scholarly journals Overexpression of prothymosin α accelerates proliferation and retards differentiation in HL-60 cells

1998 ◽  
Vol 331 (3) ◽  
pp. 753-761 ◽  
Author(s):  
Pilar RODRÍGUEZ ◽  
Juan E. VIÑUELA ◽  
Leoncio ÁLVAREZ-FERNÁNDEZ ◽  
Montserrat BUCETA ◽  
Anxo VIDAL ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Opposite Effect ◽  
Cellular Proliferation ◽  
Nuclear Protein ◽  
Prothymosin Α ◽  
Mammalian Cell Lines ◽  
Antisense Orientation ◽  
Cell Clones ◽  
Proliferation And Differentiation ◽  
Antisense Construct

Prothymosin α (ProTα) is an acidic nuclear protein the expression of which is related to the proliferation and differentiation processes in mammalian cells. In the present study we have stably transfected HL-60 cells, a biological system that allows the study of both proliferation and differentiation, with recombinant vectors encoding sense and antisense ProTα mRNA. In the HL-60 cell clones overexpressing ProTα we observed an acceleration in the growth rate, whereas expression of the antisense orientation showed the opposite effect. Moreover, cell-cycle analysis demonstrated that the G1-phase was shortened in the cells expressing the sense construct. Before studying how ProTα affects differentiation, we showed that the down-regulation of ProTα gene during differentiation occurs in all mammalian cell lines (HL-60, K562, U937, MEL C88, N2A and PC12) analysed. The biological effect evoked by the induction of the ProTα sense vector was the retardation of cell differentiation, although expression of the antisense construct showed no effect on differentiation. In conclusion, our findings provide evidence that ProTα is directly implicated in cellular proliferation and that the maintenance of high levels of ProTα inside HL-60 cells is incompatible with their ability to differentiate.

Preliminary methylation analysis of prothymosin α genomic sequences

2012 ◽  
Vol 90 (4) ◽  
pp. 596-601 ◽  
Author(s):  
Leoncio Álvarez-Fernández ◽  
Jaime Gómez-Márquez
Keyword(s):  
Cell Lines ◽  
Nuclear Protein ◽  
Methylation Status ◽  
Genomic Sequences ◽  
Cell Type ◽  
Methylation Analysis ◽  
Prothymosin Α ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Peritumoral Tissue

Prothymosin α is a mammalian nuclear protein involved in cell proliferation and differentiation. Here, we carried out the first study of the methylation status of ProTα genomic sequences in cell lines during differentiation as well as in tumoral tissues. We found that there is hypermethylation in all cell lines analyzed with a pattern that is characteristic of each cell type revealing specific genomic reorganizations. The decrease of ProTα mRNA during differentiation was not accompanied by changes in the methylation status. Remarkably, we found that there is hypomethylation in gastrointestinal tumors when compared with the peritumoral tissue. The biological implications of these findings are discussed.

scholarly journals Prothymosin α is a chromatin-remodelling protein in mammalian cells

1998 ◽  
Vol 333 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Jaime GÓMEZ-MÁRQUEZ ◽  
Pilar RODRÍGUEZ
Keyword(s):  
Mammalian Cells ◽  
Nuclear Protein ◽  
Nuclease Activity ◽  
Histone H1 ◽  
Micrococcal Nuclease ◽  
Active Chromatin ◽  
Dna Ladder ◽  
Prothymosin Α ◽  
Histone Octamer ◽  
Dna Fragment

Prothymosin α (ProTα) is an abundant mammalian acidic nuclear protein whose expression is related to cell proliferation. Here we report that in HL-60 cells overexpressing ProTα, the accessibility of micrococcal nuclease to chromatin is strongly increased. In the DNA ladder generated by the nuclease activity, the sizes of the mononucleosome (146 bp, the DNA fragment that is bound to the histone octamer) and its multimers correspond to nucleosomes lacking histone H1. The percentage of histone-H1-depleted chromatin (active chromatin) is also higher in the cells overexpressing ProTα. On the basis of these and previous findings, we propose a biological role for ProTα in the remodelling of chromatin fibres through its interaction with histone H1.

