Bone morphogenetic proteins (BMPs) as regulators of dorsal forebrain development

Development ◽  
1997 ◽  
Vol 124 (11) ◽  
pp. 2203-2212 ◽  
Author(s):  
Y. Furuta ◽  
D.W. Piston ◽  
B.L. Hogan

Bone Morphogenetic Proteins (BMPs) play crucial roles in a variety of developmental processes, but their functions during early vertebrate brain development are largely unknown. To investigate this problem, we have compared by in situ hybridization the expression of five Bmp genes belonging to the Drosophila Decapentaplegic (Bmp2 and Bmp4) and 60A subgroups (Bmp5, Bmp6 and Bmp7). Striking co-expression of these Bmps is observed within the dorsomedial telencephalon, coincident with a future site of choroid plexus development. Bmp co-expression overlaps that of Msx1 and Hfh4, and is complementary to that of Bf1. The domain of Bmp co-expression is also associated with limited growth of the neuroectoderm, as revealed by morphological observation, reduced cell proliferation, and increased local programmed cell death. In vitro experiments using explants from the embryonic lateral telencephalic neuroectoderm reveal that exogenous BMP proteins (BMP4 and BMP2) induce expression of Msx1 and inhibit Bf1 expression, a finding consistent with their specific expression patterns in vivo. Moreover, BMP proteins locally inhibit cell proliferation and increase apoptosis in the explants. These results provide evidence that BMPs function during regional morphogenesis of the dorsal telencephalon by regulating specific gene expression, cell proliferation and local cell death.

2019 ◽  
Vol 20 (15) ◽  
pp. 3679 ◽  
Author(s):  
Lin Chen ◽  
Alyne Simões ◽  
Zujian Chen ◽  
Yan Zhao ◽  
Xinming Wu ◽  
...  

Wounds within the oral mucosa are known to heal more rapidly than skin wounds. Recent studies suggest that differences in the microRNAome profiles may underlie the exceptional healing that occurs in oral mucosa. Here, we test whether skin wound-healing can be accelerating by increasing the levels of oral mucosa-specific microRNAs. A panel of 57 differentially expressed high expresser microRNAs were identified based on our previously published miR-seq dataset of paired skin and oral mucosal wound-healing [Sci. Rep. (2019) 9:7160]. These microRNAs were further grouped into 5 clusters based on their expression patterns, and their differential expression was confirmed by TaqMan-based quantification of LCM-captured epithelial cells from the wound edges. Of these 5 clusters, Cluster IV (consisting of 8 microRNAs, including miR-31) is most intriguing due to its tissue-specific expression pattern and temporal changes during wound-healing. The in vitro functional assays show that ectopic transfection of miR-31 consistently enhanced keratinocyte proliferation and migration. In vivo, miR-31 mimic treatment led to a statistically significant acceleration of wound closure. Our results demonstrate that wound-healing can be enhanced in skin through the overexpression of microRNAs that are highly expressed in the privileged healing response of the oral mucosa.


1996 ◽  
Vol 16 (6) ◽  
pp. 2777-2786 ◽  
Author(s):  
V Gailus-Durner ◽  
J Xie ◽  
C Chintamaneni ◽  
A K Vershon

The meiosis-specific gene HOP1, which encodes a component of the synaptonemal complex, is controlled through two regulatory elements, UASH and URS1H. Sites similar to URS1H have been identified in the promoter region of virtually every early meiosis-specific gene, as well as in many promoters of nonmeiotic genes, and it has been shown that the proteins that bind to this site function to regulate meiotic and nonmeiotic transcription. Sites similar to the UASH site have been found in a number of meiotic and nonmeiotic genes as well. Since it has been shown that UASH functions as an activator site in vegetative haploid cells, it seemed likely that the factors binding to this site regulate both meiotic and nonmeiotic transcription. We purified the factor binding to the UASH element of the HOP1 promoter. Sequence analysis identified the protein as Abf1 (autonomously replicating sequence-binding factor 1), a multifunctional protein involved in DNA replication, silencing, and transcriptional regulation. We show by mutational analysis of the UASH site, that positions outside of the proposed UASH consensus sequence (TNTGN[A/T]GT) are required for DNA binding in vitro and transcriptional activation in vivo. A new UASH consensus sequence derived from this mutational analysis closely matches a consensus Abf1 binding site. We also show that an Abf1 site from a nonmeiotic gene can replace the function of the UASH site in the HOP1 promoter. Taken together, these results show that Abf1 functions to regulate meiotic gene expression.


2020 ◽  
Vol 27 (7) ◽  
pp. 2081-2098 ◽  
Author(s):  
Ishani Das ◽  
Helge Gad ◽  
Lars Bräutigam ◽  
Linda Pudelko ◽  
Rainer Tuominen ◽  
...  

