Male flies overexpressing JhI-26^Scer\UAS.cLa in testes under the control of Scer\GAL4^nos.PU or Scer\GAL4^Act.PU, when mated with wild-type females generate eggs which a hatch rate significantly lower than in control flies. Eggs from JhI-26^Scer\UAS.cLa-expressing males mated with Wolbachia-infected females do not exhibit a decrease in hatch rate, indicating that the presence of Wolbachia has 'rescued' the JhI-26 overexpression phenotype.

Embryos from JhI-26^Scer\UAS.cLa-expressing males and wild-type females reach late embryogenesis and develop a cuticle before dying. However, these cuticles consistently display head defects, sch as defects in the cephalopharyngeal apparatus. Around 67% of embryos display missing abdominal segments, or an internalized telson.

Embryos from wild-type females mated with JhI-26^Scer\UAS.cLa-overexpressing males display numerous abnormalities, including asynchronous cleavage, unevenly distributed nuclei and different sizes of the nuclei. In individual embryos, three highly correlated major defects are observed. First, smaller and narrower metaphase spindles appear in the syncytial blastoderms, which are very similar to haploid metaphase spindles. Second, centrosomes often dissociate from mitotic spindles. Thirdly, the spindles exhibit a strange morphology with a regular couple of tubulin-containing particles in the middle of the divided chromosomes at telophase.

Like Wolbachia-infected males, JhI-26^Scer\UAS.cLa-expressing males (under the control of Scer\GAL4^nos.PU or Scer\GAL4^Act.PU) may inhibit the receptivity to remating in mated wild-type females.