of chromosome damage (chromosome aberrations and sister chromatid exchanges) with and without X-irradiation will be examined with a view to understand the roles of the individual subunits of DNA-PK in the maintenance of genomic stability. The proposed study should add new information and insight regarding the physiological functions of DNA-PK and its individual subunits in programmed gene rearrangement and the maintenance of genomic stability. Furthermore, our studies should verify whether there is a role of Ku70 in lymphomagenesis, and specifically whether Ku70 may be considered as a candidate tumor suppressor gene.

描述：DNA依赖性蛋白激酶DNA-PK是丝氨酸 - 硫酸 由465 kDa催化亚基，DNA-PKC和70组成的激酶 KDA和86 kDa异二聚体DNA靶向组件KU70和KU80。 根据我们最近对Ku70- / - 和Ku80 - / - 小鼠以及更早的试点研究 其他人对SCID小鼠的研究，据推测，这三者中的每一个 DNA-PK的组件可能具有不同但重叠的角色。提议 研究旨在检验这一假设和阐明 DNA-PK单个成分在DNA双 - Strand Break（DSB）修复和V（D）J重组，在淋巴细胞中 发育和淋巴作用。有两个具体的目标。 特定目标1着重于个体的生理作用 DSB修复中的亚基V（d）J重组和淋巴细胞发育。我们 计划生成一个或多个缺陷的突变小鼠和细胞系 这些多肽，并用它们推断个人的角色 T-and B细胞发育过程中的DNA-PK的组件，并修复 辐射引起的DSB以及对辐射灵敏度的相关影响。 此外，我们将研究低（非致命）的影响 这些突变小鼠的V（d）J重组的电离辐射和 评估X-是否可以恢复T-和B细胞的发展 辐照以及这种恢复是否增强了 淋巴瘤。 特定的AIM II着重于KU70，KU80和DNA-PKC的作用 淋巴作用和肿瘤发生。我们将检验一个假设，推断 从我们的初步研究中，KU70的损失增强了非法 重组并导致淋巴瘤的发展。使用各种 突变小鼠和细胞系，自发肿瘤发育和肿瘤 通过电离辐射诱导将在体内研究，肿瘤 体外转化。另外，染色体损伤的诱导 （染色体畸变和姐妹染色单体交换） X-radiation将进行检查，以了解 DNA-PK的各个亚基在维持基因组稳定性方面。 拟议的研究应添加有关 DNA-PK的生理功能及其单个亚基 编程的基因重排和基因组稳定性的维持。 此外，我们的研究应验证Ku70是否在 淋巴作用，特别是Ku70是否可以被视为 候选肿瘤抑制基因。