XCL100, an inducible nuclear MAP kinase phosphatase from Xenopus laevis: its role in MAP kinase inactivation in differentiated cells and its expression during early development

1995 ◽  
Vol 108 (8) ◽  
pp. 2885-2896 ◽  
Author(s):  
T. Lewis ◽  
L.A. Groom ◽  
A.A. Sneddon ◽  
C. Smythe ◽  
S.M. Keyse
Keyword(s):  
Xenopus Laevis ◽  
Map Kinase ◽  
Early Development ◽  
Nuclear Translocation ◽  
Cell Types ◽  
Differentiated Cells ◽  
Serum Stimulation ◽  
Transient Activation ◽  
Map Kinase Phosphatase

We have cloned the Xenopus laevis homologue (XCL100) of the human CL100 (Thr/Tyr) MAP kinase phosphatase. Expression of the XCL100 mRNA and protein is inducible by serum stimulation and oxidative/heat stress in a X. laevis kidney cell line. In contrast, XCL100 is constitutively expressed in growing Xenopus oocytes. Recombinant XCL100 protein is able to dephosphorylate both tyrosine and threonine residues of activated p42 MAP kinase in vitro and both the Xenopus and human CL100 proteins were localised predominantly in the nucleus in transfected COS-1 cells. As nuclear translocation of activated MAP kinase is necessary for some of its essential functions in proliferation and cell differentiation our results indicate a role for CL100 in the regulation of these nuclear signalling events. In Xenopus kidney cells both heat shock and serum stimulation lead to transient activation of MAP kinase. However, in contrast to results previously reported from studies on mammalian fibroblasts the inactivation of MAP kinase in these epitheloid cells is rapid and is not dependent on synthesis of new protein. These results indicate that the induction of CL100 (or CL100-like enzymes) may not be required for MAP kinase inactivation in all cell types. Finally, during early embryogenesis, levels of XCL100 mRNA are greatly increased at the mid-blastula transition, suggesting that this enzyme may be involved in the regulation of MAP kinase activity during early development.

scholarly journals Histone H3 as a novel substrate for MAP kinase phosphatase-1

2009 ◽  
Vol 296 (2) ◽  
pp. C242-C249 ◽  
Author(s):  
Corttrell M. Kinney ◽  
Unni M. Chandrasekharan ◽  
Lin Yang ◽  
Jianzhong Shen ◽  
Michael Kinter ◽  
...  
Keyword(s):  
Map Kinase ◽  
Map Kinases ◽  
Histone H3 ◽  
Dual Specificity ◽  
Map Kinase Phosphatase ◽  
Mitogen Activated Protein ◽  
And Control ◽  
Interfering Rna ◽  
Endothelial Growth Factor

Mitogen-activated protein (MAP) kinase phosphatase-1 (MKP-1) is a nuclear, dual-specificity phosphatase that has been shown to dephosphorylate MAP kinases. We used a “substrate-trap” technique involving a mutation in MKP-1 of the catalytically critical cysteine to a serine residue (“CS” mutant) to capture novel MKP-1 substrates. We transfected the MKP-1 (CS) mutant and control (wild-type, WT) constructs into phorbol 12-myristate 13-acetate (PMA)-activated COS-1 cells. MKP-1-substrate complexes were immunoprecipitated, which yielded four bands of 17, 15, 14, and 10 kDa with the CS MKP-1 mutant but not the WT MKP-1. The bands were identified by mass spectrometry as histones H3, H2B, H2A, and H4, respectively. Histone H3 was phosphorylated, and purified MKP-1 dephosphorylated histone H3 (phospho-Ser-10) in vitro; whereas, histone H3 (phospho-Thr-3) was unaffected. We have previously shown that thrombin and vascular endothelial growth factor (VEGF) upregulated MKP-1 in human endothelial cells (EC). We now show that both thrombin and VEGF caused dephosphorylation of histone H3 (phospho-Ser-10) and histone H3 (phospho-Thr-3) in EC with kinetics consistent with MKP-1 induction. Furthermore, MKP-1-specific small interfering RNA (siRNA) prevented VEGF- and thrombin-induced H3 (phospho-Ser-10) dephosphorylation but had no effect on H3 (phospho-Thr-3 or Thr-11) dephosphorylation. In summary, histone H3 is a novel substrate of MKP-1, and VEGF- and thrombin-induced H3 (phospho-Ser-10) dephosphorylation requires MKP-1. We propose that MKP-1-mediated H3 (phospho-Ser-10) dephosphorylation is a key regulatory step in EC activation by VEGF and thrombin.

