Effects of activation of the LINE-1 antisense promoter on the growth of cultured cells

AbstractLong interspersed element 1 (LINE-1, or L1) is a retrotransposon that constitutes ~ 17% of the human genome. Although ~ 6000 full-length L1s spread throughout the human genome, their biological significance remains undetermined. The L1 5′ untranslated region has bidirectional promoter activity with a sense promoter driving L1 mRNA production and an antisense promoter (ASP) driving the production of L1-gene chimeric RNAs. Here, we stimulated L1 ASP activity using CRISPR-Cas9 technology to evaluate its biological impacts. Activation of the L1 ASP upregulated the expression of L1 ASP-driven ORF0 and enhanced cell growth. Furthermore, the exogenous expression of ORF0 also enhanced cell growth. These results indicate that activation of L1 ASP activity fuels cell growth at least through ORF0 expression. To our knowledge, this is the first report demonstrating the role of the L1 ASP in a biological context. Considering that L1 sequences are desilenced in various tumor cells, our results indicate that activation of the L1 ASP may be a cause of tumor growth; therefore, interfering with L1 ASP activity may be a potential strategy to suppress the growth.

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Role of acetylcholinesterase (AChE) secreted by parasitic nematodes on the growth of the cell line from epithelial origin HT29-D4

Parasitology ◽

10.1017/s0031182099004175 ◽

1999 ◽

Vol 118 (5) ◽

pp. 489-498 ◽

Cited By ~ 10

Author(s):

F. HUBY ◽

S. MALLET ◽

H. HOSTE

Keyword(s):

Cell Growth ◽

Cell Line ◽

Polyclonal Antibodies ◽

Polyacrylamide Gel Electrophoresis ◽

Biological Significance ◽

Inhibitory Effect ◽

Parasitic Nematodes ◽

Epithelial Origin

The excretory–secretory (E–S) products of the parasitic nematodes Trichostrongylus colubriformis and Nematodirus battus were found to modify the in vitro proliferation of the tumorous colic HT29-D4 cell line of epithelial origin. A characteristic feature of these E–S products is the presence of a high level of acetylcholinesterase (AChE) activity, the biological significance of which remains unclear. To determine a possible role of AChE on cell growth, the enzyme was purified from E–S products using edrophonium chloride. Purity was confirmed by polyacrylamide gel electrophoresis, using silver and Karnovsky stains, before assessing its effects on cell proliferation. The purified AChE was incorporated at different concentrations in a culture medium of HT29-D4 cells. A mitogenic effect was shown for low concentrations (0·1–14 units). By contrast, an inhibitory effect was noted at high concentrations (35–1400 units). Furthermore, polyclonal antibodies were prepared and depletion of AChE in E–S products by immunoprecipitation or affinity chromatography resulted in a partial or total disappearance of the stimulatory effect of cell growth. Thus, the results from this in vitro study suggest a modulatory role for AChE secreted by nematode parasites on the proliferation of epithelial cells of the host.

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DNA methylation in satellite repeats disorders

Essays in Biochemistry ◽

10.1042/ebc20190028 ◽

2019 ◽

Vol 63 (6) ◽

pp. 757-771 ◽

Cited By ~ 4

Author(s):

Claire Francastel ◽

Frédérique Magdinier

Keyword(s):

Dna Methylation ◽

Human Genome ◽

Repetitive Dna ◽

Dna Sequences ◽

Satellite Repeats ◽

Tremendous Progress ◽

Genes Encoding ◽

Dna Elements ◽

Near Future

Abstract Despite the tremendous progress made in recent years in assembling the human genome, tandemly repeated DNA elements remain poorly characterized. These sequences account for the vast majority of methylated sites in the human genome and their methylated state is necessary for this repetitive DNA to function properly and to maintain genome integrity. Furthermore, recent advances highlight the emerging role of these sequences in regulating the functions of the human genome and its variability during evolution, among individuals, or in disease susceptibility. In addition, a number of inherited rare diseases are directly linked to the alteration of some of these repetitive DNA sequences, either through changes in the organization or size of the tandem repeat arrays or through mutations in genes encoding chromatin modifiers involved in the epigenetic regulation of these elements. Although largely overlooked so far in the functional annotation of the human genome, satellite elements play key roles in its architectural and topological organization. This includes functions as boundary elements delimitating functional domains or assembly of repressive nuclear compartments, with local or distal impact on gene expression. Thus, the consideration of satellite repeats organization and their associated epigenetic landmarks, including DNA methylation (DNAme), will become unavoidable in the near future to fully decipher human phenotypes and associated diseases.

