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As a key mediator of the transforming growth factor-beta (TGF-β) signaling pathway, which plays a pivotal role in regulating mammalian reproductive performance, Sma- and Mad-related protein 4 (SMAD4) is closely associated with the development of ovarian follicular. However, current knowledge of the genome-wide view on the role of SMAD4 gene in mammalian follicular granulosa cells (GCs) is still largely unknown. In the present study, RNA-Seq was performed to investigate the effects of SMAD4 knockdown by RNA interference (SMAD4-siRNA) in porcine follicular GCs. A total of 1025 differentially expressed genes (DEGs), including 530 upregulated genes and 495 downregulated genes, were identified in SMAD4-siRNA treated GCs compared with that treated with NC-siRNA. Furthermore, functional enrichment analysis indicated that upregulated DEGs in SMAD4-siRNA treated cells were mainly enriched in cell-cycle related processes, interferon signaling pathway, and immune system process, while downregulated DEGs in SMAD4-siRNA treated cells were mainly involved in extracellular matrix organization/disassembly, pathogenesis, and cell adhesion. In particular, cell cycle and TGF-β signaling pathway were discovered as the canonical pathways changed under SMAD4-silencing. Taken together, our data reveals SMAD4 knockdown alters the expression of numerous genes involved in key biological processes of the development of follicular GCs and provides a novel global clue of the role of SMAD4 gene in porcine follicular GCs, thus improving our understanding of regulatory mechanisms of SMAD4 gene in follicular development.

Asthenozoospermia is one of the leading causes of male infertility owing to a decline in sperm motility. Herein, we determined if there is a correlation between RNASET2 content on human spermatozoa and sperm motility in 205 semen samples from both asthenozoospermia patients and normozoospermia individuals. RNASET2 content was higher in sperm from asthenozoospermia patients than in normozoospermia individuals. On the other hand, its content was inversely correlated with sperm motility as well as progressive motility. Moreover, the inhibitory effect of RNASET2 on sperm motility was induced by incubating normozoospermic sperm with RNase T2 protein. Such treatment caused significant declines in intracellular spermatozoa PKA activity, PI3K activity and calcium level, which resulted in severely impaired sperm motility, and the sperm motility was largely rescued by cAMP supplementation. Finally, protein immunoprecipitation and mass spectrometry identified proteins whose interactions with RNASET2 were associated with declines in human spermatozoa motility. AKAP4, a protein regulating PKA activity, coimmunoprecipated with RNASET2 and they colocalized with one another in the sperm tail, which might contribute to reduced sperm motility. Thus, RNASET2 may be a novel biomarker of asthenozoospermia. Increases in RNASET2 can interact with AKAP4 in human sperm tail and subsequently reduce sperm motility by suppressing PKA/PI3K/calcium signaling pathways.

Coactivator-associated arginine methyltransferase 1 (CARM1) is a type I arginine methyltransferase that methylates the arginine residues of histone and nonhistone. Carm1 regulates various cellular processes, including transcriptional regulation, mRNA processing, cellular proliferation, and differentiation. Blastomeres with high Carm1 expression levels show cleavage tendency to inner cell mass (ICM) in mouse embryos. However, details about the factors for CARM1 distribution in mouse early embryos and the role of Carm1 in blastocyst development remain unclear. Here, the endonuclear distribution of CARM1 protein was heterogeneous between blastomeres from the late four-cell stage to the blastocyst stage. The heterogeneity of CARM1 distribution in blastomeres at the late four-cell stage was randomly obtained from two-cell stage embryos. From the four-cell stage to morula, CARM1 in individual blastomere remained heterogeneous. In the blastocyst stage, CARM1 protein level in ICM was much higher than that in trophoblast. We found that microRNA (miRNA) miR-181a is an important regulator for Carm1 distribution at the late four-cell stage. The ratio of heterogeneous embryos was reduced in all the embryos when miR-181a was inhibited. CARM1 inhibition reduced the level of symmetrical histone H3 arginine-26 dimethylation and impaired blastocyst development. Silencing Carm1 reduced cell number and increased cell apoptosis at the blastocyst stage. These results show a CARM1 heterogeneous distribution from the four-cell embryos to the blastocysts. miR-181a regulates the control of CARM1 heterogeneous distribution in the four-cell-stage embryos, and CARM1 is an important protein in regulating blastocyst development.