AbstractCutaneous malignant melanoma (CMM) is the deadliest form of skin cancer and clinically challenging due to its propensity to develop therapy resistance. Reactive oxygen species (ROS) can induce DNA damage and play a significant role in CMM. MTH1 protein protects from ROS damage and is often overexpressed in different cancer types including CMM. Herein, we report that MTH1 inhibitor TH1579 induced ROS levels, increased DNA damage responses, caused mitotic arrest and suppressed CMM proliferation leading to cell death both in vitro and in an in vivo xenograft CMM zebrafish disease model. TH1579 was more potent in abrogating cell proliferation and inducing cell death in a heterogeneous co-culture setting when compared with CMM standard treatments, vemurafenib or trametinib, showing its broad anticancer activity. Silencing MTH1 alone exhibited similar cytotoxic effects with concomitant induction of mitotic arrest and ROS induction culminating in cell death in most CMM cell lines tested, further emphasizing the importance of MTH1 in CMM cells. Furthermore, overexpression of receptor tyrosine kinase AXL, previously demonstrated to contribute to BRAF inhibitor resistance, sensitized BRAF mutant and BRAF/NRAS wildtype CMM cells to TH1579. AXL overexpression culminated in increased ROS levels in CMM cells. Moreover, silencing of a protein that has shown opposing effects on cell proliferation, CAV-1, decreased sensitivity to TH1579 in a BRAF inhibitor resistant cell line. AXL-MTH1 and CAV-1-MTH1 mRNA expressions were correlated as seen in CMM clinical samples. Finally, TH1579 in combination with BRAF inhibitor exhibited a more potent cell killing effect in BRAF mutant cells both in vitro and in vivo. In summary, we show that TH1579-mediated efficacy is independent of BRAF/NRAS mutational status but dependent on the expression of AXL and CAV-1.


Blood ◽  
1998 ◽  
Vol 92 (12) ◽  
pp. 4622-4631 ◽  
Author(s):  
William L. Stanford ◽  
Georgina Caruana ◽  
Katherine A. Vallis ◽  
Maneesha Inamdar ◽  
Michihiro Hidaka ◽  
...  

Abstract We have developed a large-scale, expression-based gene trap strategy to perform genome-wide functional analysis of the murine hematopoietic and vascular systems. Using two different gene trap vectors, we have isolated embryonic stem (ES) cell clones containing lacZreporter gene insertions in genes expressed in blood island and vascular cells, muscle, stromal cells, and unknown cell types. Of 79 clones demonstrating specific expression patterns, 49% and 16% were preferentially expressed in blood islands and/or the vasculature, respectively. The majority of ES clones that expressedlacZ in blood islands also expressed lacZ upon differentiation into hematopoietic cells on OP9 stromal layers. Importantly, the in vivo expression of the lacZ fusion products accurately recapitulated the observed in vitro expression patterns. Expression and sequence analysis of representative clones suggest that this approach will be useful for identifying and mutating novel genes expressed in the developing hematopoietic and vascular systems.


Blood ◽  
1998 ◽  
Vol 92 (12) ◽  
pp. 4622-4631 ◽  
Author(s):  
William L. Stanford ◽  
Georgina Caruana ◽  
Katherine A. Vallis ◽  
Maneesha Inamdar ◽  
Michihiro Hidaka ◽  
...  

We have developed a large-scale, expression-based gene trap strategy to perform genome-wide functional analysis of the murine hematopoietic and vascular systems. Using two different gene trap vectors, we have isolated embryonic stem (ES) cell clones containing lacZreporter gene insertions in genes expressed in blood island and vascular cells, muscle, stromal cells, and unknown cell types. Of 79 clones demonstrating specific expression patterns, 49% and 16% were preferentially expressed in blood islands and/or the vasculature, respectively. The majority of ES clones that expressedlacZ in blood islands also expressed lacZ upon differentiation into hematopoietic cells on OP9 stromal layers. Importantly, the in vivo expression of the lacZ fusion products accurately recapitulated the observed in vitro expression patterns. Expression and sequence analysis of representative clones suggest that this approach will be useful for identifying and mutating novel genes expressed in the developing hematopoietic and vascular systems.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1714-1714
Author(s):  
Maria Belen Almejun ◽  
Mercedes Borge ◽  
Ana Colado ◽  
Enrique Podaza ◽  
Denise Risnik ◽  
...  

