Transheterozygotes between the cei maternal-effect allele and the aurBhi1045 insertional allele are late embryonic lethal, and this lethality is rescued by the Tol2-EF1��-aurB transgene.

1Embryonic phenotype on day 5 p.f., classified as either wild-type (normal morphology and swim bladder inflation) or inviable (protruding mouth, edema in the yolk region, darkening of the brain and lack of swim bladder inflation).2Genotypic classes of the embryos, as determined by genotyping of individual embryos after phenotypic scoring on day 5 p.f.3The presence of rare viable ��escaper�� cei/aurBhi1045 embryos in cross 1 and cei/aurBhi1045 embryos with no transgene in cross 3 is attributed to residual wild-type zygotic function provided by the cei mutant allele (see text).4In cross 3, a subset of the phenotypically normal embryos (57/128) were genotyped. The genotypic classes percentage values corresponding to the ��wild-type�� phenotypic category have been extrapolated from this tested sample.