Figure 4. UTX is required for the expression of ku80 following IR exposure in Drosophila.

(A) Schematic illustration of the gene structure of wild type utx and a utx mutant allele (utx^Δ95) generated via the imprecise excision of a P-element insertion. (B, C) Genomic PCR (B) and Western blot (C) analyses to verify the utx^Δ95 genotype. (B) An approximately 250-bp band is detected in adult flies with a utx^Δ95/Cyo genotype, but absent from the w¹¹¹⁸ genotype. For details, please see the Materials and Methods section. (C) An approximately 130-kDa band indicated by an arrow in w¹¹¹⁸ flies was not detected in the utx^Δ95/utx¹ third instar larvae. A non-specific band is indicated by an asterisk, and β-Tubulin (β-Tub) was used as a loading control. (D) qRT-PCR analysis of mRNA expression for the indicated genes before and after IR exposure in the w ¹¹¹⁸ and utx^Δ95/utx¹ third instar larvae. The relative expression levels are normalized to β-tubulin levels. Note that ku80 is the only gene that requires utx for its expression.