scholarly journals E-Cadherin Inhibits Cell Surface Localization of the Pro-Migratory 5T4 Oncofetal Antigen in Mouse Embryonic Stem Cells

2007 ◽  
Vol 18 (8) ◽  
pp. 2838-2851 ◽  
Author(s):  
Helen L. Spencer ◽  
Angela M. Eastham ◽  
Catherine L.R. Merry ◽  
Thomas D. Southgate ◽  
Flor Perez-Campo ◽  
...  

Epithelial-mesenchymal transition (EMT) events occur during embryonic development and are important for the metastatic spread of epithelial tumors. We show here that spontaneous differentiation of mouse embryonic stem (ES) cells is associated with an E- to N-cadherin switch, up-regulation of E-cadherin repressor molecules (Snail and Slug proteins), gelatinase activity (matrix metalloproteinase [MMP]-2 and -9), and increased cellular motility, all characteristic EMT events. The 5T4 oncofetal antigen, previously shown to be associated with very early ES cell differentiation and altered motility, is also a part of this coordinated process. E- and N-cadherin and 5T4 proteins are independently regulated during ES cell differentiation and are not required for induction of EMT-associated transcripts and proteins, as judged from the study of the respective knockout ES cells. Further, abrogation of E-cadherin–mediated cell–cell contact in undifferentiated ES cells using neutralizing antibody results in a reversible mesenchymal phenotype and actin cytoskeleton rearrangement that is concomitant with translocation of the 5T4 antigen from the cytoplasm to the cell surface in an energy-dependent manner. E-cadherin null ES cells are constitutively cell surface 5T4 positive, and although forced expression of E-cadherin cDNA in these cells is sufficient to restore cell–cell contact, cell surface expression of 5T4 antigen is unchanged. 5T4 and N-cadherin knockout ES cells exhibit significantly decreased motility during EMT, demonstrating a functional role for these proteins in this process. We conclude that E-cadherin protein stabilizes cortical actin cytoskeletal arrangement in ES cells, and this can prevent cell surface localization of the promigratory 5T4 antigen.

1992 ◽  
Vol 116 (4) ◽  
pp. 889-899 ◽  
Author(s):  
D A Wollner ◽  
K A Krzeminski ◽  
W J Nelson

The development of polarized epithelial cells from unpolarized precursor cells follows induction of cell-cell contacts and requires resorting of proteins into different membrane domains. We show that in MDCK cells the distributions of two membrane proteins, Dg-1 and E-cadherin, become restricted to the basal-lateral membrane domain within 8 h of cell-cell contact. During this time, however, 60-80% of newly synthesized Dg-1 and E-cadherin is delivered directly to the forming apical membrane and then rapidly removed, while the remainder is delivered to the basal-lateral membrane and has a longer residence time. Direct delivery of greater than 95% of these proteins from the Golgi complex to the basal-lateral membrane occurs greater than 48 h later. In contrast, we show that two apical proteins are efficiently delivered and restricted to the apical cell surface within 2 h after cell-cell contact. These results provide insight into mechanisms involved in the development of epithelial cell surface polarity, and the establishment of protein sorting pathways in polarized cells.


2011 ◽  
Vol 301 (5) ◽  
pp. H2038-H2049 ◽  
Author(s):  
Carley Glass ◽  
Dinender K. Singla

microRNAs (miRs) have emerged as critical modulators of various physiological processes including stem cell differentiation. Indeed, miR-1 has been reported to play an integral role in the regulation of cardiac muscle progenitor cell differentiation. However, whether overexpression of miR-1 in embryonic stem (ES) cells (miR-1-ES cells) will enhance cardiac myocyte differentiation following transplantation into the infarcted myocardium is unknown. In the present study, myocardial infarction (MI) was produced in C57BL/6 mice by left anterior descending artery ligation. miR-1-ES cells, ES cells, or culture medium (control) was transplanted into the border zone of the infarcted heart, and 2 wk post-MI, cardiac myocyte differentiation, adverse ventricular remodeling, and cardiac function were assessed. We provide evidence demonstrating enhanced cardiac myocyte commitment of transplanted miR-1-ES cells in the mouse infarcted heart as compared with ES cells. Assessment of apoptosis revealed that overexpression of miR-1 in transplanted ES cells protected host myocardium from MI-induced apoptosis through activation of p-AKT and inhibition of caspase-3, phosphatase and tensin homolog, and superoxide production. A significant reduction in interstitial and vascular fibrosis was quantified in miR-1-ES cell and ES cell transplanted groups compared with control MI. However, no statistical significance between miR-1-ES cell and ES cell groups was observed. Finally, mice receiving miR-1-ES cell transplantation post-MI had significantly improved heart function compared with respective controls ( P < 0.05). Our data suggest miR-1 drives cardiac myocyte differentiation from transplanted ES cells and inhibits apoptosis post-MI, ultimately giving rise to enhanced cardiac repair, regeneration, and function.


