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Developmental Biology
Retaining mTeSR1 Medium during Hepatic Differentiation Facilitates Hepatocyte-Like Cell Survival by Decreasing Apoptosis.
Dec 11, 2018   Cellular Physiology And Biochemistry : International Journal Of Experimental Cellular Physiology, Biochemistry, And Pharmacology
Hou J, Long Y, Hu B, Huang S, Xu G, Gao T, Wu F, Li Y, Wu ZK
Retaining mTeSR1 Medium during Hepatic Differentiation Facilitates Hepatocyte-Like Cell Survival by Decreasing Apoptosis.
Dec 11, 2018
Cellular Physiology And Biochemistry : International Journal Of Experimental Cellular Physiology, Biochemistry, And Pharmacology
BACKGROUND/AIMS: Hepatocyte-like cells derived from human pluripotent stem cells could be an important cell source for hepatocyte transplantation. The present study investigated the effect of retaining mTeSR1 medium during hepatic differentiation on hepatocyte-like cells in vitro. METHODS: Human embryonic stem cell line H1 were treated with activin A and bone morphogenetic protein 4 (BMP4) for definitive endoderm (DE) cell induction and subsequently treated with BMP2 and fibroblast growth factor 4 (FGF4) for early hepatic cell induction. Hepatocyte growth factor (HGF) and fibroblast growth factor (KGF) were added for early hepatic cell expansion and then mixed with oncostatin-M for maturation. During DE induction, 0%, 25%, 50% and 75% concentrations of mTeSR1 medium were separately added for early hepatic induction and expansion. For optimization, the expression levels of SRY-related HMG-box 17 (SOX17) and forkhead box A2 (FOXA2) at day 4, alpha fetoprotein (AFP) and hepatocyte nuclear factor 4α (HNF4α) at day 15, and albumin (ALB) at day 25 were quantified in differentiated cells by qRT-PCR. The ALB-positive cell proportion was measured by flow cytometry. Functional tests including ALB secretion and indocyanine green (ICG) angiography uptake and release by ELISA, urea production by urea assay kit, and glycogen storage ability by periodic acid Schif reaction (PAS) staining were performed in the differentiated cells. The induced pluripotent stem (iPS) cells were used to examine whether the optimized method was suitable for differentiating iPS cells. DE and hepatic markers were detected by immunostaining, and functional testing was performed as described above. Flow cytometry with an Annexin V-FITC apoptosis detection kit and fluorescence microscopy with Hoechst 33258 were used to analyze apoptosis in differentiated cells derived from H1 cells. RESULTS: All differentiated cells with retention of 0%, 25%, 50% and 75% mTeSR1 expressed SOX17, FOXA2, AFP, HNF4α, and ALB, while higher expression levels were observed in differentiated cells in the 0% and 25% groups. The flow cytometry results showed that the proportion of ALB-positive differentiated cells derived from H1 cells was higher in the 25% mTeSR1 group than in other groups. However, no significant difference in ALB secretion, urea production, ICG uptake and release and glycogen storage ability was detected between the 25% and 0% groups. The iPS cells could differentiate into hepatocyte-like cells with 25% mTeSR1 retention. The apoptosis ratio of differentiated cells was lower in the 25% mTeSR1 group than in the 0% mTeSR1 group. CONCLUSION: Retaining 25% mTeSR1 medium during hepatic differentiation has been proposed to increase the percentage of ALB-positive cells and cell survival by decreasing cell apoptosis.
The Caenorhabditis elegans SMOC-1 Protein Acts Cell Non-autonomously To Promote Bone Morphogenetic Protein Signaling.
Dec 06, 2018   Genetics
DeGroot MS, Shi H, Eastman A, McKillop AN, Liu J
The Caenorhabditis elegans SMOC-1 Protein Acts Cell Non-autonomously To Promote Bone Morphogenetic Protein Signaling.
Dec 06, 2018
Genetics
Bone morphogenetic protein (BMP) signaling regulates many different developmental and homeostatic processes in metazoans. The BMP pathway is conserved in Caenorhabditis elegans, and is known to regulate body size and mesoderm development. We have identified the C. elegans smoc-1 (Secreted MOdular Calcium binding protein-1) gene as a new player in the BMP pathway. smoc-1(0) mutants have a small body size, while overexpression of smoc-1 led to a long body size and increased expression of the RAD-SMAD BMP reporter, suggesting that SMOC-1 acts as a positive modulator of BMP signaling. Using double mutant analysis, we showed that SMOC-1 antagonizes the function of the glypican LON-2 and acts through the BMP ligand DBL-1 to regulate BMP signaling. Moreover, SMOC-1 appears to specifically regulate BMP signaling without significant involvement in a TGFβ-like pathway that regulates dauer development. We found that smoc-1 is expressed in multiple tissues, including cells of the pharynx, intestine, and posterior hypodermis, and that the expression of smoc-1 in the intestine is positively regulated by BMP signaling. We further established that SMOC-1 functions cell non-autonomously to regulate body size. Human SMOC1 and SMOC2 can each partially rescue the smoc-1(0) mutant phenotype, suggesting that SMOC-1's function in modulating BMP signaling is evolutionarily conserved. Together, our findings highlight a conserved role of SMOC proteins in modulating BMP signaling in metazoans.
