Long-term effects of ionizing radiation on gene expression in a zebrafish model.

Long-term effects of ionizing radiation on gene expression in a zebrafish model.

Blog Article

Understanding how initial radiation injury translates into long-term effects is an important problem in radiation biology.Here, we define a set of changes in the transcription profile that are associated with the long-term response to radiation exposure.The study was performed in vivo using zebrafish, an established radiobiological model organism.

To study the long-term response, 24 hour post-fertilization embryos were exposed to 0.1 Gy (low dose) or 1.0 Gy (moderate dose) of whole-body gamma radiation and allowed to develop for 16 Baggies weeks.

Liver mRNA profiles were then analyzed using the Affymetrix microarray platform, with validation by quantitative PCR.As a basis for comparison, 16-week old adults were exposed at the same doses and analyzed after 4 hours.Statistical analysis was performed in a way to minimize the effects of multiple comparisons.

The responses to these two treatment regimes differed greatly: 360 probe sets were associated primarily with the long-term response, whereas a different 2062 probe sets were associated primarily with the response when adults of the Kids T-Shirt same age were irradiated 4 hours before exposure.Surprisingly, a ten-fold difference in radiation dose (0.1 versus 1.

0 Gy) had little effect.Analysis at the gene and pathway level indicated that the long-term response includes the induction of cytokine and inflammatory regulators and transcription and growth factors.The acute response includes the induction of p53 target genes and modulation of the hypoxia-induced transcription factor-C/EBP axis.

Results help define genes and pathways affected in the long-term, low and moderate dose radiation response and differentiate them from those affected in an acute response in the same tissue.