Eukaryotic expression, Co-IP and MS identify BMPR-1B protein-protein interaction network.

BACKGROUND: BMPR-1B is part of the transforming growth factor ß super family and plays a pivotal role in ewe litter size. Functional loss of exon-8 mutations in the BMPR-1B gene (namely the FecB gene) can increase both the ewe ovulation rate and litter size. RESULTS: This study constructed a eukaryotic expression system, prepared a monoclonal antibody, and characterized BMPR-1B/FecB protein-protein interactions (PPIs). Using Co-immunoprecipitation coupled to mass spectrometry (Co-IP/MS), 23 proteins were identified that specifically interact with FecB in ovary extracts of ewes. Bioinformatics analysis of selected PPIs demonstrated that FecB associated with several other BMPs, primarily via signal transduction in the ovary. FecB and its associated interaction proteins enriched the reproduction process via BMP2 and BMP4 pathways. Signal transduction was identified via Smads proteins and TGF-beta signaling pathway by analyzing the biological processes and pathways. Moreover, other target proteins (GDF5, GDF9, RhoD, and HSP 10) that interact with FecB and that are related to ovulation and litter size in ewes were identified. CONCLUSIONS: In summary, this research identified a novel pathway and insight to explore the PPi network of BMPR-1B.

Eukaryotic expression, Co-IP and MS identify BMPR-1B protein-protein interaction network

BACKGROUND: BMPR-1B is part of the transforming growth factor ß super family and plays a pivotal role in ewe litter size. Functional loss of exon-8 mutations in the BMPR-1B gene (namely the FecB gene) can increase both the ewe ovulation rate and litter size. RESULTS: This study constructed a eukaryotic expression system, prepared a monoclonal antibody, and characterized BMPR-1B/FecB protein-protein interactions (PPIs). Using Co-immunoprecipitation coupled to mass spectrometry (Co-IP/MS), 23 proteins were identified that specifically interact with FecB in ovary extracts of ewes. Bioinformatics analysis of selected PPIs demonstrated that FecB associated with several other BMPs, primarily via signal transduction in the ovary. FecB and its associated interaction proteins enriched the reproduction process via BMP2 and BMP4 pathways. Signal transduction was identified via Smads proteins and TGF-beta signaling pathway by analyzing the biological processes and pathways. Moreover, other target proteins (GDF5, GDF9, RhoD, and HSP 10) that interact with FecB and that are related to ovulation and litter size in ewes were identified. CONCLUSIONS: In summary, this research identified a novel pathway and insight to explore the PPi network of BMPR-1B.

Prolonged use of alendronate alters the biology of cranial repair in estrogen-deficient rats' associated simultaneous immunohistochemical expression of TGF-ß1+, α-ER+, and BMPR1B.

OBJECTIVES: TGF-ß1 is a cytokine that may induce both osteoneogenesis through Runx-2 or fibrosis via the transcription of α-smooth muscle actin (α-SMA). Because it has been previously known that alendronate increases the level of TGF-ß1 and that under the usual condition of bone metabolism the estrogen may prevent the fibrotic effect of TGF-ß1, the aim of this study was to evaluate if alendronate alters the cellular differentiation process post calvarial surgery in estrogen-deficient specimens. MATERIALS AND METHODS: A transosseous defect that was 5 mm in diameter was created on the calvarium of each of 32 female rats with previous ovarian-salpingo-oophorectomy. All defects were treated with autografts, and 16 rats received the administration of 1 mg/kg of alendronate three times a week until euthanasia on the 15th and 60th day post surgery. Histomorphometric and immunohistochemical analyses of the expression of TGF-ß1, estrogen receptor alpha nuclear (α-ER), α-SMA, BMPR1B, and Runx-2 were performed, and ELISA was used to measure the level of estrogen. RESULTS: All animals demonstrated low levels of estrogen post ovarian-salpingo-oophorectomy. The histological results demonstrated larger bone matrix deposition in specimens treated with alendronate on the 15th day post surgery. The result was associated with a higher co-expression of TGF-ß1, BMPR1B, and Runx-2 when compared with the control group. In addition, on the 60th day post surgery, the increase of bone matrix deposition from 15th to 60th day was discrete in specimens treated with alendronate compared with the control group. This result coincided with the intense simultaneous expression of TGF-ß1, α-ER, and α-SMA, whereas the expression of BMPR1B and Runx-2 decreased. CONCLUSION: The prolonged administration of alendronate altered the cranial repair in ovarian-salpingo-oophorectomized specimens due to the simultaneous occurrence of low estrogen and the presence of TGF-ß1+/α-ER+ inducing the presence of α-SMA+, whereas BMPR1B and Runx-2 were suppressed. CLINICAL RELEVANCE: The prolonged administration of alendronate alters osteoneogenesis and induces an unusual microenvironment in the bone that seems to imitate the physiological tissue damage that culminates in the loss of the functional layer of endometrium.