A transcriptomics analysis of the Tbx5 paralogues in zebrafish.
Dec 11, 2018   PloS One
Boyle Anderson EAT, Ho RK
A transcriptomics analysis of the Tbx5 paralogues in zebrafish.
Dec 11, 2018
PloS One
TBX5 is essential for limb and heart development. Mutations in TBX5 are associated with Holt-Oram syndrome in humans. Due to the teleost specific genome duplication, zebrafish have two copies of TBX5: tbx5a and tbx5b. Both of these genes are expressed in regions of the lateral plate mesoderm and retina. In this study, we perform comparative RNA sequencing analysis on zebrafish embryos during the stages of lateral plate mesoderm migration. This work shows that knockdown of the Tbx5 paralogues results in altered gene expression in many tissues outside of the lateral plate mesoderm, especially in the somitic mesoderm and the intermediate mesoderm. Specifically, knockdown of tbx5b results in changes in somite size, in the differentiation of vasculature progenitors and in later patterning of trunk blood vessels.
A Gata4 nuclear GFP transcriptional reporter to study endoderm and cardiac development in the mouse.
Dec 11, 2018   Biology Open
Simon CS, Zhang L, Wu T, Cai W, Saiz N, Nowotschin S, Cai CL, Hadjantonakis AK
A Gata4 nuclear GFP transcriptional reporter to study endoderm and cardiac development in the mouse.
Dec 11, 2018
Biology Open
The GATA zinc-finger transcription factor GATA4 is expressed in a variety of tissues during mouse embryonic development and in adult organs. These include the primitive endoderm of the blastocyst, visceral endoderm of the early post-implantation embryo, as well as lateral plate mesoderm, developing heart, liver, lung and gonads. Here, we generate a novel Gata4 targeted allele used to generate both a Gata4H2B-GFP transcriptional reporter and a Gata4FLAG fusion protein to analyse dynamic expression domains. We demonstrate that the Gata4H2B-GFP transcriptional reporter faithfully recapitulates known sites of Gata4 mRNA expression and correlates with endogenous GATA4 protein levels. This reporter labels nuclei of Gata4 expressing cells and is suitable for time-lapse imaging and single cell analyses. As such, this Gata4H2B-GFP allele will be a useful tool for studying Gata4 expression and transcriptional regulation.This article has an associated First Person interview with the first author of the paper.
Wnt/β-catenin-mediated signaling re-activates proliferation of matured cardiomyocytes.
Dec 11, 2018   Stem Cell Research & Therapy
Fan Y, Ho BX, Pang JKS, Pek NMQ, Hor JH, Ng SY, Soh BS
Wnt/β-catenin-mediated signaling re-activates proliferation of matured cardiomyocytes.
Dec 11, 2018
Stem Cell Research & Therapy
BACKGROUND: The Wnt/β-catenin signaling pathway plays an important role in the development of second heart field (SHF Isl1+) that gives rise to the anterior heart field (AHF) cardiac progenitor cells (CPCs) for the formation of the right ventricle, outflow tract (OFT), and a portion of the inflow tract (IFT). During early cardiogenesis, these AHF CPCs reside within the pharyngeal mesoderm (PM) that provides a microenvironment for them to receive signals that direct their cell fates. Here, N-cadherin, which is weakly expressed by CPCs, plays a significant role by promoting the adhesion of CPCs within the AHF, regulating β-catenin levels in the cytoplasm to maintain high Wnt signaling and cardioproliferation while also preventing the premature differentiation of CPCs. On the contrary, strong expression of N-cadherin observed throughout matured myocardium is associated with downregulation of Wnt signaling due to β-catenin sequestration at the cell membrane, inhibiting cardioproliferation. As such, upregulation of Wnt signaling pathway to enhance cardiac tissue proliferation in mature cardiomyocytes can be explored as an interesting avenue for regenerative treatment to patients who have suffered from myocardial infarction. METHODS: To investigate if Wnt signaling is able to enhance cellular proliferation of matured cardiomyocytes, we treated cardiomyocytes isolated from adult mouse heart and both murine and human ES cell-derived matured cardiomyocytes with N-cadherin antibody or CHIR99021 GSK inhibitor in an attempt to increase levels of cytoplasmic β-catenin. Immunostaining, western blot, and quantitative PCR for cell proliferation markers, cell cycling markers, and Wnt signaling pathway markers were used to quantitate re-activation of cardioproliferation and Wnt signaling. RESULTS: N-cadherin antibody treatment releases sequestered β-catenin at N-cadherin-based adherens junction, resulting in an increased pool of cytoplasmic β-catenin, similar in effect to CHIR99021 GSK inhibitor treatment. Both treatments therefore upregulate Wnt signaling successfully and result in significant increases in matured cardiomyocyte proliferation. CONCLUSION: Although both N-cadherin antibody and CHIR99021 treatment resulted in increased Wnt signaling and cardioproliferation, CHIR99021 was found to be the more effective treatment method for human ES cell-derived cardiomyocytes. Therefore, we propose that CHIR99021 could be a potential therapeutic option for myocardial infarction patients in need of regeneration of cardiac tissue.