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The role of α2, αv and β1 Integrins in cell growth of hepatocellular carcinoma cells in vitro

Zeitschrift für Gastroenterologie ◽

10.1055/s-0037-1612833 ◽

2018 ◽

Vol 56 (01) ◽

pp. E2-E89

Author(s):

M Juratli ◽

A Schnitzbauer ◽

R Blaheta ◽

W Bechstein

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Growth ◽

Carcinoma Cells ◽

Hepatocellular Carcinoma Cells ◽

Β1 Integrins

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Non-pharmacological Strategies Against Systemic Inflammation: Molecular Basis and Clinical Evidence

Current Pharmaceutical Design ◽

10.2174/1381612826666200403122600 ◽

2020 ◽

Vol 26 (22) ◽

pp. 2620-2629 ◽

Cited By ~ 2

Author(s):

Rita Del Pinto ◽

Davide Pietropaoli ◽

Annalisa Monaco ◽

Giovambattista Desideri ◽

Claudio Ferri ◽

...

Keyword(s):

Human Genome ◽

Systemic Inflammation ◽

Clinical Evidence ◽

Metabolic Diseases ◽

Lifestyle Changes ◽

Common Denominator ◽

Active Lifestyle ◽

Systemic Impact ◽

Public Health Strategies

Systemic inflammation is a common denominator to a variety of cardiovascular (CV) and non-CV diseases and relative risk factors, including hypertension and its control, metabolic diseases, rheumatic disorders, and those affecting the gastrointestinal tract. Besides medications, a non-pharmacological approach encompassing lifestyle changes and other complementary measures is mentioned in several updated guidelines on the management of these conditions. We performed an updated narrative review on the mechanisms behind the systemic impact of inflammation and the role of non-pharmacological, complementary measures centered on lowering systemic phlogosis for preserving or restoring a good global health. The central role of genetics in shaping the immune response is discussed in conjunction with that of the microbiome, highlighting the interdependence and mutual influences between the human genome and microbial integrity, diversity, and functions. Several plausible strategies to modulate inflammation and restore balanced crosstalk between the human genome and the microbiome are then recapitulated, including dietary measures, active lifestyle, and other potential approaches to manipulate the resident microbial community. To date, evidence from high-quality human studies is sparse to allow the unconditioned inclusion of understudied, though plausible solutions against inflammation into public health strategies for global wellness. This gap claims further focused, well-designed research targeted at unravelling the mechanisms behind future personalized medicine.

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MiRNA-145 and Its Direct Downstream Targets in Digestive System Cancers: A Promising Therapeutic Target

Current Pharmaceutical Design ◽

10.2174/1381612826666201029095702 ◽

2020 ◽

Vol 26 ◽

Author(s):

Yini Ma ◽

Xiu Cao ◽

Guojuan Shi ◽

Tianlu Shi

Keyword(s):

Digestive System ◽

Target Genes ◽

Malignant Neoplasm ◽

Vital Role ◽

Diagnostic Biomarkers ◽

Cellular Processes ◽

Promising Therapeutic Target ◽

Direct Target ◽

Potential Strategy

: MicroRNAs (miRNAs) play a vital role in the onset and development of many diseases, including cancers. Emerging evidence shows that numerous miRNAs have the potential to be used as diagnostic biomarkers for cancers, and miRNA-based therapy may be a promising therapy for the treatment of malignant neoplasm. MicroRNA-145 (miR-145) has been considered to play certain roles in various cellular processes, such as proliferation, differentiation and apoptosis, via modulating expression of direct target genes. Recent reports show that miR-145 participates in the progression of digestive system cancers, and plays crucial and novel roles for cancer treatment. In this review, we summarize the recent knowledge concerning the function of miR-145 and its direct targets in digestive system cancers. We discuss the potential role of miR-145 as valuable biomarkers for digestive system cancers and how miR-145 regulates these digestive system cancers via different targets to explore the potential strategy of targeting miR-145.

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Change in mutation frequency at a TP53 hotspot during culture of ENU-mutagenised human lymphoblastoid cells

Mutagenesis ◽

10.1093/mutage/gez014 ◽

2019 ◽

Author(s):

Masahiko Watanabe ◽

Masae Toudou ◽

Taeko Uchida ◽

Misato Yoshikawa ◽

Hiroaki Aso ◽

...