MicroRNA Expression in Macrophages-Derived Microvesicles May Contribute to Cellular Survival and Differentiation

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3557-3557
Author(s):  
Noura Ismail ◽  
Clay B. Marsh ◽  
Melissa Hunter
Keyword(s):  
Peripheral Blood ◽  
Cell Types ◽  
Microrna Expression ◽  
Mononuclear Phagocytes ◽  
Blood Monocytes ◽  
Hematopoietic Stem ◽  
Gm Csf ◽  
Differentiated Cells ◽  
Numerous Cell

Abstract Microvesicles (MV) (also know as exosomes) are small membrane-bound vesicles released by numerous cell types that contain proteins, mRNA and microRNA. We found that MV from activated monocytes drove survival and differentiation in naïve cells. We therefore were interested in understanding the content of MV produced by activated mononuclear phagocytes. Purified peripheral blood monocytes were treated in vitro for 24 h with or without the monocyte survival factors, GM-CSF or M-CSF, respectively. Examination of monocytes and macrophages by electron microscopy or culture supernatants by flow cytometry demonstrated that monocytes produced MV, which quantitatively increased upon differentiation. Treatment with GM-CSF resulted in more MV production than M-CSF-treated monocytes. To examine whether MV from differentiated cells induced myeloid maturation, the MV were collected and added to fresh monocytes; only MV derived from GM-CSF treated cells induced differentiation of naïve monocytes into macrophages. We next hypothesized that expression of microRNA contained in the MV modulated differentiation of monocytes. Profiling of MV from GM-CSF and M-CSF derived macrophages revealed only two significantly expressed microRNAs. We found that mir-155 was significantly elevated by two-fold in MV from GM-CSF-treated cells, while mir-340 was significantly increased seven-fold in M-CSF-derived MV. Notably, mir- 223 was the highest expressed microRNA in MV from both GM-CSF and M-CSF-treated cells. Recent data suggest that expression of mir-223 regulates myeloid, granulocytic and osteoclasts differentiation, and has a role in hematopoietic stem cell proliferation. While mir-223 is present in MV from both GM-CSF and M-CSF treated cells, it is possible that the low abundance of MV produce from M-CSF-treated cells resulted in less effective concentration to induce differentiation. In this model, it is also possible that regulation of proteins targeted by the increase in mir-155 and decrease mir-340 in the GM-CSF-derived MV are responsible for myeloid differentiation. Since changes in microRNA expression including mir-223 has been reported in AML, our data suggest that myeloid-derived MV in the peripheral blood containing mir-223 may be altered contributing to leukemogenesis.

scholarly journals Brain Endothelial miR-146a Negatively Modulates T-Cell Adhesion through Repressing Multiple Targets to Inhibit NF-κB Activation

2015 ◽  
Vol 35 (3) ◽  
pp. 412-423 ◽  
Author(s):  
Dongsheng Wu ◽  
Camilla Cerutti ◽  
Miguel A Lopez-Ramirez ◽  
Gareth Pryce ◽  
Josh King-Robson ◽  
...  
Keyword(s):  
T Cells ◽  
Endothelial Cells ◽  
Nuclear Translocation ◽  
Leukocyte Adhesion ◽  
Cell Types ◽  
Nuclear Factor ◽  
Autoimmune Encephalomyelitis ◽  
Activated T Cells ◽  
Cytokine Activation

Pro-inflammatory cytokine-induced activation of nuclear factor, NF-κB has an important role in leukocyte adhesion to, and subsequent migration across, brain endothelial cells (BECs), which is crucial for the development of neuroinflammatory disorders such as multiple sclerosis (MS). In contrast, microRNA-146a (miR-146a) has emerged as an anti-inflammatory molecule by inhibiting NF-κB activity in various cell types, but its effect in BECs during neuroinflammation remains to be evaluated. Here, we show that miR-146a was upregulated in microvessels of MS-active lesions and the spinal cord of mice with experimental autoimmune encephalomyelitis. In vitro, TNFα and IFNγ treatment of human cerebral microvascular endothelial cells (hCMEC/D3) led to upregulation of miR-146a. Brain endothelial overexpression of miR-146a diminished, whereas knockdown of miR-146a augmented cytokine-stimulated adhesion of T cells to hCMEC/D3 cells, nuclear translocation of NF-κB, and expression of adhesion molecules in hCMEC/D3 cells. Furthermore, brain endothelial miR-146a modulates NF-κB activity upon cytokine activation through targeting two novel signaling transducers, RhoA and nuclear factor of activated T cells 5, as well as molecules previously identified, IL-1 receptor-associated kinase 1, and TNF receptor-associated factor 6. We propose brain endothelial miR-146a as an endogenous NF-κB inhibitor in BECs associated with decreased leukocyte adhesion during neuroinflammation.

