Fig. 4. Wild-type function of A11^13hd in the male reproductive tract. (A) Sperm were present in the lumens of wild-type and A11^13hd/13hd D11^+/+ seminiferous tubules (arrows), but not in A11^-/- D11^+/+ testis. (B) The A11^13hd/13hd D11^+/+ ductus deferens showed a wild-type morphology, while A11^-/- D11^+/+ mutants showed a coiled configuration resulting from an anteriorization towards epidydimis (arrows). E, epididymis; T, testis; V, vas deferens.