FIG. 1.

HD and x-ray interactions at the gene level. Gene expression alterations were summarized across all nine treatment groups and a linear x-ray effect (open arrows) and an HD effect (black arrows) on co-exposure gene expression were determined. On top of a positive linear x-ray effect (A), a positive HD effect represents an agonistic effect on gene expression, whereas a negative HD effect is an antagonistic effect on gene expression. Similarly, on top of a negative linear x-ray effect (B), a positive HD effect is antagonistic, whereas a negative HD effect is agonistic.