RADIATION MUTAGENESIS OF HUMAN CELLS

人体细胞的辐射诱变

• 批准号: 2096775
• 负责人: ANDREW J. GROSOVSKY
• 金额: $ 16.36万
• 依托单位: UNIVERSITY OF CALIFORNIA RIVERSIDE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-02-01 至 1996-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2096775
• 关键词: DNA repair; X ray; alleles; ataxia telangiectasia; complementary DNA; diagnosis design /evaluation; disease /disorder proneness /risk; gene expression; gene mutation; genetic mapping; heterozygote; human genetic material tag; hypoxanthine phosphoribosyltransferase; ionizing radiation; lymphoblast; molecular cloning; molecular genetics; mutagens; mutant; nucleic acid sequence; polymerase chain reaction; radiation dosage; radiation sensitivity; restriction fragment length polymorphism; site directed mutagenesis; southern blotting; tissue /cell culture

The investigation outlined in this proposal is designed to improve our knowledge of critical parameters of radiation mutagenesis in human cells. The issues that we have selected for investigation, low dose effects, the influence of cellular repair proficiency, and potential differences among various genetic loci, have each been recognized for several decades but their role in radiation mutagenesis remains uncertain. Each of these critical parameters may substantially influence the observed mutational spectrum in a manner which cannot be accurately predicted at this time. Mutational spectra may be defined as the complete set of molecular events which can result in the expression of a mutant phenotype. This includes the distribution and PM of DNA sequence alterations which occur within a target locus. In addition, loss of heterozygosity (LOH) at previously heterozygous loci may occur by one of several possible mechanisms and account for a large fraction of all mutations occurring at such loci. These events are also essential elements of a mutational spectrum since they are responsible for a large proportion of observed mutant phenotypes. This proposal is designed to use mutational spectra, as broadly defined here, to coordinately investigate the critical parameters outlined above. Our specific objectives include: 1) the definition of mutational spectra from very low dose x-ray exposure (10 cGy) in TK6 human lymphoblasts; 2) determination of mutational spectra in cell lines derived from radiosensitive Ataxia Telangiectasia patients and their heterozygous relatives; 3) determination of comparative mutational spectra at three endogenous loci available for study in TK6 human lymphoblasts. Mutants will be collected by parallel selections from the same irradiated populations. The objective of the research proposed in this application is to develop a better understanding of the cellular, molecular and dosage factors which determine the spectrum of mutations induced by x-rays in human B lymphoblastoid cell lines. Improved understanding of the influence of these factors in radiation mutagenesis of human cells will permit a better estimate of the risk to human populations from low dose radiation exposure.

该提案中概述的调查旨在改善我们的 人类细胞中辐射诱变的临界参数的知识。 我们选择进行调查的问题，低剂量影响， 细胞修复能力的影响，以及潜在的差异 各种遗传基因座，每个人都被认可了几十年，但是 它们在辐射诱变中的作用仍然不确定。 每个 关键参数可能会大大影响观察到的突变 目前无法准确预测的方式频谱。 突变光谱可以定义为完整的分子事件集 这可能导致突变表型的表达。 这包括 DNA序列改变的分布和PM发生在A内 目标基因座。 此外，先前的杂合性丧失（LOH） 杂合基因座可能通过几种可能的机制之一发生，并且 占该基因座的所有突变的很大一部分。 这些事件也是突变频谱的基本要素 他们负责大部分观察到的突变表型。 该建议旨在使用突变光谱，如广义上的定义 在这里，要协调研究上面概述的关键参数。 我们的具体目标包括：1）突变光谱的定义 来自TK6人淋巴细胞中非常低剂量的X射线暴露（10 CGY）； 2） 从衍生的细胞系中的突变光谱测定 放射敏感性共济失调患者及其杂合子 亲属; 3）确定三个比较突变光谱 内源性基因座可用于TK6人淋巴细胞。 突变体 将通过同一辐照的平行选择来收集 人群。 本应用程序提出的研究的目的是开发 更好地了解细胞，分子和剂量因子 确定X射线在人B中诱导的突变频谱 淋巴母细胞系。 改善了对影响的影响 这些因素中人类细胞的辐射诱变的因素将允许更好 低剂量辐射暴露对人类人群的风险估计。