• Fisheries and Aquatic Sciences
• /
• v.9 no.2
• /
• pp.97-100
• /
• 2006

To determine whether the tetracycline resistance genes tet (34), tet (M), and tet (S) can be transferred among bacteria, we used a filter mating experiment allowing intimate cell-cell contact between donor and recipient. The tet(34) gene, conveyed on a chromosome of Vibrio species (No. 6 and SW-42) was not transferred to Escherichia coli JM109, suggesting that it is not transferred among bacterial species. The tet (M) gene was transferred from three Vibrio strains (4-E, SW-18, and SW-38) to E. coli at frequencies of $8.5{\times}10^{-5}\;to\;2.1{\times}10^{-6}$. The tet(S) gene was transferred from Lactococcus garvieae KHS98032 to E. coli at a frequency of $1.8{\times}10^{-6}$. Transconjugated recipients showed increased minimum inhibitory concentrations against oxytetracycline. Although the donors possess the Tn916-Tn1545 transposons, they were not detected in transformed recipients, suggesting that the transfer of tet(M) and tet(S) is mediated by elements or mechanisms. Two ribosomal protect protein genes were also transmissible from marine bacteria to E. coli, suggesting gene hopping among marine, terrestrial, and human environments.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.8
• /
• pp.3959-3962
• /
• 2016

The ten-eleven-translocation-2 (TET2) gene is a novel tumor suppressor gene involved in several hematological malignancies of myeloid and lymphoid origin. Besides loss-of-function mutations and deletions, hypermethylation of the CpG island at the TET2 promoter has been found in human cancers. The TET2 encoded protein regulates DNA methylation. The present study aimed to examine DNA promoter methylation of TET2 in 100 childhood acute lymphoblastic leukemia (ALL) cases and 120 healthy children in southeast Iran. In addition, mRNA expression levels were assessed in 30 new cases of ALL and 32 controls. Our ndings indicated that promoter methylation of TET2 signi cantly increases the risk of ALL (OR=2.60, 95% CI=1.31-5.12, p=0.0060) in comparison with absent methylation. Furthermore, the TET2 gene was signi cantly downregulated in childhood ALL compared to healthy children (p=0.0235). The results revealed that hypermethylation and downregulation of TET2 gene may play a role in predisposition to childhood ALL. Further studies with larger sample sizes and different ethnicities are needed to con rm our ndings.

• Molecules and Cells
• /
• v.38 no.11
• /
• pp.925-935
• /
• 2015

DNA methylation is a well-characterized epigenetic modification that plays central roles in mammalian development, genomic imprinting, X-chromosome inactivation and silencing of retrotransposon elements. Aberrant DNA methylation pattern is a characteristic feature of cancers and associated with abnormal expression of oncogenes, tumor suppressor genes or repair genes. Ten-eleven-translocation (TET) proteins are recently characterized dioxygenases that catalyze progressive oxidation of 5-methylcytosine to produce 5-hydroxymethylcytosine and further oxidized derivatives. These oxidized methylcytosines not only potentiate DNA demethylation but also behave as independent epigenetic modifications per se. The expression or activity of TET proteins and DNA hydroxymethylation are highly dysregulated in a wide range of cancers including hematologic and non-hematologic malignancies, and accumulating evidence points TET proteins as a novel tumor suppressor in cancers. Here we review DNA demethylation-dependent and -independent functions of TET proteins. We also describe diverse TET loss-of-function mutations that are recurrently found in myeloid and lymphoid malignancies and their potential roles in hematopoietic transformation. We discuss consequences of the deficiency of individual Tet genes and potential compensation between different Tet members in mice. Possible mechanisms underlying facilitated oncogenic transformation of TET-deficient hematopoietic cells are also described. Lastly, we address non-mutational mechanisms that lead to suppression or inactivation of TET proteins in cancers. Strategies to restore normal 5mC oxidation status in cancers by targeting TET proteins may provide new avenues to expedite the development of promising anti-cancer agents.

• Fisheries and Aquatic Sciences
• /
• v.12 no.1
• /
• pp.24-28
• /
• 2009

A tetracycline resistant Vibrio parahaemolyticus, capable of growing on TCBS medium containing tetracycline, was isolated from cultivated fishes. A gene responsible for the tetracycline resistance was cloned from chromosomal DNA of the V. parahaemolyticus strain using Escherichia coli KAM3, which lacks major multi-drug efflux pumps (${\Delta}acrB$) as host cells. The nucleotide sequence and homology analysis revealed an open reading frame (ORF) for tetracycline resistance protein (TetB). In order to characterize the antibiotic resistance of TetB originated from the V. parahaemolyticus strain, the gene was sub cloned into plasmid pSTV28. The resulting plasmid was designated as pSTVTetB and transformated into E. coli KAM3. E. coli KAM3 cells harboring the recombinant plasmid pSTVTetB are able to grow on plates containing tetracycline and oxytetracycline but not doxycycline, indicating that the tetB gene confers the tetracycline- and oxytetracycline-resistance to the host cell.