scholarly journals CD21-Mediated Entry and Stable Infection by Epstein-Barr Virus in Canine and Rat Cells

2000 ◽  
Vol 74 (22) ◽  
pp. 10745-10751 ◽  
Author(s):  
Lixin Yang ◽  
Seiji Maruo ◽  
Kenzo Takada
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Epstein Barr Virus ◽  
Nuclear Antigen ◽  
Simultaneous Treatment ◽  
Barr Virus ◽  
Ebv Infection ◽  
Mammalian Cell Lines ◽  
Cell Clones ◽  
Epstein Barr

ABSTRACT We developed an adenovirus vector for transduction of the human CD21 gene (Adv-CD21), the Epstein-Barr virus (EBV)-specific receptor on human B lymphocytes, to overcome the initial barrier of EBV infection in nonprimate mammalian cells. Inoculation of Adv-CD21 followed by exposure to recombinant EBV carrying a selectable marker resulted in the successful entry of EBV into three of seven nonprimate mammalian cell lines as evidenced by expression of EBV-determined nuclear antigen (EBNA). The EBV-susceptible cell lines included rat glioma-derived 9L, rat mammary carcinoma-derived c-SST-2, and canine kidney-derived MDCK. Subsequent selection culture with G418 yielded drug-resistant cell clones. In these cell clones, EBV existed as an episomal form, as evidenced through the Gardella gel technique. Among the known EBV latency-associated gene products, EBV-encoded small RNAs, EBNA1 and transcripts from the BamHI-A rightward reading frame (BARF0), and latent membrane protein 2A were expressed in all EBV-infected cell clones. The viral lytic events could be induced in these cell clones by simultaneous treatment with 12-O-tetradecanoylphorbol-13-acetate andn-butyric acid, but they were abortive, and infectious virus was not produced. These results indicate that once the initial barrier for attachment is overcome artificially, EBV can establish a stable infection in some nonprimate mammalian cells, and they raise the possibility that transgenic animals with the human CD21 gene could provide an animal model for EBV infection.

Evaluation of the nucleopolyhedrovirus of Anticarsia gemmatalis as a vector for gene therapy in mammals

2020 ◽  
Vol 20 ◽  
Author(s):  
Cintia N. Parsza ◽  
Diego L. Mengual Gómez ◽  
Jorge Alejandro Simonin ◽  
Mariano Nicolás Belaich ◽  
Pablo Daniel Ghiringhelli
Keyword(s):  
Gene Therapy ◽  
Mammalian Cells ◽  
Insect Cells ◽  
Autographa Californica ◽  
Anticarsia Gemmatalis ◽  
Agricultural Pests ◽  
Mammalian Cell Lines ◽  
Delivery Vector ◽  
Wide Range ◽  
Insect Pathogens

Background: Baculoviruses are insect pathogens with important biotechnological applications that transcend their use as biological controllers of agricultural pests. One species, Autographa californica multiple nucleopolhyedrovirus (AcMNPV) has been extensively exploited as a molecular platform to produce recombinant proteins and as a delivery vector for genes in mammals, because it can transduce a wide range of mammalian cells and tissues without replicating or producing progeny. Objective/Method: To investigate if the budded virions of Anticarsia gemmatalis multiple nucleopolhyedrovirus (AgMNPV) species has the same ability, the viral genome was modified by homologous recombination into susceptible insect cells to integrate reporter genes and then it was evaluated on mammalian cell lines in comparative form with respect to equivalent viruses derived from AcMNPV. Besides, the replicative capacity of AgMNPV´s virions in mammals was determined. Results: The experiments carried out showed that the recombinant variant of AgMNPV transduces and support the expression of delivered genes but not replicates in mammalian cells. Conclusion: Consequently, this insect pathogen is proposed as an alternative of non-infectious viruses in humans to explore new approaches in gene therapy and other applications based on the use of mammalian cells.