The invasion of maternal decidua by extravillous trophoblast (EVT) is essential for the establishment and maintenance of pregnancy, and abnormal trophoblast invasion could lead to placenta-associated pathologies including early pregnancy loss and preeclampsia. SEC5, a component of the exocyst complex, plays important roles in cell survival and migration, but its role in early pregnancy has not been reported. Thus, the present study was performed to explore the functions of SEC5 in trophoblast cells. The results showed that SEC5 expression in human placental villi at first trimester was significantly higher than it was at the third trimester, and it was abundantly localized in the cytotrophoblast (CTB) and the trophoblastic column. SEC5 knockdown was accompanied by reduced migration and invasion in HTR-8/SVneo cells. In addition, the expression and plasma membrane distribution of integrin β1 was also decreased. Furthermore, shRNA-mediated knockdown of SEC5 inhibited the outgrowth of first trimester placental explants. SEC5 and InsP₃R were colocalized in the cytoplasm of HTR-8/SVneo cells, and the cell-permeant calcium chelator BAPTA-AM could significantly inhibit HTR-8/SVneo cell invasion. The Ca²⁺ imaging results showed that the 10% fetal bovine serum-stimulated cytosolic calcium concentration ([Ca²⁺]c) was not only reduced by downregulated SEC5 but also was blocked by the InsP₃R inhibitor. Furthermore, either the [Ca²⁺]c was buffered by BAPTA-AM or the knockdown of SEC5 disrupted HTR-8/SVneo cell F-actin stress fibers and caused cytoskeleton derangement. Taken together, our results suggest that SEC5 might be involved in regulating trophoblast cell migration and invasion through the integrin/Ca²⁺ signal pathway to induce cytoskeletal rearrangement.

Summary. The concentrations of LH, FSH, prolactin, oestradiol and progesterone in serum were measured daily during the menstrual cycle of 100 normal Chinese women. The cyclic changes in LH, FSH, oestradiol and progesterone were typical of ovulatory cycles in women of other ethnic groups as reported in the literature. The geometric mean of the LH midcycle peak value was 51·64 i.u./l, the FSH mid-cycle peak value was 11 ·52 i.u./l, the preovulatory oestradiol peak was 1229·12 pmol/1, and the progesterone luteal maximum was 53·27 nmol/1. The cyclic changes of prolactin concentrations were irregular: the value at mid-cycle was significantly higher than that at the follicular or luteal phases.

A correlation between the length of the cycle and mean concentrations of LH and oestradiol at different stages throughout the cycle was shown.

Cullin 3 (CUL3), a scaffold protein, assembles a large number of ubiquitin ligase complexes, similar to Skp1-Cullin 1-F-box protein complex. Several genetic models have shown that CUL3 is crucial for early embryonic development. Nevertheless, the role of CUL3 in human trophoblast function remains unclear. In this study, immunostaining revealed that CUL3 was strongly expressed in the villous cytotrophoblasts, the trophoblast column, and the invasive extravillous trophoblasts. Silencing CUL3 significantly inhibited the outgrowth of villous explant ex vivo and decreased invasion and migration of trophoblast HTR8/SVneo cells. Furthermore, CUL3 siRNA decreased pro-MMP9 activity and increased the levels of TIMP1 and 2. We also found that the level of CUL3 in the placental villi from pre-eclamptic patients was significantly lower as compared to that from their gestational age-matched controls. Moreover, in the lentiviral-mediated placenta-specific CUL3 knockdown mice, lack of CUL3 resulted in less invasive trophoblast cells in the maternal decidua. Taken together, these results suggest an essential role for CUL3 in the invasion and migration of trophoblast cells, and dysregulation of its expression may be associated with the onset of pre-eclampsia.