New mutations in non-syndromic primary ovarian insufficiency patients identified via whole-exome sequencing.

STUDY QUESTION: Is it possible to identify new mutations potentially associated with non-syndromic primary ovarian insufficiency (POI) via whole-exome sequencing (WES)? SUMMARY ANSWER: WES is an efficient tool to study genetic causes of POI as we have identified new mutations, some of which lead to protein destablization potentially contributing to the disease etiology. WHAT IS KNOWN ALREADY: POI is a frequently occurring complex pathology leading to infertility. Mutations in only few candidate genes, mainly identified by Sanger sequencing, have been definitively related to the pathogenesis of the disease. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study performed on 69 women affected by POI. PARTICIPANTS/MATERIALS, SETTING, METHODS: WES and an innovative bioinformatics analysis were used on non-synonymous sequence variants in a subset of 420 selected POI candidate genes. Mutations in BMPR1B and GREM1 were modeled by using fragment molecular orbital analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Fifty-five coding variants in 49 genes potentially related to POI were identified in 33 out of 69 patients (48%). These genes participate in key biological processes in the ovary, such as meiosis, follicular development, granulosa cell differentiation/proliferation and ovulation. The presence of at least two mutations in distinct genes in 42% of the patients argued in favor of a polygenic nature of POI. LIMITATIONS, REASONS FOR CAUTION: It is possible that regulatory regions, not analyzed in the present study, carry further variants related to POI. WIDER IMPLICATIONS OF THE FINDINGS: WES and the in silico analyses presented here represent an efficient approach for mapping variants associated with POI etiology. Sequence variants presented here represents potential future genetic biomarkers. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Universidad del Rosario and Colciencias (Grants CS/CIGGUR-ABN062-2016 and 672-2014). Colciencias supported Liliana Catherine Patiño´s work (Fellowship: 617, 2013). The authors declare no conflict of interest.

SOCS1 favors the epithelial-mesenchymal transition in melanoma, promotes tumor progression and prevents antitumor immunity by PD-L1 expression.

Silencing of SOCS1 protein with shRNAi lentivirus (shR-SOCS1) led to partial reversion of the tumorigenic phenotype of B16F10-Nex2 melanoma cells. SOCS1 silencing inhibited cell migration and invasion as well as in vitro growth by cell cycle arrest at S phase with increased cell size and nuclei. Down-regulation of SOCS1 decreased the expression of epidermal growth factor receptor, Ins-Rα, and fibroblast growth factor receptors. The present work aimed at analyzing the SOCS1 cell signaling and expression of proteins relevant to tumor development. An RNA microarray analysis of B16F10-Nex2 melanoma cells with SOCS1 silenced by shRNAi-SOCS1 was undertaken in comparison with cells transduced with the empty vector. Among 609 differentially expressed genes, c-Kit, Met and EphA3 cytokine/tyrosine-kinase (TK) receptors were down regulated. A significant decrease in the expression of TK receptors, the phosphorylation of mediators of ERK1/2 and p38 pathways and STAT3 (S727) were observed. Subcutaneous immunization with shR-SOCS1-transduced viable tumor cells rendered protection against melanoma in a syngeneic model, with decreased expression of PD-L1 and of matrix metallo-proteinases (MMPs) and CD-10 in those cells. The present work shows the role of SOCS1 in murine melanoma development and the potential of SOCS1-silenced tumor cells in raising an effective anti-melanoma immune response.

