RADIATION INDUCED GENOMIC INSTABILITY

细胞向癌变状态的进展通常是 与基因组完整性的丧失有关，表现为变量 基因组变化，即不稳定性。这项研究的目的是 提供对分子、遗传学、细胞遗传学和细胞学的见解 保持基因组完整性或促进基因组的过程 在电离辐射下存活的细胞的不稳定性。 具体地说，这项研究直接调查了发端是否 事件位于核内或核外。染色体的不稳定性是 在含有人4号染色体的仓鼠-人杂交细胞中进行的研究 采用荧光原位杂交技术。的独特功能 微束允许用阿尔法粒子照射细胞 通过亚细胞隔间。对单个细胞进行成像， 用1、4、8或16个阿尔法粒子通过核辐射 质心的或通过细胞质的。细胞在培养中保持 用于20-30个细胞分裂作为单个克隆。从染色体上看 发现了细胞核和细胞质的异常亚克隆 辐射。DNA双链断裂很有可能是 不是基因组不稳定的最有效的启动者。

Cellular progression towards the cancerous state frequently is associated with the loss of genomic integrity, expressing as variable genomic changes i.e. instability. The purpose of this study is to provide insights into the molecular, genetic, cytogenetic and cellular processes that maintain genomic integrity or promote genomic instability in cells surviving exposure to ionizing radiation. Specifically this study investigates directly whether the originating event is located intra-or extranuclearly. Chromosomal instability is studied in hamster-human hybrid cells containing human chromosome 4 using fluorescence in situ hybridisation. The unique capabilities of the microbeam allow for the irradiation of cells with alpha-particles through subcellular compartments. Individual cells were imaged and irradiated with 1, 4, 8 , or 16 alpha particles through the nuclear centroid or through the cytoplasm .Cells were maintained in culture for 20-30 cellular divisions as individual clones. Chromosomally aberrant sub-clones were found for nuclear and cytoplasmic irradiations.It is highly probable that a DNA double strand break is not the most efficient initiator of genomic instability.