scholarly journals Defining totipotency using criteria of increasing stringency

2020 ◽  
Author(s):  
Eszter Posfai ◽  
John Paul Schell ◽  
Adrian Janiszewski ◽  
Isidora Rovic ◽  
Alexander Murray ◽  
...  
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Single Cell ◽  
Pluripotent Stem Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
Differentiated Cells ◽  
Totipotent Cell

AbstractTotipotency is the ability of a single cell to give rise to all the differentiated cells that build the conceptus, yet how to capture this property in vitro remains incompletely understood. Defining totipotency relies upon a variety of assays of variable stringency. Here we describe criteria to define totipotency. We illustrate how distinct criteria of increasing stringency can be used to judge totipotency by evaluating candidate totipotent cell types in the mouse, including early blastomeres and expanded or extended pluripotent stem cells. Our data challenge the notion that expanded or extended pluripotent states harbor increased totipotent potential relative to conventional embryonic stem cells under in vivo conditions.

scholarly journals DPre: computational identification of differentiation bias and genes underlying cell type conversions

2019 ◽  
Author(s):  
Simon Steffens ◽  
Xiuling Fu ◽  
Fangfang He ◽  
Yuhao Li ◽  
Isaac A Babarinde ◽  
...  
Keyword(s):  
Ectopic Expression ◽  
Large Cell ◽  
Cell Types ◽  
Supplementary Information ◽  
Computational Techniques ◽  
Cell Type ◽  
Mixed Cell ◽  
Directional Bias ◽  
Differentiated Cells

Abstract Summary Cells are generally resistant to cell type conversions, but can be converted by the application of growth factors, chemical inhibitors and ectopic expression of genes. However, it remains difficult to accurately identify the destination cell type or differentiation bias when these techniques are used to alter cell type. Consequently, there is demand for computational techniques that can help researchers understand both the cell type and differentiation bias. While advanced tools identifying cell types exist for single cell data and the deconvolution of mixed cell populations, the problem of exploring partially differentiated cells of indeterminate transcriptional identity has not been addressed. To fill this gap, we developed driver-predictor, which relies on scoring per gene transcriptional similarity between RNA-Seq datasets to reveal directional bias of differentiation. By comparing against large cell type transcriptome libraries or a desired target expression profile, the tool enables the user to visualize both the changes in transcriptional identity as well as the genes accounting for the cell type changes. This software will be a powerful tool for researchers to explore in vitro experiments that involve cell type conversions. Availability and implementation Source code is open source under the MIT license and is freely available on https://github.com/LoaloaF/DPre. Supplementary information Supplementary data are available at Bioinformatics online.

Stem Cell-Based Personalized Medicine

2012 ◽  
pp. 1855-1866
Author(s):  
Alessandro Prigione
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Personalized Medicine ◽  
Regenerative Medicine ◽  
Cell Types ◽  
Research Field ◽  
Cellular Reprogramming ◽  
Differentiated Cells ◽  
New Therapeutic Approaches

Regenerative medicine is a rapidly evolving research field whose main aims are to provide new therapeutic approaches and to repair or replace injured tissues with functional cells derived from stem cells. In the past few years, research breakthroughs have revolutionized the field by showing that all somatic cells have the potential to re-acquire stem cell-like properties. Thus, it appears possible to generate relevant cell types starting from cells easily obtained from affected individuals. The obtained differentiated cells could eventually serve as in vitro tools for the study of disease-associated mechanisms and for performing customized drug screenings. Moreover, in the context of cellular transplantation, these cells represent the ideal cell source given that they posses the same genetic code and thus will avoid the occurrence of unwanted immune reactions. Overall, this revolutionary technique called cellular reprogramming might provide substantial support for the future development of personalized medicine. In this chapter, I describe the recent advances in the field of stem cell-based regenerative medicine applications. Parkinson’s disease is chosen as a paradigmatic example in which the use of stem cells for study and therapy could have a relevant impact and potentially represent a future cure for this debilitating disorder.