Titanium With Nanotopography Induces Osteoblast Differentiation by Regulating Endogenous Bone Morphogenetic Protein Expression and Signaling Pathway.

We aimed at evaluating the effect of titanium (Ti) with nanotopography (Nano) on the endogenous expression of BMP-2 and BMP-4 and the relevance of this process to the nanotopography-induced osteoblast differentiation. MC3T3-E1 cells were grown on Nano and machined (Machined) Ti surfaces and the endogenous BMP-2/4 expression and the effect of BMP receptor BMPR1A silencing in both osteoblast differentiation and expression of genes related to TGF-ß/BMP signaling were evaluated. Nano supported higher BMP-2 gene and protein expression and upregulated the osteoblast differentiation compared with Machined Ti surface. The BMPR1A silencing inhibited the osteogenic potential induced by Nano Ti surface as indicated by reduced alkaline phosphatase (ALP), osteocalcin and RUNX2 gene expression, RUNX2 protein expression and ALP activity. In addition, the expression of genes related to TGF-ß/BMP signaling was deeply affected by BMPR1A-silenced cells grown on Nano Ti surface. In conclusion, we have demonstrated for the first time that nanotopography induces osteoblast differentiation, at least in part, by upregulating the endogenous production of BMP-2 and modulating BMP signaling pathway. J. Cell. Biochem. 117: 1718-1726, 2016. © 2015 Wiley Periodicals, Inc.

Cellular and molecular characterization of a novel primary osteoblast culture from the vertebrate model organism Xenopus tropicalis.

Osteogenesis is the fundamental process by which bones are formed, maintained and regenerated. The osteoblasts deposit the bone mineralized matrix by secreting large amounts of extracellular proteins and by allowing the biochemical conditions for the nucleation of hydroxyapatite crystals. Normal bone formation requires a tight control of osteoblastic activity, and therefore, osteoblasts represent a major focus of interest in biomedical research. Several crucial features of osteogenesis can be readily recapitulated using murine, avian and fish primary and immortalized osteoblastic cultures. Here, we describe a novel and straightforward in vitro culture of primary osteoblasts from the amphibian Xenopus tropicalis, a major vertebrate model organism. X. tropicalis osteoblasts can readily be extracted from the frontoparietal bone of pre-metamorphosing tadpole skulls by series of gentle protease treatments. Such primary cultures efficiently proliferate and can conveniently be grown at room temperature, in the absence of CO2, on a variety of substrates. X. tropicalis primary osteoblasts express well-characterized genes known to be active during osteogenesis of teleost fish, chick, mouse and human. Upon differentiation, such cultures mineralize and activate DMP1, an osteocyte-specific gene. Importantly, X. tropicalis primary osteoblasts can be efficiently transfected and respond to the forced activation of the bone morphogenetic protein pathway by increasing their nuclear levels of phospho-Smad. Therefore, this novel primary culture is amenable to experimental manipulations and represents a valuable tool for improving our understanding of the complex network of molecular interactions that govern vertebrate bone formation.

Effect of BMPRIB gene silencing by siRNA on apoptosis and steroidogenesis of porcine granulosa cells.

