Ionizing radiation induced transcriptional changes in the developing mouse brain

Brain damage induced by prenatal irradiation is of major concern in radioprotection. The brain is the final result of a series of well timed consecutive or concomitant waves of cellular proliferation, migration, and differentiation. Acute irradiation during pregnancy could selectively disturb these events to result in various forms of malformation such as microcephaly, reduced cortical thickness and mental retardation. In this work we focus on the transcriptional alterations induced by ionizing radiation in the mouse developing brain. In conclusion this study encompasses the ionizing radiation response in the developing brain, with emphasis on transcriptional modulations. In a first part, the study answers on the question that concerns the different genes modulated in the irradiated embryonic brain, and the importance of P53 in this response. Further analysis indicates that ionizing radiation shows its strongest transcriptional response in the embryonic cerebral cortex. In depth screening of the cellular and molecular responses to low dose ionizing radiation in the main cell-types of the developing brain, exhibit a distinct variation in the way they response to the provoked oxidative stress. Finally, we demonstrate that radiation induced impairement of neural differentiation may contribute to an incorrect formation of the neural network.