Conservation analysis and pathogenicity prediction of mutant genes of ectodysplasin a.
Dec 11, 2018   BMC Medical Genetics
He F, Wang H, Zhang X, Gao Q, Guo F, Chen C
Conservation analysis and pathogenicity prediction of mutant genes of ectodysplasin a.
Dec 11, 2018
BMC Medical Genetics
BACKGROUND: Hypohidrotic ectodermal dysplasia (HED) is a common recessive X-linked hereditary disease that affects the development of ectoderm. Gene mutations of ectodysplasin A (EDA) play key roles in process of this disease. In our preliminary study, three unknown mutation sites (c.878 T > G, c.663-697del and c.587-615del) were detected from the pedigrees of HED. METHODS: Conservation analysis of the related homologous proteins in 3 unknown EDA gene mutation sites was conducted using the University of California Santa Cruz (UCSC) Genome Browser database. SIFT and PolyPhen-2, the online gene function prediction software, were utilized to predict the pathogenicity of point mutation of c.878 T > G. RESULTS: All three unknown mutation sites were located in the highly-conserved region of EDA and possessed strong amino acid conservation among different species. In addition, the results of the pathogenicity prediction of point mutation of c.878 T > G by SIFT (P = 0.00) and PolyPhen-2 (S = 0.997) demonstrated that the mutation site had considerable pathogenicity theoretically. CONCLUSIONS: The EDA mutations of c.878 T > G, c.663-697del and c.587-615del may be responsible for the pathogenesis of HED in their pedigrees.
Screening for insulin-independent pathways that modulate glucose homeostasis identifies androgen receptor antagonists.
Dec 06, 2018   ELife
Mullapudi ST, Helker CS, Boezio GL, Maischein HM, Sokol AM, Guenther S, Matsuda H, Kubicek S, Graumann J, Yang YHC, Stainier DY
Screening for insulin-independent pathways that modulate glucose homeostasis identifies androgen receptor antagonists.
Dec 06, 2018
ELife
Pathways modulating glucose homeostasis independently of insulin would open new avenues to combat insulin resistance and diabetes. Here, we report the establishment, characterization and use of a vertebrate 'insulin-free' model to identify insulin-independent modulators of glucose metabolism. insulin knockout zebrafish recapitulate core characteristics of diabetes and survive only up to larval stages. Utilizing a highly efficient endoderm transplant technique, we generated viable chimeric adults that provide the large numbers of insulin mutant larvae required for our screening platform. Using glucose as a disease-relevant readout, we screened 2233 molecules and identified 3 that consistently reduced glucose levels in insulin mutants. Most significantly, we uncovered an insulin-independent beneficial role for androgen receptor antagonism in hyperglycemia, mostly by reducing fasting glucose levels. Our study proposes therapeutic roles for androgen signaling in diabetes and, more broadly, offers a novel in vivo model for rapid screening and decoupling of insulin-dependent and -independent mechanisms.
Single-cell mapping of lineage and identity in direct reprogramming.
Dec 13, 2018   Nature Add nature.com free-link Cancel
Biddy BA, Kong W, Kamimoto K, Guo C, Waye SE, Sun T, Morris SA
Single-cell mapping of lineage and identity in direct reprogramming.
Dec 13, 2018
Nature
Direct lineage reprogramming involves the conversion of cellular identity. Single-cell technologies are useful for deconstructing the considerable heterogeneity that emerges during lineage conversion. However, lineage relationships are typically lost during cell processing, complicating trajectory reconstruction. Here we present 'CellTagging', a combinatorial cell-indexing methodology that enables parallel capture of clonal history and cell identity, in which sequential rounds of cell labelling enable the construction of multi-level lineage trees. CellTagging and longitudinal tracking of fibroblast to induced endoderm progenitor reprogramming reveals two distinct trajectories: one leading to successfully reprogrammed cells, and one leading to a 'dead-end' state, paths determined in the earliest stages of lineage conversion. We find that expression of a putative methyltransferase, Mettl7a1, is associated with the successful reprogramming trajectory; adding Mettl7a1 to the reprogramming cocktail increases the yield of induced endoderm progenitors. Together, these results demonstrate the utility of our lineage-tracing method for revealing the dynamics of direct reprogramming.
Loss of Lgr4 inhibits differentiation, migration and apoptosis, and promotes proliferation in bone mesenchymal stem cells.
