FIG. 2.

GAGA transgenes rescue viability of hemizygous Trl^13C flies. Viability was calculated as the percentage of the expected numbers based on Mendelian ratios. Numbers above bars indicate the total number of flies scored in a cross. (a) Siblings with (white columns) and without (black columns) a transgene were compared. Different bars of the same genotype represent different lines of a transgene. The viability of Trl^13C/Trl^R67 flies represents an average between two crosses involving different lines of the same transgene. All P values were smaller than 10⁻⁴, obtained by the χ² test. (b) Viability of Trl-null flies rescued by four copies of hsp83:GAGA-519, four copies of hsp83:GAGA-581, or two copies of each. Genotypes of flies examined were 4Xhsp83:GAGA-519; Trl^109.2/Trl^81.1 (Bar 1); 4Xhsp83:GAGA-581; Trl^109.2/Trl^R67 (Bar 2); 2Xhsp83:GAGA-581/2Xhsp83:GAGA-519; Trl^109.2/Trl^81.1 (Bar 3); 2Xhsp83:GAGA-581/2Xhsp83:GAGA-519; Trl^109.2/Trl^R67 (Bar 4). The rescue was significant in each case, with all P values smaller than 10⁻⁴ by Fisher's exact test.