Gene Targeting

1999 ◽  
Keyword(s):  
Homologous Recombination ◽  
Gene Targeting ◽  
Mammalian Cells ◽  
Es Cells ◽  
Practical Approach ◽  
Simple Method ◽  
Mouse Es Cells ◽  
Cell Clones ◽  
Previous Edition ◽  
Pros And Cons

Since the publication of the first edition of Gene Targeting: A Practical Approach in 1993 there have been many advances in gene targeting and this new edition has been thoroughly updated and rewritten to include all the major new techniques. It provides not only tried-and-tested practical protocols but detailed guidance on their use and applications. As with the previous edition Gene Targeting: A Practical Approach 2e concentrates on gene targeting in mouse ES cells, but the techniques described can be easily adapted to applications in tissue culture including those for human cells. The first chapter covers the design of gene targeting vectors for mammalian cells and describes how to distinguish random integrations from homologous recombination. It is followed by a chapter on extending conventional gene targeting manipulations by using site-specific recombination using the Cre-loxP and Flp-FRT systems to produce 'clean' germline mutations and conditionally (in)activating genes. Chapter 3 describes methods for introducing DNA into ES cells for homologous recombination, selection and screening procedures for identifying and recovering targeted cell clones, and a simple method for establishing new ES cell lines. Chapter 4 discusses the pros and cons or aggregation versus blastocyst injection to create chimeras, focusing on the technical aspects of generating aggregation chimeras and then describes some of the uses of chimeras. The next topic covered is gene trap strategies; the structure, components, design, and modification of GT vectors, the various types of GT screens, and the molecular analysis of GT integrations. The final chapter explains the use of classical genetics in gene targeting and phenotype interpretation to create mutations and elucidate gene functions. Gene Targeting: A Practical Approach 2e will therefore be of great value to all researchers studying gene function.

Cytotoxicity Study of Textile Fabrics Impregnated With CuO Nanoparticles in Mammalian Cells

2017 ◽  
Vol 36 (6) ◽  
pp. 478-484 ◽  
Author(s):  
Gagandeep Singh ◽  
James Beddow ◽  
Christopher Mee ◽  
Lidia Maryniak ◽  
Eadaoin M. Joyce ◽  
...  
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Dermal Fibroblast ◽  
Copper Oxide Nanoparticles ◽  
Growth Media ◽  
Indirect Contact ◽  
Cuo Nps ◽  
Mammalian Cell Lines ◽  
Textile Fabrics ◽  
Hdf Cells

Copper and copper compounds have multifunctional properties (antibacterial, antiviral, and antifungal) with promising applications. Copper in its nanoparticle (Cu NPs) forms has been widely used in various industrial and commercial applications. In the current research, the cytotoxic effects of textile fabrics impregnated with copper oxide nanoparticles (CuO NPs) were studied in mammalian cell lines. CuO NPs were impregnated onto textile substrates using 2 different techniques: the sonochemical generation and impregnation of NPs from metal complexes ( insitu) and a “throwing the stones” technology using commercially prepared CuO NPs. The cytotoxicity of these 2 textile fabric types was assayed on human dermal fibroblast (HDF) cells and human hepatocellular carcinoma cells (HepG2) and was evaluated by indirect contact using an MTT assay. The impregnated fabrics were not exposed to the cells, rather their leachates were used to test cytotoxicity. The fabrics were soaked into the growth media for up to 7 days, and the leachates from day 1 and day 7 were incubated with the cell lines for 24 hours prior to the testing. The discharge or leaching from antimicrobial nanomaterials into the surroundings and surface waters is posing a serious environmental threat, which needs to be addressed. Hence, with regard to product safety, it is a good approach to study the fabric leachates rather than the intact material. The results showed that CuO NPs are not toxic to HDF cells. However, cytotoxicity was seen in HepG2 cells with cell viability decreasing by 20% to 25% for all the fabrics after 24 hours.

