Functional Analysis Of Mouse Spermatogenesis-related Genes

Mammalian Spermatogenesis is a unique cell differentiation process and can be divided into three stages: mitosis, meiosis, and spermiogenesis. Primitive type A spermatogonia differentiate to form primary spermatocytes. The primary spermatocytes enter first meiosis after DNA replication for last time and give rise to two secondary spermatocytes, which then undergo second meiosis without DNA replication and form haploid round spermatids. Subsequently, these cells enter spermiogenesis and undergo histone-protamine replacement reaction, nuclear condensation, and major morphological changes to form completed spermatozoa. These serial processes for forming male gametes are basically controlled by the programmed expression of a number of stage-specific genes. However, many aspects of the mechanisms of spermatogenesis have remained elusive because of a lack of suitable in vitro or in vivo models. In present study, we have tried to investigate functions of genes related to spermatogenesis by using testicular transplantation, Western Blot, RNAi technology and Co-IP, in order to further understand the molecular mechanisms of spermatogenesis. The present study includes three parts.1, Spermatogenesis Following Syngeneic Testicular Transplantation in Balb/c Mice Theobjective of this study was to examine the development of grafted testes and the kinetics of spermatogenesis following syngeneic testicular transplantation in both male and female recipient Balb/c mice in an effort to establish an in vivo culture system and to compare the effects of host sex on spermatogenesis. The testes from 5-day-old Balb/c mice were transplanted under the dorsal skin of four-week-old mice. Twenty male and twenty female Balb/c mice were used as the hosts and each host received 4 grafts. The recipient mice were killed at 1, 2, 3, 5, 7, 9, 12 and 15 weeks after transplantation. The graft survival rate and graft size were measured. The status of spermatogenesis was assessed by histological analyses. The expression of the spermatid-specific Protamine-2 gene was examined by RT-PCR. Overall, 70.3% of the testicular grafts in male hosts and 67.2% in female hosts survived. All recover(?)...