Dec 11, 2018   Journal Of Cellular Physiology
Sun P, Jia K, Zheng C, Zhu X, Li J, He L, Siwko S, Xue F, Liu M, Luo J
Loss of Lgr4 inhibits differentiation, migration and apoptosis, and promotes proliferation in bone mesenchymal stem cells.
Dec 11, 2018
Journal Of Cellular Physiology
The key signaling networks regulating bone marrow mesenchymal stem cells (BMSCs) are poorly defined. Lgr4, which belongs to the leucine-rich repeat-containing G protein-coupled receptor (LGR) family, is widely expressed in multiple tissues from early embryogenesis to adulthood. We investigated whether Lgr4 functions in BMSCs and in osteogenesis, adipogenesis, and skeletal myoblasts, using mice with a β-geo gene trap inserted into the Lgr4 gene. Abundant Lgr4 expression was detected in skeletal, adipose and muscular tissue of Lgr4+/- mice at E16.5 by β-gal staining, and Lgr4-deficiency promoted BMSC proliferation (16 ± 4 in wild-type [WT] and 28 ± 2 in Lgr4-/- ) using colony forming units-fibroblast assay, while suppressing BMSC migration (from 103 ± 18 in WT to 57 ± 10 in Lgr4-/- ) by transwell migration assay and apoptosis ratio (from 0.0720 ± 0.0123 to 0.0189 ± 0.0051) by annexin V staining assay. Deletion of Lgr4 decreased bone mass (BV/TV from 19.16 ± 2.14 in WT mice to 10.36 ± 1.96 in KO) and fat mass through inhibiting BMSC differentiation to osteoblasts or adipocytes. Furthermore, LGR4-regulated osteogenic, adipogenic, and myogenic gene expression. Importantly, our data showed that loss of Lgr4-inhibited fracture healing by suppressing osteoblast differentiation. Moreover, deletion of Lgr4 in BMSCs-delayed fracture healing following stem cell therapy by BMSC transplantation. Together, our results demonstrated that LGR4 is essential for mesoderm-derived tissue development and BMSC differentiation, demonstrating that LGR4 could be a promising drug target for related diseases and a critical protein for stem cell therapy.
Correction: Divergent early mesoderm specification underlies distinct head and trunk muscle programmes in vertebrates (doi: 10.1242/dev.160945).
Dec 04, 2018   Development (Cambridge, England)
Nandkishore N, Vyas B, Javali A, Ghosh S, Sambasivan R
The Repo homeodomain transcription factor suppresses hematopoiesis in Drosophila and preserves the glial fate.
Dec 03, 2018   The Journal Of Neuroscience : The Official Journal Of The Society For Neuroscience
Trébuchet G, Cattenoz PB, Zsámboki J, Mazaud D, Siekhaus DE, Fanto M, Giangrande A
The Repo homeodomain transcription factor suppresses hematopoiesis in Drosophila and preserves the glial fate.
Dec 03, 2018
The Journal Of Neuroscience : The Official Journal Of The Society For Neuroscience
Despite their different origins, Drosophila glia and hemocytes are related cell populations that provide an immune function. Drosophila hemocytes patrol the body cavity and act as macrophages outside the nervous system whereas glia originate from the neuroepithelium and provide the scavenger population of the nervous system. Drosophila glia are hence the functional orthologs of vertebrate microglia, even though the latter are cells of immune origin that subsequently move into the brain during development. Interestingly, the Drosophila immune cells within (glia) and outside the nervous system (hemocytes) require the same transcription factor Glide/Gcm for their development. This raises the issue of how do glia specifically differentiate in the nervous system and hemocytes in the procephalic mesoderm. The Repo homeodomain transcription factor and pan-glial direct target of Glide/Gcm is known to ensure glial terminal differentiation. Here we show that Repo also takes center stage in the process that discriminates between glia and hemocytes. First, Repo expression is repressed in the hemocyte anlagen by mesoderm-specific factors. Second, Repo ectopic activation in the procephalic mesoderm is sufficient to repress the expression of hemocyte-specific genes. Third, the lack of Repo triggers the expression of hemocyte markers in glia. Thus, a complex network of tissue-specific cues biases the potential of Glide/Gcm. These data allow us to revise the concept of fate determinants and help us understand the bases of cell specification. Both sexes were analyzed.SIGNIFICANCE STATEMENTDistinct cell types often require the same pioneer transcription factor, raising the issue of how does one factor trigger different fates. In Drosophila, glia and hemocytes provide a scavenger activity within and outside the nervous system, respectively. While they both require the Glide/Gcm transcription factor, glia originate from the ectoderm, hemocytes from the mesoderm. Here we show that tissue-specific factors inhibit the gliogenic potential of Glide/Gcm in the mesoderm by repressing the expression of the homeodomain protein Repo, a major glial-specific target of Glide/Gcm. Repo expression in turn inhibits the expression of hemocyte-specific genes in the nervous system. These cell-specific networks secure the establishment of the glial fate only in the nervous system and allow cell diversification.
