Es-SOX8 regulates the morphological changes of the sperm nucleus of Eriocheir sinensis by activating Es-BMP2 transcription

The SRY-related high mobility group(HMG)box(SOX)transcription factors participate in many physiological processes of animal growth,development,and reproduction and are related to spermatogenesis in many species.However,the relationship between SOX and spermatogenesis in Eriocheir sinensis is rarely reported.Here,we studied the role of Es-SOX8 in the spermatogenesis of E.sinensis and its possible regulation mechanism.Immunofluorescence results demonstrated Es-SOX8 signal in both cytoplasm and nucleus of spermatogonia,spermatocytes as well as spermatids,but not in mature spermatozoa.Hematoxylin and eosin staining showed a significant increase in the number of spermatozoa with abnormal nuclear morphology in vivo,described as prominent edges and corners,after the knockdown of Es-SOX8 through RNA interference.This indicated a possible role of Es-SOX8 in the nuclear deformation process in the spermatogenesis of E.sinensis.Analysis of the mRNA levels of Es-bone morphogenetic protein 2(BMP2)in the Es-Sox8 knocked-down testis tissue revealed significantly decreased transcription of Es-BMP2.Chromatin immunoprecipitation results showed the binding of Es-SOX8 protein to the promoter region of Es-BMP2.Thus,Es-SOX8 can directly regulate the transcription of Es-BMP2 by activating the promoter of Es-BMP2 and thus affects the sperm nucleus deformation of E.sinensis.

Mitochondria: transportation, distribution and function during spermiogenesis

Spermiogenesis is a dynamic process which includes organelle reorganization and new structure formation. The morphology and distribution of the mitochondria in germ cells change to accommodate the cellular requirement. Multiple molecular motors and related proteins participate in carrying and anchoring mitochondria to the midpiece during spermiogenesis and this process is regulated precisely. Energetic metabolism provides energy for cellular activity and influences sperm survival and motility directly. Ubiquitination of mitochondria takes place during spermiogenesis, which has been implicated in sperm quality control and mitochondrial inheritance. In light of the essential roles of mitochondria in energy production, calcium homeostasis and apoptosis, mitochondria dysfunction cause severe human diseases, such as male infertility. The present study paves a way for a more detailed exploration of the biology of mitochondria during spermiogenesis.

Es-ATG7 is required for spermatogenesis of Eriocheir sinensis and modulates p53-dependent apoptosis in germ cells

Spermatogenesis is a complicated and highly regulated male gamete differentiation process that begins with the proliferation and differentiation of spermatogonia to the release of the mature spermatozoa.The autophagy-related gene atg7 has been reported as closely related to spermatogenesis and communication of Sertoli cell-germ cells in mice,including acrosome biogenesis,sperm flagellum development,and ectoplasmic specialization assembly.However,the function of es-ATG7 and its molecular regulatory mechanism during spermatogenesis in Crustacea remain largely unknown.Here,we cloned and identified es-atg7 from the testes of the Chinese mitten crabs Eriocheir sinensis and found that the expression of es-atg7 was relatively high in testes through semi-quantitative RT-PCR.The dynamic localization of es-ATG7 detected by immunofluorescence may convey information about its role in the spermatogenesis of E.sinensis.Furthermore,a knockdown of es-atg7 revealed that the malformed sperm with irregular sperm shape or loose nuclear cup and germ cell apoptosis were increased significantly.Accompanying this,we found an up-regulated expression of es-p53 during spermatogenesis in es-atg7 knockdown groups.Altogether,our results indicate that es-ATG7 plays an essential role during spermatogenesis of E.sinensis,and we demonstrated that es-ATG7 acts as an antagonist for p53-dependent apoptosis induction in this process.

KIFC1 overexpression promotes prostate cancer cell survival and proliferation in vitro by clustering of amplified centrosomes via interaction with Centrin 2

Mitotic kinesin KIFC1 plays critical roles in mitosis by regulating the spindle length,pole formation,and known for clustering extra centrosomes in cancer cells.Centrosome clustering is associated with the survival of cancer cells,but this phenomenon remains obscure in prostate cancer(PCa).The present study demonstrated that PCa cells showed centrosome amplification and clustering during interphase and mitosis,respectively.KIFC1 is highly expressed in PCa cells and tumor tissues of prostatic adenocarcinoma(PAC)patients.Up-regulation of KIFC1 facilitated the PCa cell survival in vitro by ensuring bipolar mitosis through clustering the multiple centrosomes,suggesting centrosome clustering could be a leading cause of prostate carcinogenesis.Conversely,the silencing of KIFC1 resulted in normal centrosome number or multipolar mitosis by inhibiting the clustering of amplified centrosomes in PCa cells.Besides,knockdown of KIFC1 by RNAi in PCa cells reduced cancer cell survival,and proliferation.KIFC1 interacted with centrosome structural protein Centrin 2 in clustering of amplified centrosomes in PCa cells to ensure the bipolar mitotic spindle formation.Knockdown of Centrin 2 in PCa cells inhibited the centrosome amplification and clustering.Moreover,up-regulated KIFC1 promotes PCa cell proliferation via progression of cell cycle possibly through aberrant activation of cyclin dependent kinase 1(Cdk1).Therefore,KIFC1 can be a prognostic marker and therapeutic target of PCa for inhibiting the cancer cell proliferation.