2018 ◽  
Vol 115 (27) ◽  
pp. E6162-E6171 ◽  
Author(s):  
Yuan Gao ◽  
Haiyun Gan ◽  
Zhenkun Lou ◽  
Zhiguo Zhang

Bivalent chromatin domains containing repressive H3K27me3 and active H3K4me3 modifications are barriers for the expression of lineage-specific genes in ES cells and must be resolved for the transcription induction of these genes during differentiation, a process that remains largely unknown. Here, we show that Asf1a, a histone chaperone involved in nucleosome assembly and disassembly, regulates the resolution of bivalent domains and activation of lineage-specific genes during mouse ES cell differentiation. Deletion of Asf1a does not affect the silencing of pluripotent genes, but compromises the expression of lineage-specific genes during ES cell differentiation. Mechanistically, the Asf1a–histone interaction, but not the role of Asf1a in nucleosome assembly, is required for gene transcription. Asf1a is recruited to several bivalent promoters, partially through association with transcription factors, and mediates nucleosome disassembly during differentiation. We suggest that Asf1a-mediated nucleosome disassembly provides a means for resolution of bivalent domain barriers for induction of lineage-specific genes during differentiation.


Stem Cells ◽  
2009 ◽  
Vol 27 (9) ◽  
pp. 2069-2080 ◽  
Author(s):  
Francesca Soncin ◽  
Lisa Mohamet ◽  
Dominik Eckardt ◽  
Sarah Ritson ◽  
Angela M. Eastham ◽  
...  

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4599-4599
Author(s):  
Taisuke Kanaji ◽  
Takashi Okamura ◽  
Peter J. Newman

Abstract Abstract 4599 Filamin A is a major non-muscle actin binding protein that plays an important role in cross-linking cortical actin filaments into three-dimensional networks. In addition to its role as a cytoskeletal scaffolding molecule, Filamin A is also known to bind more than 30 other proteins, regulating their subcellular location and coordinating their ability to signal. To analyze the role of filamin A in mouse embryonic stem (ES) cell maturation, we generated filamin ALow ES cells by introducing a micro-RNA that specifically downregulates filamin A expression under the control of a cytomegalovirus promoter. Filamin ALow ES cells exhibited a more rounded morphology than did their wild-type filamin ANormal counterparts, and expressed increased levels of the ES cell transcription factor Nanog. In contrast, non-transfected cells in the same culture dish retained normal expression of filamin A, expressed low levels of Nanog, and exhibited a more elongated and spread phenotype characteristic of differentiating cells. Further evidence for a role for filamin A in ES cell differentiation was provided by the observation that withdrawing leukemia inhibitory factor (LIF) to induce ES cell differentiation was accompanied by increased expression of filamin A, a concomitant loss of Nanog expression, and acquisition of a differentiated morphology. Filamin ALow ES cells were able to retain their undifferentiated phenotype, as evaluated by alkaline phosphatase (Alp) activity, in the presence of a 10-fold lower concentration of LIF than was permissive for filamin ANormal ES cells, or following exposure to the differentiating agent, bone morphogenic protein 4 (BMP4). LIF-induced phosphorylation of ERK was decreased in filamin ALow relative to filamin ANormal ES cells, as was BMP-induced phosphorylation of Smad1/5 - two signaling pathways that initiate ES cell differentiation. Finally, embryoid bodies comprised of filamin ALow ES cells were unable to differentiate into CD41+ hematopoietic progenitor cells. Taken together, these data demonstrate that filamin A plays a previously unrecognized, but critical, scaffolding function that support both the LIF - ERK and BMP4 - Smad1/5 signaling pathways leading to ES and hematopoietic cell differentiation. Manipulation of filamin levels might be useful in the future to modulate the differentiation requirements for a variety of clinically-and therapeutically-useful stem cells. Disclosures: Newman: Novo Nordisk: Consultancy; New York Blood Center: Membership on an entity's Board of Directors or advisory committees.