scholarly journals TET-catalyzed 5-hydroxymethylcytosine regulates gene expression in differentiating colonocytes and colon cancer

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Christopher G. Chapman ◽  
Christopher J. Mariani ◽  
Feng Wu ◽  
Katherine Meckel ◽  
Fatma Butun ◽  
...  
Keyword(s):  
Gene Expression ◽  
Colon Cancer ◽  
Regulation Of Gene Expression ◽  
Human Colon ◽  
Cell Types ◽  
Enzymatic Oxidation ◽  
Dna Hydroxymethylation ◽  
Differentiated Cells ◽  
Colon Cancers

Abstract The formation of differentiated cell types from pluripotent progenitors involves epigenetic regulation of gene expression. DNA hydroxymethylation results from the enzymatic oxidation of 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation (TET) 5-mC dioxygenase enzymes. Previous work has mapped changes in 5-mC during differentiation of intestinal stem cells. However, whether or not 5-hmC regulates colonocyte differentiation is unknown. Here we show that 5-hmC regulates gene expression during colonocyte differentiation and controls gene expression in human colon cancers. Genome-wide profiling of 5-hmC during in vitro colonic differentiation demonstrated that 5-hmC is gained at highly expressed and induced genes and is associated with intestinal transcription factor binding sites, including those for HNF4A and CDX2. TET1 induction occurred during differentiation and TET1 knockdown altered gene expression and inhibited barrier formation of colonocytes. We find that the 5-hmC distribution in primary human colonocytes parallels the distribution found in differentiated cells in vitro and that gene-specific 5-hmC changes in human colon cancers are directly correlated with changes in gene expression. Our results support a model in which 5-hmC regulates differentiation of adult human intestine and 5-hmC alterations contribute to the disrupted gene expression in colon cancer.

scholarly journals Differentiation of trophoblast cells from human embryonic stem cells: to be or not to be?

Reproduction ◽  
2014 ◽  
Vol 147 (5) ◽  
pp. D1-D12 ◽  
Author(s):  
R Michael Roberts ◽  
Kyle M Loh ◽  
Mitsuyoshi Amita ◽  
Andreia S Bernardo ◽  
Katsuyuki Adachi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Pluripotent Stem Cells ◽  
Full Range ◽  
Embryonic Stem ◽  
Cell Types ◽  
Embryonic Cells ◽  
Cell Type ◽  
Differentiated Cells ◽  
Developmental Hierarchy

It is imperative to unveil the full range of differentiated cell types into which human pluripotent stem cells (hPSCs) can develop. The need is twofold: it will delimit the therapeutic utility of these stem cells and is necessary to place their position accurately in the developmental hierarchy of lineage potential. Accumulated evidence suggested that hPSC could develop in vitro into an extraembryonic lineage (trophoblast (TB)) that is typically inaccessible to pluripotent embryonic cells during embryogenesis. However, whether these differentiated cells are truly authentic TB has been challenged. In this debate, we present a case for and a case against TB differentiation from hPSCs. By analogy to other differentiation systems, our debate is broadly applicable, as it articulates higher and more challenging standards for judging whether a given cell type has been genuinely produced from hPSC differentiation.

scholarly journals The Tuberculous Granuloma: An Unsuccessful Host Defence Mechanism Providing a Safety Shelter for the Bacteria?

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Mayra Silva Miranda ◽  
Adrien Breiman ◽  
Sophie Allain ◽  
Florence Deknuydt ◽  
Frederic Altare
Keyword(s):  
Cell Types ◽  
Giant Cells ◽  
The Body ◽  
Differentiated Cells ◽  
Latently Infected ◽  
Long Time ◽  
Infectious Stage ◽  
Different Cell Types

One of the main features of the immune response toM. Tuberculosisis the formation of an organized structure called granuloma. It consists mainly in the recruitment at the infectious stage of macrophages, highly differentiated cells such as multinucleated giant cells, epithelioid cells and Foamy cells, all these cells being surrounded by a rim of lymphocytes. Although in the first instance the granuloma acts to constrain the infection, some bacilli can actually survive inside these structures for a long time in a dormant state. For some reasons, which are still unclear, the bacilli will reactivate in 10% of the latently infected individuals, escape the granuloma and spread throughout the body, thus giving rise to clinical disease, and are finally disseminated throughout the environment. In this review we examine the process leading to the formation of the granulomatous structures and the different cell types that have been shown to be part of this inflammatory reaction. We also discuss the differentin vivoandin vitromodels available to study this fascinating immune structure.

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