MAPK Cascades in Cell Growth and Death

Physiology ◽  
1997 ◽  
Vol 12 (6) ◽  
pp. 286-293 ◽  
Author(s):  
JT Neary
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Cellular Proliferation ◽  
Inflammatory Diseases ◽  
Growth Arrest ◽  
Therapeutic Strategies ◽  
Extracellular Signals ◽  
Mapk Cascades ◽  
Proliferation And Differentiation ◽  
Signaling Components

Distinct signal transduction cascades comprised of at least three proteinkinases mediate cellular proliferation and differentiation, growth arrest, and programmed cell death. These cytosolic enzymes relay extracellular signals from cell surface to nucleus, leading to changes in gene expression. Signaling components of these cascades offer new possibilities for therapeutic strategies in tumorigenesis, inflammatory diseases, immunopotentiation, wound healing, and regeneration.

scholarly journals Regulatory links between imprinted genes: evolutionary predictions and consequences

2016 ◽  
Vol 283 (1824) ◽  
pp. 20152760 ◽  
Author(s):  
Manus M. Patten ◽  
Michael Cowley ◽  
Rebecca J. Oakey ◽  
Robert Feil
Keyword(s):  
Gene Networks ◽  
Cellular Proliferation ◽  
Point Of View ◽  
Imprinted Genes ◽  
Imprinted Gene ◽  
Genome Wide ◽  
Proliferation And Differentiation ◽  
Evolutionary View ◽  
In Trans ◽  
Regulatory Effects

Genomic imprinting is essential for development and growth and plays diverse roles in physiology and behaviour. Imprinted genes have traditionally been studied in isolation or in clusters with respect to cis -acting modes of gene regulation, both from a mechanistic and evolutionary point of view. Recent studies in mammals, however, reveal that imprinted genes are often co-regulated and are part of a gene network involved in the control of cellular proliferation and differentiation. Moreover, a subset of imprinted genes acts in trans on the expression of other imprinted genes. Numerous studies have modulated levels of imprinted gene expression to explore phenotypic and gene regulatory consequences. Increasingly, the applied genome-wide approaches highlight how perturbation of one imprinted gene may affect other maternally or paternally expressed genes. Here, we discuss these novel findings and consider evolutionary theories that offer a rationale for such intricate interactions among imprinted genes. An evolutionary view of these trans -regulatory effects provides a novel interpretation of the logic of gene networks within species and has implications for the origin of reproductive isolation between species.

scholarly journals ADP-Ribosylation of Actin by the Clostridium botulinum C2 Toxin in Mammalian Cells Results in Delayed Caspase-Dependent Apoptotic Cell Death

2008 ◽  
Vol 76 (10) ◽  
pp. 4600-4608 ◽  
Author(s):  
Karin Heine ◽  
Sascha Pust ◽  
Stefanie Enzenmüller ◽  
Holger Barth
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Mammalian Cells ◽  
Clostridium Botulinum ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Adp Ribosylation ◽  
Mammalian Cell Lines ◽  
Adp Ribosyltransferase ◽  
C2 Toxin

ABSTRACT The binary C2 toxin from Clostridium botulinum mono-ADP-ribosylates G-actin in the cytosol of eukaryotic cells. This modification leads to depolymerization of actin filaments accompanied by cell rounding within 3 h of incubation but does not immediately induce cell death. Here we investigated the long-term responses of mammalian cell lines (HeLa and Vero) following C2 toxin treatment. Cells stayed round even though the toxin was removed from the medium after its internalization into the cells. No unmodified actin reappeared in the C2 toxin-treated cells within 48 h. Despite actin being completely ADP-ribosylated after about 7 h, no obvious decrease in the overall amount of actin was observed for at least 48 h. Therefore, ADP-ribosylation was not a signal for an accelerated degradation of actin in the tested cell lines. C2 toxin treatment resulted in delayed apoptotic cell death that became detectable about 15 to 24 h after toxin application in a portion of the cells. Poly(ADP)-ribosyltransferase 1 (PARP-1) was cleaved in C2 toxin-treated cells, an indication of caspase 3 activation and a hallmark of apoptosis. Furthermore, specific caspase inhibitors prevented C2 toxin-induced apoptosis, implying that caspases 8 and 9 were activated in C2 toxin-treated cells. C2I, the ADP-ribosyltransferase component of the C2 toxin, remained active in the cytosol for at least 48 h, and no extensive degradation of C2I was observed. From our data, we conclude that the long-lived nature of C2I in the host cell cytosol was essential for the nonreversible cytotoxic effect of C2 toxin, resulting in delayed apoptosis of the tested mammalian cells.

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