Improved Tol2-mediated enhancer trap identifies weakly expressed genes during liver and β cell development and regeneration in zebrafish.
Dec 03, 2018   The Journal Of Biological Chemistry
Zhong Y, Huang W, Du J, Wang Z, He J, Luo L
Improved Tol2-mediated enhancer trap identifies weakly expressed genes during liver and β cell development and regeneration in zebrafish.
Dec 03, 2018
The Journal Of Biological Chemistry
The liver and pancreas are two major digestive organs, and among the different cell types in them, hepatocytes and the insulin-producing β cells have roles in both health and diseases. Accordingly, clinicians and researchers are very interested in the mechanisms underlying the development and regeneration of liver and pancreatic β cells. Gene and enhancer traps such as Tol2 transposon-based system are useful for identifying genes potentially involved in developmental processes in the zebrafish model. Here, we developed a strategy that combines a Tol2-mediated enhancer trap and the Cre/loxP system by using loxP-flanked reporters driven by β cell- or hepatocyte-specific promoters and the upstream activating sequence (UAS)-driving Cre. Two double-transgenic reporter lines Tg(ins:loxP-CFPNTR-loxP-DsRed; 10×UAS:Cre, cryaa:Venus) and Tg(fabp10:loxP-CFPNTR-loxP-DsRed; 10×UAS:Cre, cryaa:Venus) were established to label pancreatic β cells and hepatocytes, respectively. These two double-transgenic lines were each crossed with the Tol2-enhancer trap founder lines to screen for and identify genes expressed in the β cell and hepatocytes during development. This trap system coupled with application of nitroreductase (NTR)/metronidazole (Mtz)-mediated cell ablation could identify genes expressed during regeneration. Of note, pilot enhancer traps captured transiently and weakly expressed genes such as rab3da and ensab with higher efficiencies than traditional enhancer trap systems. In conclusion, through permanent genetic labeling by Cre/loxP, this improved Tol2-mediated enhancer trap system provides a promising method to identify transiently or weakly expressed, but potentially important, genes during development and regeneration.
Haplotype-based association of two SNPs in miR-423 with unexplained recurrent pregnancy loss in a Chinese Han population.
Dec 11, 2018   Experimental Cell Research
Wang XQ, Wang H, Zhang L, Liu HN, Gao J, Wang YY, Ma X, Xia HF
Haplotype-based association of two SNPs in miR-423 with unexplained recurrent pregnancy loss in a Chinese Han population.
Dec 11, 2018
Experimental Cell Research
MicroRNAs (miRNAs) regulate diverse cellular processes such as cell differentiation, proliferation and apoptosis. Mutation in miRNAs results in various pathological conditions such as inflammation, viral infections, neurodegeneration, and autoimmunity. We have evaluated the association of miR-423 rs6505162C>A and rs8067576 A>T among patients with recurrent pregnancy loss (RPL) and controls from North China. Our study found that one SNP rs6505162C>A in miR-423 coding region was associated with the increase risk of humanunexplained RPL (URPL), but no differences were found in another SNP rs8067576 A>T. However, in two-locus haplotype analysis, miR-423-CC/TT haplotype was associated with an increased risk of URPL. The level of mature miR-423 was obviously down-regulated in cells transfected with miR-423-CC/TT haplotype. miR-423-CC/TT haplotype inhibited HTR-8/SVneo cells proliferation and migration and promoted cells apoptosis. Further experiments identified that mesoderm development candidate 1 (MESDC1) was a functionally relevant target of miR-423, and its expression was reversely regulated by miR-423. More importantly, dual-luciferase assay indicated miR-423-CC/TT haplotype decreasing miR-423 expression, could up-regulate MESDC1 expression. Collectively, our data suggest that miR-423-CC/TT haplotype in pre-miR-423 may aggravate the risk of developing URPL by influencing the level of mature miR-423 and its target gene MESDC1.
Six1 and Irx1 have reciprocal interactions during cranial placode and otic vesicle formation.
Dec 11, 2018   Developmental Biology
Sullivan CH, Majumdar HD, Neilson KM, Moody SA
Six1 and Irx1 have reciprocal interactions during cranial placode and otic vesicle formation.