• Journal of Pharmacopuncture
• /
• v.18 no.4
• /
• pp.20-25
• /
• 2015

Objectives: Recently, thread-embedding therapy (TET) has been widely applied in Korean medicine for cosmetic purposes such as reducing skin wrinkles. An inserted thread was reported to have induced continuous stimulation, followed by support for connective tissue regeneration. However, the potential role of TET in hair-growth has not yet been reported. Methods: We designed this study to evaluate whether TET has a hair-growth-promoting effect. C57 black 6 (C57BL/6) mice were divided into three groups: normal saline-treated, minoxidil-treated, and thread-embedded groups. Normal saline or 5% minoxidil was topically sprayed on the dorsal skin of the mice once a day for 16 days. Medical threads were embedded into the dorsal skin of the mice in a single application. Hair growth activity was evaluated by using dermoscopic and microscopic observations. Sections of the dorsal skin were stained with hematoxylin and eosin. Expressions of bromodeoxyuridine (BrdU), proliferating cell nuclear antigen (PCNA), fibroblast growth factor-7 (FGF-7), and fibroblast growth factor-5 (FGF-5) were detected by using immunohistochemical staining. A reverse transcription-polymerase chain reaction (RT-PCR) analysis was adopted to measure the messenger RNA (mRNA) expressions of FGF-7 and FGF-5. Results: TET enhanced anagen development in the hair follicles of C57BL/6 mice. The expressions of BrdU and PCNA, both of which imply active cellular proliferation, were increased by using TET. Moreover, TET increased the expression of FGF-7, an anagen-inducing growth factor, while decreasing the expression of FGF-5, an anagen-cessation growth factor, both at the protein and the mRNA levels. Conclusion: TET enhanced hair re-growth in C57BL/6 mice. TET regulated the expressions of anagen-associated growth factors and activated the proliferation of hair follicular cells in depilated skin lesions. Considering its long-lasting effect, TET may be a good alternative therapeutic for the treatment of alopecia.

• IMMUNE NETWORK
• /
• v.3 no.4
• /
• pp.276-280
• /
• 2003

Background: Peroxidases (Prx) of the peroxiredoxin family reduce hydrogen peroxide and alkyl hydroperoxides to water and alcohol respectively. Hydrogen peroxide is implicated as an intracellular messenger in various cellular responses such as proliferation and differentiation. And Prx I activity is regulated by Cdc-2 mediated phosphorylation. This work was undertaken to investigate the proliferation role of peroxiredoxin III as a member of Prx family in Prx III overexpressed HeLa cell line. Methods: To provide further evidence of proliferation, we selected Prx III stably expressed HeLa Tet-off cell lines. Cell proliferation was examined by using proliferation reagent WST-1 in the presence or absence of doxycycline. Prx III, 2-cys Prx enzymes exist as homodimer. The activation of Prx III heterodimer with induced and endogenous Prx III was examined by immunoprecipitation. Results: Immunoprecipitation analysis of the induced and endogenous Prx III with anti-myc showed that the induced wild type (WT) and dominant negative (DN) Prx III from HeLa Prx III Tet-off stable cell heterodimerized with endogenous Prx III each other. And the expression level of induced Prx III was examined after addition of doxycycline. By 72 hr, the expression level of induced Prx III was diminished gradually and the half-life of the induced wild type Prx III was approximately 17 hr. The proliferation experiment demonstrated that the relative proliferation value of induced and endogenous WT Prx III stable cell has no changes but the DN Prx III induced HeLa Tet-off stable cells were lower than endogenous Prx III. Conclusion: In conclusion, the HeLa dominant negative Prx III Tet-off stable cells were decreased the proliferation.

• Molecules and Cells
• /
• v.42 no.6
• /
• pp.480-494
• /
• 2019

Aggregates of disease-causing proteins dysregulate cellular functions, thereby causing neuronal cell loss in diverse neurodegenerative diseases. Although many in vitro or in vivo studies of protein aggregate inhibitors have been performed, a therapeutic strategy to control aggregate toxicity has not been earnestly pursued, partly due to the limitations of available aggregate models. In this study, we established a tetracycline (Tet)-inducible nuclear aggregate (${\beta}23$) expression model to screen potential lead compounds inhibiting ${\beta}23$-induced toxicity. High-throughput screening identified several natural compounds as nuclear ${\beta}23$ inhibitors, including peucedanocoumarin III (PCIII). Interestingly, PCIII accelerates disaggregation and proteasomal clearance of both nuclear and cytosolic ${\beta}23$ aggregates and protects SH-SY5Y cells from toxicity induced by ${\beta}23$ expression. Of translational relevance, PCIII disassembled fibrils and enhanced clearance of cytosolic and nuclear protein aggregates in cellular models of huntingtin and ${\alpha}$-synuclein aggregation. Moreover, cellular toxicity was diminished with PCIII treatment for polyglutamine (PolyQ)-huntingtin expression and ${\alpha}$-synuclein expression in conjunction with 6-hydroxydopamine (6-OHDA) treatment. Importantly, PCIII not only inhibited ${\alpha}$-synuclein aggregation but also disaggregated preformed ${\alpha}$-synuclein fibrils in vitro. Taken together, our results suggest that a Tet-Off ${\beta}23$ cell model could serve as a robust platform for screening effective lead compounds inhibiting nuclear or cytosolic protein aggregates. Brain-permeable PCIII or its derivatives could be beneficial for eliminating established protein aggregates.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.1
• /
• pp.42-47
• /
• 2005

