Wnt signaling in testis development: Unnecessary or essential?

Testis development is a fundamental process in sexual development and reproduction. It is under the regulation of multiple factors. Wnt signaling pathway is a classical pathway, which plays an essential role during early development. From a traditional view, Wnt signaling serves as a key regulator of female reproductive system. However, its role in testis development is relatively controversial. This paper reviews Wnt signaling's part in the major events during testis development, including primordial germ cell specification, proliferation and migration, testis determination, spermatogenesis and somatic cell regulation, and summarizes Wnt signaling's impact on testis-related disorders. We evaluate the outcomes of current studies in the field and suggest future research directions.

Mitochondrial prohibitin and its ubiquitination during crayfish Procambarus clarkii spermiogenesis.

Prohibitin (PHB), an evolutionarily conserved mitochondrial membrane protein, is associated with spermatogenesis and sperm quality control in mammals. It is identified as a substrate of ubiquitin and thus may function via a mitochondrial ubiquitin-proteasome pathway. In this study, we examined the localization of PHB during spermiogenesis of the macrura crustacean Procambarus clarkii. We traced phb mRNA's temporal and spatial expression pattern in spermiogenesis, and found its localization highly coherent with acrosome formation and nuclear shaping, two key events during crustacean spermiogenesis. We further detected the associations of PHB with mitochondria and ubiquitin using immunofluorescent staining. PHB was co-localized with mitochondria through spermiogenesis. PHB as well as mitochondria were co-localized with ubiquitin from the late stage of spermiogenesis, and the co-signals reached their peak in the mature sperm. The results raise the hypothesis that PHB is likely to function in nuclear shaping and acrosome formation in the spermiogenesis of P. clarkii. In addition, it might possess a more profound role in mediating mitochondrial ubiquitination. For the first time this study uncovers the role of PHB in the spermiogenesis of macrura crustacean species.