Dec 11, 2018
Developmental Biology
The specialized sensory organs of the vertebrate head are derived from thickened patches of cells in the ectoderm called cranial sensory placodes. The developmental program that generates these placodes and the genes that are expressed during the process have been studied extensively in a number of animals, yet very little is known about how these genes regulate one another. We previously found via a microarray screen that Six1, a known transcriptional regulator of cranial placode fate, up-regulates Irx1 in ectodermal explants. In this study, we investigated the transcriptional relationship between Six1 and Irx1 and found that they reciprocally regulate each other throughout cranial placode and otic vesicle formation. Although Irx1 expression precedes that of Six1 in the neural border zone, its continued and appropriately patterned expression in the pre-placodal region (PPR) and otic vesicle requires Six1. At early PPR stages, Six1 expands the Irx1 domain, but this activity subsides over time and changes to a predominantly repressive effect. Likewise, Irx1 initially expands Six1 expression in the PPR, but later represses it. We also found that Irx1 and Sox11, a known direct target of Six1, reciprocally affect each other. This work demonstrates that the interactions between Six1 and Irx1 are continuous during PPR and placode development and their transcriptional effects on one another change over developmental time.
bFGF-mediated pluripotency maintenance in human induced pluripotent stem cells is associated with NRAS-MAPK signaling.
Dec 11, 2018   Cell Communication And Signaling : CCS
Haghighi F, Dahlmann J, Nakhaei-Rad S, Lang A, Kutschka I, Zenker M, Kensah G, Piekorz RP, Ahmadian MR
bFGF-mediated pluripotency maintenance in human induced pluripotent stem cells is associated with NRAS-MAPK signaling.
Dec 11, 2018
Cell Communication And Signaling : CCS
BACKGROUND: Human pluripotent stem cells (PSCs) open new windows for basic research and regenerative medicine due to their remarkable properties, i.e. their ability to self-renew indefinitely and being pluripotent. There are different, conflicting data related to the role of basic fibroblast growth factor (bFGF) in intracellular signal transduction and the regulation of pluripotency of PSCs. Here, we investigated the effect of bFGF and its downstream pathways in pluripotent vs. differentiated human induced (hi) PSCs. METHODS: bFGF downstream signaling pathways were investigated in long-term culture of hiPSCs from pluripotent to differentiated state (withdrawing bFGF) using immunoblotting, immunocytochemistry and qPCR. Subcellular distribution of signaling components were investigated by simple fractionation and immunoblotting upon bFGF stimulation. Finally, RAS activity and RAS isoforms were studied using RAS assays both after short- and long-term culture in response to bFGF stimulation. RESULTS: Our results revealed that hiPSCs were differentiated into the ectoderm lineage upon withdrawing bFGF as an essential pluripotency mediator. Pluripotency markers OCT4, SOX2 and NANOG were downregulated, following a drastic decrease in MAPK pathway activity levels. Notably, a remarkable increase in phosphorylation levels of p38 and JAK/STAT3 was observed in differentiated hiPSCs, while the PI3K/AKT and JNK pathways remained active during differentiation. Our data further indicate that among the RAS paralogs, NRAS predominantly activates the MAPK pathway in hiPSCs. CONCLUSION: Collectively, the MAPK pathway appears to be the prime signaling pathway downstream of bFGF for maintaining pluripotency in hiPSCs and among the MAPK pathways, the activity of NRAS-RAF-MEK-ERK is decreased during differentiation, whereas p38 is activated and JNK remains constant.
Adipose tissue: A natural resource for multipotent mesenchymal stem cells with potential translation to trigerminal layers.
Dec 03, 2018   Indian Journal Of Plastic Surgery : Official Publication Of The Association Of Plastic Surgeons Of India
Vyas B, Shah A, Marathe A, Ansarullah , Vyas R, Bhonde R
Adipose tissue: A natural resource for multipotent mesenchymal stem cells with potential translation to trigerminal layers.
Dec 03, 2018
Indian Journal Of Plastic Surgery : Official Publication Of The Association Of Plastic Surgeons Of India
Background: The article reports basic science research that establishes that adipose tissue (AT)-derived mesenchymal stem cells (MSCs) have a potential to transgerminal translation. Study Design: MSC confirmation was obtained by phenotypic spindle-shaped cells as well as with four positive and three negative markers. The translineage translation of adipose-derived MSCs (ADMSCs) was established. Materials and Methods: The lipoaspirate was subjected to enzymatic digestion with collagenase. Stromal vascular factor (SVF) was isolated. With two passages, pure culture of ADMSCs was obtained. They were translated to all the three germinal layers. Results: AT-derived SVF contains ~30% MSCs. They are capable of being translated into endoderm, mesoderm and ectoderm. Conclusion: AT is a rich source for MSCs, with immense research possibilities for regeneration and rejuvenation.
The Chick Caudolateral Epiblast Acts as a Permissive Niche for Generating Neuromesodermal Progenitor Behaviours.
Dec 05, 2018   Cells, Tissues, Organs
Baillie-Johnson P, Voiculescu O, Hayward P, Steventon B
The Chick Caudolateral Epiblast Acts as a Permissive Niche for Generating Neuromesodermal Progenitor Behaviours.