The possibility of using Moringa oleifera as a ruminant protein supplement was investigated by comparison between nutritive and anti-nutritive value of its different morphological parts with that of conventionally used Leucaena leucocephala leaf meal (LL). Parameters determined were chemical composition, rumen degradable protein (RDP), acid detergent insoluble protein (ADIP), pepsin soluble protein (PESP), non-protein nitrogen (NPN) total soluble protein (TSP) and protein potentially digested in the intestine (PDI). Total phenols (TP) and total extractable tannins (TET) were also evaluated as anti-nutritive factors. In vitro gas production characteristics were measured and organic matter digestibility (OMD) was estimated basing on 24 h-gas production. Crude protein content ranged from 265-308 g/kg DM in M. oleifera leaves (MOL) and seed cake (MOC) respectively. Leucaena leucocephala and Moringa oleifera soft twigs and leaves (MOLSTL) had CP content of 236 and 195 g/kg DM while Moringa oleifera soft twigs alone (MOST) and Moringa oleifera bucks (MOB) had 160, 114 and 69.3 g/kg DM respectively. RDP was highest in (MOC) (181 g/kg DM) followed by (MOL) (177 g/kg DM) and was lowest in MOB (40 g/kg DM). The proportion of the protein that was not available to the animal (ADIP) was (p<0.05) higher in MOL and MOC (72 and 73 g/kg DM) respectively and lowest in LL (29 g/kg DM). The PDI was high in LL (74 g/kg DM) followed by MOC (55 g/kg DM) then MOL (16 g/kg DM). PESP was highest (p<0.05) in MOC followed by MOL then LL (273, 200 and 163 g/kg DM respectively). MOC exhibited highest NPN content (116 g/kg DM) and was lowest in MOB (18 g/kg DM) (p<0.05). Highly (p<0.05) TSP was observed in MOC and MOL (308 and 265 g/kg DM respectively) followed by LL (236 g/kg DM). MOL had negligible TET (20 g/kg DM) when compared with about 70 g/kg DM in LL. Highly (p<0.05) b and a+b values were observed for MOLSTL (602 and 691 g/kg DM respectively) followed by MOL (490 and 538 g/kg DM). Highest c value was observed in MOSTL followed by MOC and MOL (0.064, 0.056 and 0.053 rate/hour) respectively. OMD was highest (p<0.05) for MOSTL followed by MOC and then MOL (579, 579 and 562 g/kg DM respectively). LL exhibited lower (p<0.05) OMD (467 g/kg DM). It was concluded from this study that the high crude protein content in MOL and MOLST could be well utilized by ruminant animals and increase animal performance however, high proportion of unavailable protein to the lower gut of animals and high rumen degradable protein due to negligible tannin content render it a relatively poor protein supplement for ruminants. MOC can be a best alternative protein supplement to leaves and leaves and soft twigs for ruminants.

• The Korean Journal of Zoology
• /
• v.33 no.3
• /
• pp.266-275
• /
• 1990

c-raf protein kinase, a kind of oncogene, is a cytopiasmic serine / threonine-specific protein and is activated by mitogenic or oncogenic signals. The strncture and functions of c-raf protein kinase are considered very similar to those of protein kinase C. Using immunocytochemical approach, the time course of singal transduction of c-raf protein kinase in EC-4 cell was examined with 12-0-tetradecanoylphorbol-13-acetate (TPA) as tumor promotor and plateletderived growth factor (PDGF) as mitogenic factor. Immunoreactive c-raf was initially bound to the perinuclear membrane and then moved into the nucleus. The effect of the long-term treatment with TPA or PDGF was taken place down regulation at different time point. These results indicate that TPA and PDGF give rise to the translocation of c-raf protein kinase through the two different pathways.

• BMB Reports
• /
• v.50 no.1
• /
• pp.49-54
• /
• 2017

Previously, we reported that vitamin C facilitates the CpG demethylation of Foxp3 enhancer in $CD4^+Foxp3^+$ regulatory T cells (Tregs) by enhancing the activity of a DNA demethylase ten-eleven-translocation (Tet). However, it is not clear whether vitamin C affects other helper T cell lineages like T helper type 17 (Th17) cells which are related with Tregs. Here, we show that the expression of interleukin-17A (IL17) increases with the treatment of vitamin C but not with other antioxidants. Interestingly, the upregulation of IL17 was not accompanied by DNA demethylation in Il17 promoter and was independent of Tet enzymes. Rather, vitamin C reduced the trimethylation of histone H3 lysine 9 (H3K9me3) in the regulatory elements of the Il17 locus, and the effects of vitamin C were abrogated by knockdown of jumonji-C domain-containing protein 2 (jmjd2). These results suggest that vitamin C can affect the expression of IL17 by modulating the histone demethylase activity.