Figure 2. Female-specific lethality of double heterozygous lines.

(A) Schematic illustration of the two-component system containing one driver and one effector. This system used an embryonic Lsbnk promoter to drive the tetracycline transactivator (tTAo), as well as a sex-specific intron (Chtra) splicing cassette linked to a cell death gene Lshid^Ala2 lethal effector to achieve highly efficient female lethality early in the development of L. cuprina. Addition of tetracycline to the diet prevents activation of the Lshid^Ala2 gene. 8 homozygous DR2–6# (B) or DR2–7# (C) males were crossed with 8 virgin females from homozygous effector lines and their offspring were raised on diet without tetracycline. The number of adult male and female offspring from each cross were counted. Error bars show the standard error of the mean (n = 3).