Bone morphogenetic proteins (BMPs) are the key factors in maintaining cell growth and differentiation in ovaries. BMPs initiate signaling by assembling BMP receptors and activating Smads, which in turn alter the expression of target genes. However, little is known about the effect of the deletion of the Bone morphogenetic protein receptor type IB (BMPRIB) on porcine granulosa cell (GCs). The objective of this study was to determine the effects of BMPRIB gene silencing, by small interfering RNA (siRNA), on the apoptosis and steroidogenesis of porcine GCs, and the expression of cell cycle-related and apoptosis-related genes. Results indicate that the BMPRIB siRNA caused specific inhibition of BMPRIB mRNA expression after transfection. Knockdown of the BMPRIB gene significantly inhibited porcine GCs proliferation and estradiol production, while inducing apoptosis of porcine GCs. Additionally, the declined expression of the BMPRIB gene changed the expressions of CylinD2, Cdk2, Bcl-2, and Cyp19a1. These findings provide an important role of BMPRIB in the regulation of apoptosis and steroidogenesis of porcine GCs.

Effects of FSH on the expression of receptors for oocyte-secreted factors and members of the EGF-like family during in vitro maturation in cattle.

FSH induces expansion of bovine cumulus-oocyte complexes (COCs) in cattle, which can be enhanced by oocyte-secreted factors (OSFs). In this study it was hypothesised that FSH stimulates COC expansion in part from direct stimulation of the epidermal growth factor (EGF)-like ligands amphiregulin (AREG), epiregulin (EREG) and betacellulin (BTC), but also in part through regulation of OSFs or their receptors in cumulus cells. Bovine COCs were cultured in defined medium with graded doses of FSH. In the absence of FSH, COCs did not expand. FSH caused cumulus expansion, and increased the abundance of AREG and EREG mRNA in a time- and dose-dependent manner, but decreased BTC mRNA levels. FSH had modest stimulatory effects on the levels of mRNA encoding the bone morphogenetic protein 15 (BMP15) receptor, BMPR1B, in cumulus cells, but did not alter mRNA expression of the growth and differentiation factor 9 (GDF9) receptor, TGFBR1. More interestingly, FSH dramatically stimulated levels of mRNA encoding two receptors for fibroblast growth factors (FGF), FGFR2C and FGFR3C, in cumulus cells. FSH also stimulated mRNA expression of FGFR1B, but not of FGFR2B in cumulus cells. Based on dose-response studies, FGFR3C was the receptor most sensitive to the influence of FSH. This study demonstrates that FSH stimulates the expression of EGF-like factors in bovine cumulus cells, and provides evidence that FSH differently regulates the expression of distinct receptors for OSFs in cumulus cells.

BMPRIB and BMPRII mRNA expression levels in goat ovarian follicles and the in vitro effects of BMP-15 on preantral follicle development.

This study evaluated the levels of bone morphogenetic protein receptors BMPRIB and BMPRII mRNA in goat follicles and the effects of bone morphogenetic protein-15 (BMP-15) on the in vitro development of cultured preantral follicles. Real-time polymerase chain reaction (PCR) was used to analyze the levels of BMPRIB and BMPRII mRNA in caprine preantral follicles and in small and large antral follicles. Preantral follicles (≥150 µm) were also isolated from goat ovaries and cultured for 18 days in α-MEM(+) supplemented with or without BMP-15 (10, 50, or 100 ng/ml). At the end of culture, some follicles were fixed for ultrastructural evaluation. Real-time PCR showed a reduction in BMPRII mRNA levels from the primary to secondary follicles. Higher levels of BMPRIB mRNA were observed in granulosa/theca cells from large antral follicles compared with small antral follicles. Moreover, BMPRII mRNA was expressed to a greater extent in cumulus-oocyte complexes from large antral follicles than in their respective granulosa/theca cells. In culture, 50 ng/ml BMP-15 positively influenced antral cavity formation and follicle growth after 18 days and also maintained follicular integrity. Thus, BMPRIB and BMPRII mRNAs are present in all follicular categories. BMP-15 (50 ng/ml) stimulates growth, antrum formation and the ultrastructural integrity of isolated caprine preantral follicles after 18 days of culture.