Males carrying one copy of αTub85EβTub85D.PH in a wild-type background are fertile.
Four copies causes some spermatids to be misaligned, a lower copy number does not affect spermatid alignment. The ultrastructure of the axoneme is defective: expression causes defects in morphogenesis of the central pair and accessory microtubules. Expression does not affect the spindles or other classes of cytoplasmic microtubules.
αTub85EβTub85D.PH, βTub85D432 has male sterile phenotype
Males carrying one copy of αTub85EβTub85D.PH and one copy of βTub85D432 in an otherwise wild-type background are sterile.
Transheteroallelic combinations of αTub84B produces males that are sterile or weakly fertile. Expression of αTub85EβTub85D.PH partially rescues the defective αTub84B function in spermatogenesis: most spermatids have complete axonemes.