Dec 05, 2018
Cells, Tissues, Organs
Neuromesodermal progenitors (NMps) are a population of bipotent progenitors that maintain competence to generate both spinal cord and paraxial mesoderm throughout the elongation of the posterior body axis. Recent studies have generated populations of NMp-like cells in culture, which have been shown to differentiate to both neural and mesodermal cell fates when transplanted into either mouse or chick embryos. Here, we aim to compare the potential of mouse embryonic stem (ES) cell-derived progenitor populations to generate NMp behaviour against both undifferentiated and differentiated populations. We define NMp behaviour as the ability of cells to: (i) contribute to a significant proportion of the anterior-posterior body axis, (ii) enter into both posterior neural and somitic compartments, and (iii) retain a proportion of the progenitor population within the posterior growth zone. We compare previously identified ES cell-derived NMp-like populations to undifferentiated mouse ES cells and find that they all display similar potentials to generate NMp behaviour in vivo. To assess whether this competence is lost upon further differentiation, we generated anterior and posterior embryonic cell types through the generation of 3D gastruloids and show that NMp competence is lost within the anterior (Brachyury-negative) portion of the gastruloid. Together this suggests that in vitro-derived NMp-like cells maintain an ability to contribute to multiple germ layers that is also present within pluripotent ES cells, rather than acquiring a neuromesodermal competent state through differentiation.
Polysome profiling followed by RNA-seq of cardiac differentiation stages in hESCs.
Dec 04, 2018   Scientific Data
Pereira IT, Spangenberg L, Robert AW, Amorín R, Stimamiglio MA, Naya H, Dallagiovanna B
Polysome profiling followed by RNA-seq of cardiac differentiation stages in hESCs.
Dec 04, 2018
Scientific Data
The regulation of gene expression acts at numerous complementary levels to control and refine protein abundance. The analysis of mRNAs associated with polysomes, called polysome profiling, has been used to investigate the post-transcriptional mechanisms that are involved in different biological processes. Pluripotent stem cells are able to differentiate into a variety of cell lineages, and the cell commitment progression is carefully orchestrated. Genome-wide expression profiling has provided the possibility to investigate transcriptional changes during cardiomyogenesis; however, a more accurate study regarding post-transcriptional regulation is required. In the present work, we isolated and high-throughput sequenced ribosome-free and polysome-bound RNAs from NKX2-5eGFP/w HES3 undifferentiated pluripotent stem cells at the subsequent differentiation stages of cardiomyogenesis: embryoid body aggregation, mesoderm, cardiac progenitor and cardiomyocyte. The expression of developmental markers was followed by flow cytometry, and quality analyses were performed as technical controls to ensure high quality data. Our dataset provides valuable information about hESC cardiac differentiation and can be used to investigate genes potentially controlled by post-transcriptional mechanisms.
The Rare Neurocutaneous Disorders: Update on Clinical, Molecular, and Neuroimaging Features.
Dec 05, 2018   Topics In Magnetic Resonance Imaging : TMRI
Barros FS, Marussi VHR, Amaral LLF, da Rocha AJ, Campos CMS, Freitas LF, Huisman TAGM, Soares BP
The Rare Neurocutaneous Disorders: Update on Clinical, Molecular, and Neuroimaging Features.
Dec 05, 2018
Topics In Magnetic Resonance Imaging : TMRI
Phakomatoses, also known as neurocutaneous disorders, comprise a vast number of entities that predominantly affect structures originated from the ectoderm such as the central nervous system and the skin, but also the mesoderm, particularly the vascular system. Extensive literature exists about the most common phakomatoses, namely neurofibromatosis, tuberous sclerosis, von Hippel-Lindau and Sturge-Weber syndrome. However, recent developments in the understanding of the molecular underpinnings of less common phakomatoses have sparked interest in these disorders. In this article, we review the clinical features, current pathogenesis, and modern neuroimaging findings of melanophakomatoses, vascular phakomatoses, and other rare neurocutaneous syndromes that may also include tissue overgrowth or neoplastic predisposition.
Disruption of FOXP3-EZH2 Interaction Represents a Pathobiological Mechanism in Intestinal Inflammation.
Dec 04, 2018   Cellular And Molecular Gastroenterology And Hepatology
Bamidele AO, Svingen PA, Sagstetter MR, Sarmento OF, Gonzalez M, Braga Neto MB, Kugathasan S, Lomberk G, Urrutia RA, Faubion WA
Disruption of FOXP3-EZH2 Interaction Represents a Pathobiological Mechanism in Intestinal Inflammation.