Keyword(s):

Cell Culture ◽

Cell Growth ◽

Mutation Frequency ◽

Cultured Cells ◽

Tp53 Gene ◽

Tumour Suppressor Genes ◽

Restriction Sites ◽

Mutation Spectra ◽

Risk Of Cancer ◽

Assay Conditions

Abstract Mutations in oncogenes or tumour suppressor genes cause increases in cell growth capacity. In some cases, fully malignant cancer cells develop after additional mutations occur in initially mutated cells. In such instances, the risk of cancer would increase in response to growth of these initially mutated cells. To ascertain whether such a situation might occur in cultured cells, three independent cultures of human lymphoblastoid GM00130 cells were treated with N-ethyl-N-nitrosourea to induce mutations, and the cells were maintained for 12 weeks. Mutant frequencies and spectra of the cells at the MspI and HaeIII restriction sites located at codons 247–250 of the TP53 gene were examined. Mutant frequencies at both sites in the gene exhibited a declining trend during cell culture and reached background levels after 12 weeks; this was also supported by mutation spectra findings. These results indicate that the mutations detected under our assay conditions are disadvantageous to cell growth.

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Knockout of Ajuba Attenuates the Growth and Migration of Hepatocellular Carcinoma Cells

Cytogenetic and Genome Research ◽

10.1159/000512264 ◽

2020 ◽

Vol 160 (11-12) ◽

pp. 650-658

Author(s):

Yichen Le ◽

Yi He ◽

Meirong Bai ◽

Ying Wang ◽

Jiaxue Wu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Growth ◽

Cancer Progression ◽

Normal Liver ◽

Cell Growth And Migration ◽

And Migration ◽

Hcc Cells

Ajuba has been found to be mutated or aberrantly regulated in several human cancers and plays important roles in cancer progression via different signaling pathways. However, little is known about the role of Ajuba in hepatocellular carcinoma (HCC). Here, we found an upregulation of Ajuba expression in HCC tissues compared with normal liver tissues, while a poor prognosis was observed in HCC patients with high Ajuba expression. Knockout of Ajuba in HCC cells inhibited cell growth in vitro and in vivo, suppressed cell migration, and enhanced the cell apoptosis under stress. Moreover, re-expression of Ajuba in Ajuba-deficient cells could restore the phenotype of Ajuba-deficient cells. In conclusion, these results indicate that Ajuba is upregulated in HCC and promotes cell growth and migration of HCC cells, suggesting that Ajuba could possibly be a new target for HCC diagnosis and treatment.

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Gene knockout revealed the role of gene feoA in cell growth and division of Lactobacillus delbrueckii subsp. bulgaricus

Archives of Microbiology ◽

10.1007/s00203-021-02345-z ◽

2021 ◽

Author(s):

Xue Han ◽

Yuanqiang Tu ◽

Huiying Wu ◽

Lijuan Zhang ◽

Sainan Zhao

Keyword(s):

Cell Growth ◽

Gene Knockout ◽

Lactobacillus Delbrueckii ◽

Lactobacillus Delbrueckii Subsp

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Differential Role of Threonine and Tyrosine Phosphorylation in the Activation and Activity of the Yeast MAPK Slt2

International Journal of Molecular Sciences ◽

10.3390/ijms22031110 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1110

Author(s):

Gema González-Rubio ◽

Ángela Sellers-Moya ◽

Humberto Martín ◽

María Molina

Keyword(s):

Cell Wall ◽

Biological Activity ◽

Biological Significance ◽

Mitogen Activated Protein Kinase ◽

Activation Loop ◽

High Increase ◽

Dual Specificity ◽

Mitogen Activated Protein ◽

Full Activation

The Mitogen-Activated Protein Kinase (MAPK) Slt2 is central to signaling through the yeast Cell Wall Integrity (CWI) pathway. MAPKs are regulated by phosphorylation at both the threonine and tyrosine of the conserved TXY motif within the activation loop (T190/Y192 in Slt2). Since phosphorylation at both sites results in the full activation of MAPKs, signaling through MAPK pathways is monitored with antibodies that detect dually phosphorylated forms. However, most of these antibodies also recognize monophosphorylated species, whose relative abundance and functionality are diverse. By using different phosphospecific antibodies and phosphate-affinity (Phos-tag) analysis on distinct Slt2 mutants, we determined that Y192- and T190-monophosphorylated species coexist with biphosphorylated Slt2, although most of the Slt2 pool remains unphosphorylated following stress. Among the monophosphorylated forms, only T190 exhibited biological activity. Upon stimulation, Slt2 is first phosphorylated at Y192, mainly by the MAPKK Mkk1, and this phosphorylation is important for the subsequent T190 phosphorylation. Similarly, dephosphorylation of Slt2 by the Dual Specificity Phosphatase (DSP) Msg5 is ordered, with dephosphorylation of T190 depending on previous Y192 dephosphorylation. Whereas Y192 phosphorylation enhances the Slt2 catalytic activity, T190 is essential for this activity. The conserved T195 residue is also critical for Slt2 functionality. Mutations that abolish the activity of Slt2 result in a high increase in inactive Y192-monophosphorylated Slt2. The coexistence of different Slt2 phosphoforms with diverse biological significance highlights the importance of the precise detection of the Slt2 phosphorylation status.

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