2007 ◽  
Vol 27 (10) ◽  
pp. 3769-3779 ◽  
Author(s):  
Diego Pasini ◽  
Adrian P. Bracken ◽  
Jacob B. Hansen ◽  
Manuela Capillo ◽  
Kristian Helin

ABSTRACT Polycomb group (PcG) proteins form multiprotein complexes, called Polycomb repressive complexes (PRCs). PRC2 contains the PcG proteins EZH2, SUZ12, and EED and represses transcription through methylation of lysine (K) 27 of histone H3 (H3). Suz12 is essential for PRC2 activity and its inactivation results in early lethality of mouse embryos. Here, we demonstrate that Suz12 −/− mouse embryonic stem (ES) cells can be established and expanded in tissue culture. The Suz12 −/− ES cells are characterized by global loss of H3K27 trimethylation (H3K27me3) and higher expression levels of differentiation-specific genes. Moreover, Suz12 −/− ES cells are impaired in proper differentiation, resulting in a lack of repression of ES cell markers as well as activation of differentiation-specific genes. Finally, we demonstrate that the PcGs are actively recruited to several genes during ES cell differentiation, which despite an increase in H3K27me3 levels is not always sufficient to prevent transcriptional activation. In summary, we demonstrate that Suz12 is required for the establishment of specific expression programs required for ES cell differentiation. Furthermore, we provide evidence that PcGs have different mechanisms to regulate transcription during cellular differentiation.


2004 ◽  
Vol 359 (1446) ◽  
pp. 1009-1020 ◽  
Author(s):  
Patricia Murray ◽  
David Edgar

The potential use of pluripotent stem cells for tissue repair or replacement is now well recognized. While the ability of embryonic stem (ES) cells to differentiate into all cells of the body is undisputed, their use is currently restricted by our limited knowledge of the mechanisms controlling their differentiation. This review discusses recent work by ourselves and others investigating the intercellular signalling events that occur within aggregates of mouse ES cells. The work illustrates that the processes of ES cell differentiation, epithelialization and programmed cell death are dependent upon their location within the aggregates and coordinated by the extracellular matrix. Establishment of the mechanisms involved in these events is not only of use for the manipulation of ES cells themselves, but it also throws light on the ways in which differentiation is coordinated during embryogenesis.


Blood ◽  
2003 ◽  
Vol 102 (5) ◽  
pp. 1649-1653 ◽  
Author(s):  
Renée F. de Pooter ◽  
Sarah K. Cho ◽  
James R. Carlyle ◽  
Juan Carlos Zúñiga-Pflücker

AbstractEmbryonic stem (ES) cells can differentiate into most blood cells in vitro, providing a powerful model system to study hematopoiesis. However, ES cell–derived T lymphocytes have not been generated in vitro, and it was unresolved whether such potential is absent or merely difficult to isolate. Because the latter case might result from rapid commitment to non–T-cell fates, we isolated ES cell–derived prehematopoietic precursors for reconstitution of fetal thymic organ cultures. We found a transient Flk1+CD45– subset of these precursors generated T lymphocytes in vitro, and the use of reaggregate thymic organ cultures greatly enhanced reconstitution frequency. These findings reveal that ES cells can exhibit in vitro T-cell potential, but this is restricted to early stages of ES cell differentiation. Moreover, the results support the notion that the thymic microenvironment can induce T-cell differentiation from a subset of prehematopoietic progenitors and suggest deficient migration into intact thymi hindered previous attempts to generate T cells in vitro from ES cell–derived progenitors. These findings demonstrate that a defined subset of ES cells has the potential to generate T cells in vitro and could contribute to greater understanding of the molecular events of hematopoietic induction and T-cell lineage commitment.


Sign in / Sign up

Export Citation Format

Share Document