Fig. 3.
Meiotic arrest in mid-late zygotene stage in GilzΔ/y mutant testes. Anti-SYCP3 (red), DMC1 (green) and γH2AX (blue) staining of chromosomal spread preparations from control (+/Y, A–D) and mutant (Δ/Y, E, F) P12 testes was used to analyze meiotic prophase I cells. Mutant spermatocytes progressed normally from preleptotene to late zygotene and early pachytene. They showed a distinct γH2AX signal from preleptotene to zygotene all over the nucleus, and in pachytene the expected signal was restricted to the sex body. This suggests that double strand breaks are formed normally. DMC1 (meiotic Rad51 homolog) is recruited to the axis in zygotene, suggesting that repair is initiated. Mutant spermatocytes also revealed a significantly higher amount of nuclei showing a complete set of unsynapsed chromosomes (US) or nuclei containing both, unsynapsed (arrows) and homogenously synapsed chromosomes (H+US). PL, preleptotene; L, leptotene; Z, zygotene; P, pachytene.