Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore.
Radiat Res. 2022 Mar 1;197(3):261-269. doi: 10.1667/RADE-21-00145.1.
Metaphase-based cytogenetic methods based on scoring of chromosome aberrations for the estimation of the radiation dose received provide a powerful approach for evaluating the associated risk upon radiation exposure and form the bulk of our current knowledge of radiation-induced chromosome damages. They mainly rely on inducing quiescent peripheral lymphocytes into proliferation and blocking them at metaphases to quantify the damages at the chromosome level. However, human organs and tissues demonstrate various sensitivity towards radiation and within them, self-proliferating progenitor/stem cells are believed to be the most sensitive populations. The radiation-induced chromosome aberrations in these cells remain largely unknown, especially in the context of an intact living organism. Zebrafish is an ideal animal model for research into this aspect due to their small size and the large quantities of progenitor cells present during the embryonic stages. In this study, we employ a novel metaphase-based cytogenetic approach on zebrafish embryos and demonstrate that chromosome-type and chromatid-type aberrations could be identified in progenitor cells at different cell-cycle stages at the point of radiation exposure. Our work positions zebrafish at the forefront as a useful animal model for studying radiation-induced chromosome structural changes in vivo.
基于中期的细胞遗传学方法通过对染色体畸变的评分来估计所接受的辐射剂量，为评估辐射暴露相关风险提供了有力的方法，并构成了我们目前对辐射诱导染色体损伤的大部分认识。这些方法主要依赖于诱导静止的外周淋巴细胞增殖并将其阻断在中期，以量化染色体水平的损伤。然而，人体器官和组织对辐射表现出不同的敏感性，在这些组织中，自我增殖的祖细胞/干细胞被认为是最敏感的群体。这些细胞中的辐射诱导染色体畸变在很大程度上是未知的，特别是在完整的活体生物中。斑马鱼是研究这方面的理想动物模型，因为它们体型小，在胚胎阶段存在大量的祖细胞。在这项研究中，我们在斑马鱼胚胎上采用了一种新颖的基于中期的细胞遗传学方法，证明在辐射暴露时，可以在不同细胞周期阶段的祖细胞中识别出染色体型和染色单体型畸变。我们的工作使斑马鱼成为研究体内辐射诱导染色体结构变化的有用动物模型的前沿。
