Rsbp15KO males show spermatogenesis defects: testes are completely devoid of mature sperms in the seminal vesicle, but contain spermatocytes, round spermatids and elongated spermatids; the cystic bulge and waste bag structures are lost, and the individualization complex is asynchronous, as illustrated by individual cysts exhibiting both pre- and post-individualized spermatids; there is strong cell apoptosis signals in the tenth testis segment, indicating that the abnormal elongated spermatids undergo apoptosis before entering the seminal vesicle; in most cases, flagella show defects in central microtubules or/and outer microtubules in axonemes.