Abstract Leukemic cells from CLL patients can survive and proliferate within lymphoid tissues where the supportive microenvironment favors their accumulation. We have previously reported that the activation of CLL cells reduces the expression of the main receptor for sphingosine 1-phosphate (S1P) (Borge M, J Immunol, 2014), a bioactive phospholipid that participates in lymphocyte egress from lymphoid tissues. S1P also mediates several biological functions, including cell growth stimulation and protection of apoptosis, through receptor independent intracellular mechanisms. S1P is generated by two isoforms of sphingosine kinases (SK1/2) and its levels are tightly controlled via degradation by intracellular S1P lyases (S1PL). Several studies have implicated the SK/S1P/S1PL pathway as an essential regulator of cell proliferation and survival in different cancer cells. The aims of our study were: a) to evaluate the expression of SK and S1PL in CLL cells, b) to assess whether key microenvironment signals are able to modulate this expression and c) to evaluate the effect of SK inhibitors on the activation and survival of the leukemic clone. We measured the basal expression of SK and S1PL by qRT-PCR on purified B cells from CLL patients (n=22) and aged-matched healthy donors (n=9), and found that CLL cells express high levels of SK1, favoring an increased SK1/S1PL ratio in the malignant clone compared to healthy B lymphocytes ( p<0.05). Similar results were obtained when SK2 was evaluated. The in vitro activation of CLL cells with anti-IgM+CD40L increased SK1/S1PL ratio (n=10, p<0.01) and the expression of the activation marker CD69. To evaluate the expression of SK1/S1PL within in vivo activated CLL cell subpopulations, we segregated the proliferative fraction (PF) of circulating CLL cells from the quiescent fraction (QF) in the same sample. As it was previously described, this PF is characterized by the presence of an active class-switch recombination process and a high expression of proliferation-related genes, such as Ki-67, c-myc, CD49d, and p27-Kip1 (Palacios F, Blood, 2010). Interestingly, SK1/S1PL ratio was increased in the PF compared with the QF (n=3). Additionally, bone marrow leukemic cells expressing high levels of CD38, which defines a subpopulation of activated lymphocytes, showed a higher S1P/S1PL ratio compared to CD38 low or negative counterparts (n=3),showing that the in vivo activated CLL cells expressed higher ratios of SK1/S1PL compared with the rest of the leukemic clone. Finally, we wondered whether the inhibition of SK impairs the survival, activation and proliferation of the leukemic clone. To this aim we employed a commercial selective SK1 and SK2 inhibitor (SKI-II, 5 and 15μM), which did not affect cell viability (n=10, evaluated at 24, 48, 72 and 96hs). However, it was able to impair the expected upregulation of CD69 induced by IgM+CD40L at 24hs (n=10, p<0.001) and the leukemic cell proliferation evaluated by CFSE dilution assay at 96hs (n=10 , p<0.001). Moreover, while SKI-II did not increase the sensitivity of CLL cells to Fludarabine or Bendamustine, it was able to enhance the cell death induced by Ibrutinib (0.3 and 3μM) (n=5, p<0.05 and p<0.01 respectively). Taking together, our results suggest that SK/S1P/S1PL axis might participate in the accumulation of the malignant clone in CLL patients and the disruption of this pathway might be a potentially effective treatment option in the future. Disclosures Bezares: Janssen: Honoraria. Gamberale:Janssen: Honoraria.


2021 ◽  
Author(s):  
Divya Lodha ◽  
Jamuna R. Subramaniam

Abstract In various neurological and neurodegenerative diseases (ND), motor neurons (MN) of the spinal cord are affected leading to movement impairments. The ND, Amyotrophic Lateral Sclerosis (ALS), is caused due to MN degeneration. ALS afflicts athletes and other major sports personalities, who generally consume fructose enriched sports drinks. Recently, we have reported that high fructose (F5%) impairs the metabolic activity in the NSC-34, MN cell line and reduces the healthspan of C. elegans. But how fructose impacts the MNs either in vitro or in vivo in the long term is not understood. Here we report, to our surprise, that high fructose (F5%) treatment of NSC-34 leads to differentiation of 1-2% of cells with progressive neurite extension. They could be maintained for 80 days in vitro with 5% CO2 and O2 at 18.8%. On the contrary, 5% fructose significantly reduced cell viability by ~85% and inhibited cell proliferation by Day10. Nuclear staining displayed multiple nuclei in the cells indicative of cytokinesis inhibition which led to the lack of cell proliferation. Further, F5% significantly increased ROS levels (^~34%), the potential cause for reduced viability. In addition, no induction of expression of the master oxidative stress response regulator, the transcription factor, nrf-2, or the downstream effector, sod1, was evident. Despite the adverse effects, in the absence of any, F5% is a potential strategy to maintain at least a small percentage of MNs for a long time, ~45 days in vitro, which also reinforces the Redox-Cell death versus cell survival conundrum.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Attila Szabo ◽  
Ibrahim A. Akkouh ◽  
Matthieu Vandenberghe ◽  
Jordi Requena Osete ◽  
Timothy Hughes ◽  
...  

AbstractWhile neurodevelopmental abnormalities have been associated with schizophrenia (SCZ), the role of astroglia in disease pathophysiology remains poorly understood. In the present study, we used a human induced pluripotent stem cell (iPSC)-derived astrocyte model to investigate the temporal patterns of astroglia differentiation during developmental stages critical for SCZ using RNA sequencing. The model generated astrocyte-specific gene expression patterns during differentiation that corresponded well to astroglia-specific expression signatures of in vivo cortical fetal development. Using this model we identified SCZ-specific expression dynamics, and found that SCZ-associated differentially expressed genes were significantly enriched in the medial prefrontal cortex, striatum, and temporal lobe, targeting VWA5A and ADAMTS19. In addition, SCZ astrocytes displayed alterations in calcium signaling, and significantly decreased glutamate uptake and metalloproteinase activity relative to controls. These results implicate novel transcriptional dynamics in astrocyte differentiation in SCZ together with functional changes that are potentially important biological components of SCZ pathology.


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