The Drosophila Homologue of Tubulin-Specific Chaperone E–Like Protein Is Required for Synchronous Sperm Individualization and Normal Male Fertility

The tubulin-specific chaperone E–like protein (TBCEL or E-like) of vertebrates shows sequence homology to TBCE, a component of the multimolecular complex required for tubulin heterodimer formation in all eukaryotic cells. TBCEL apparently serves more specific functions, as it is found only in animals. At the cellular level, TBCEL plays a role as a regulator of tubulin stability. It is strongly expressed in human testes, but its systemic function is not known. The gene CG12214 codes for the Drosophila homologue of the vertebrate TBCEL protein. Here we show that disruption of the Drosophila Tbcel gene causes defects in spermatid individualixation, which leads to dispersed migration of F-actin–rich investment cones. Mutations affecting the Tbcel gene cause strong reduction in male, but not female, fertility. However, mature sperm function apparently is not impaired. We generated polyclonal antisera against TBCEL to study its localization and distribution in Drosophila tissues. Immunostainings of wild-type an...