Dec 04, 2018
Cellular And Molecular Gastroenterology And Hepatology
Background & Aims: Forkhead box protein 3 (FOXP3)+ regulatory T cell (Treg) dysfunction is associated with autoimmune diseases; however, the mechanisms responsible for inflammatory bowel disease pathophysiology are poorly understood. Here, we tested the hypothesis that a physical interaction between transcription factor FOXP3 and the epigenetic enzyme enhancer of zeste homolog 2 (EZH2) is essential for gene co-repressive function. Methods: Human FOXP3 mutations clinically relevant to intestinal inflammation were generated by site-directed mutagenesis. T lymphocytes were isolated from mice, human blood, and lamina propria of Crohn's disease (CD) patients and non-CD controls. We performed proximity ligation or a co-immunoprecipitation assay in FOXP3-mutant+, interleukin 6 (IL6)-treated or CD-CD4+ T cells to assess FOXP3-EZH2 protein interaction. We studied IL2 promoter activity and chromatin state of the interferon γ locus via luciferase reporter and chromatin-immunoprecipitation assays, respectively, in cells expressing FOXP3 mutants. Results: EZH2 binding was abrogated by inflammatory bowel disease-associated FOXP3 cysteine 232 (C232) mutation. The C232 mutant showed impaired repression of IL2 and diminished EZH2-mediated trimethylation of histone 3 at lysine 27 on interferon γ, indicative of compromised Treg physiologic function. Generalizing this mechanism, IL6 impaired FOXP3-EZH2 interaction. IL6-induced effects were reversed by Janus kinase 1/2 inhibition. In lamina propria-derived CD4+T cells from CD patients, we observed decreased FOXP3-EZH2 interaction. Conclusions: FOXP3-C232 mutation disrupts EZH2 recruitment and gene co-repressive function. The proinflammatory cytokine IL6 abrogates FOXP3-EZH2 interaction. Studies in lesion-derived CD4+ T cells have shown that reduced FOXP3-EZH2 interaction is a molecular feature of CD patients. Destabilized FOXP3-EZH2 protein interaction via diverse mechanisms and consequent Treg abnormality may drive gastrointestinal inflammation.
Comprehensive Review of Spinal Neurenteric Cysts with a Focus on Histopathological Findings.
Dec 06, 2018   Cureus
Baek WK, Lachkar S, Iwanaga J, Oskouian RJ, Loukas M, Oakes WJ, Tubbs RS
Comprehensive Review of Spinal Neurenteric Cysts with a Focus on Histopathological Findings.
Dec 06, 2018
Cureus
Among the occult spinal dysraphisms, neurenteric cysts (NECs) are rare and are thought to arise due to a failure of the separation of the primitive endoderm and ectoderm. Patients experience various neurological symptoms depending on the location of the lesion. As the epithelial morphology of NECs share similarities with other intracranial and intraspinal cystic growths, the definitive diagnosis of NEC can be made after a histochemical analysis with endodermal markers. Complete resection is associated with the lowest disease recurrence rate.
Cytology of effusions in the coelom cavities.
Nov 30, 2018   Ceskoslovenska Patologie
Dušková J
Cytology of effusions in the coelom cavities.
Nov 30, 2018
Ceskoslovenska Patologie
oelom cavities (pleura, pericardium, peritoneum, tunica vaginalis testis) lined with mesothelial lining derived from the mesoderm, represent a frequent place of propagation of pathological processes both from the neighbourhood and primary. These are most often manifested by effusion, whose cytological examination contributes significantly to the diagnosis. Each larger amount of fluid in the coelom spaces is pathological. The primary task is, as a rule, the identification of tumour cells, more often of metastatic origin (with decreasing frequency (adenocarcinomas, melanoma, sarcomas) than primary (mesothelioma, primary lymphomas of coelom cavities). The differentiation of carcinoma or other tumour populations from mesothelial cells often requires, following careful morphological evaluation, the indication of complementary methods of staining, immunocytochemistry (in haematological malignancies, preferably in combination with flow cytometry) or methods of molecular pathology. Standardization is not yet advanced in this diagnostic area, however there is a consensus for a panel to distinguish between carcinoma and mesothelioma. Diagnosis is always generated via a summation of features. A good outcome requires adequate control of all three phases of the diagnostic process and a clear and unambiguous diagnosis, or differential diagnosis, formulation. Keywords: cytology of effusions - body cavity fluids - coelom cavities - carcinoma - reactive mesothelial cells - mesothelioma.
IVD Development: Nucleus pulposus development and sclerotome specification.
Dec 03, 2018   Current Molecular Biology Reports
Alkhatib B, Ban GI, Williams S, Serra R
IVD Development: Nucleus pulposus development and sclerotome specification.
Dec 03, 2018
Current Molecular Biology Reports
Purpose of review: Intervertebral discs (IVD) are derived from embryonic notochord and sclerotome. The nucleus pulposus is derived from notochord while other connective tissues of the spine are derived from sclerotome. This manuscript will review the past 5 years of research into IVD development. Recent findings: Over the past several years, advances in understanding the step-wise process that govern development of the nucleus pulposus and the annulus fibrosus have been made. Generation of tissues from induced or embryonic stem cells into nucleus pulposus and paraxial mesoderm derived tissues has been accomplished in vitro using pathways identified in normal development. A balance between BMP and TGF-β signaling as well as transcription factors including Pax1/Pax9, Mkx and Nkx3.2 appear to be very important for cell fate decisions generating tissues of the IVD. Summary: Understanding how the IVD develops will provide the foundation for future repair, regeneration, and tissue engineering strategies for IVD disease.

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