Mammalian Spermatogenesis
نویسندگان
چکیده
The formation of mature spermatozoa is one of the most essential functions in life. A concerted sequence of events is needed to proliferate, maintain and mature germ cells starting with spermatogonial stem cells and culminating in mature gametes. Apart from the genetic background, this process requires highly organized tissue in which the complex process of spermatogenesis is strongly regulated by hormonal interplay, differential gene expression and cell-cell communication. Although similar overall principles of spermatogenesis are found in all mammalian testes in a much conserved pattern, numerous species-specific features such as efficiency and seasonality determine differences between the various mammals. In this article, we focus on morphological principles as well as on endocrine regulation and action of selected genes. Furthermore we report on recent experiments addressing the fate and physiology of spermatogonial stem cells, testis biology and development of the germ line and the somatic part of the testis by germ line transplantation and in vitro approaches. _____________________________________________________________________________________________________________
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