• Journal of Plant Biology
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• v.27 no.2
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• pp.43-50
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• 1984

Effects of IAA on the elongation and cell wall hlysocidase activities were investigated in excised rape (Brassica napus L. cv. Yongdang) hypocotyl segments. IAA promoted the elongation of rape hypocotyl segments. In rape hypocotyls, the first 10-mm segments from the hook exhibited maximal elongation and the capacity of elongation was gradually decreased with increasing distance of each 10-mm from the hook. A good correlation has been obtained between the magnitude of endogenous growth and the activities of $\alpha$, $\beta$-glucosidase and $\alpha$, $\beta$-galactosidase. However, exogenous application of IAA did not seem to enhance the tissue with IAA resulted in acidification of the incubation medium. From these data, we can conclude that IAA seems to enhance elongation of the tissue segments, at least in part, by releasing hydrogen ion into cell wall, some of which may participate in the cell wall extension process, but does not seem to trigger the activation of $\alpha$, $\beta$-glucosidase and $\alpha$, $\beta$-galactosidase.

• KSBB Journal
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• v.21 no.5
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• pp.366-370
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• 2006

In this research, analysis of UDP-glucose a precursor of ${\beta}$-1,3-glucan by high performance liquid chromatography(HPLC) was established using a reversed phase system. One of key metabolite UDP-glucose was selected and its concentration changes was measured with the change of fermentation conditions. The effects of fermentation conditions with/without nitrogen source for cell growth on ${\beta}$-1,3-glucan production were dependent on the UDP-glucose concentration. The UDP-glucose was synthesized rapidly during cell exponential growth period and maintained high during ${\beta}$-1,3-glucan production period. The UDP-glucose concentration was higher for ${\beta}$-1.3-glucan production fermentor than that for cell growth fermentor. The ${\beta}$-1,3-glucan production was optimal at pH 5.5 and synthesis of ${\beta}$-1,3-glucan was greatest at pH 5.5.

• IMMUNE NETWORK
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• v.9 no.4
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• pp.133-137
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• 2009

We have recently shown that activin A, a member of TGF-$\beta$ superfamily, stimulates mouse B cells to express IgA isotype but other isotypes. In the present study, we further characterized effects of activin A on B cell growth and IgA expression. We found that activin A did not have effect on LPS-stimulated cell viability. In parallel, CFSE staining analysis revealed that activin A did not alter cell division. An increase of IgA secretion by activin A was completely abrogated by anti-activin A Ab but not by anti-TGF$\beta$1 Ab. In the same conditions, no other isotypes are significantly affected by each antibody treatment. Finally, activin A, as similar to TGF-$\beta$1, increased IgA secretion by mesenteric lymph node cells. These results suggest that activin A can specifically stimulate IgA response, independent of TGF-$\beta$ in the gut.

• Molecules and Cells
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• v.42 no.6
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• pp.480-494
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• 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 Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4775-4778
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• 2013

The key signaling networks regulating cancer cell proliferation remain to be defined. The leucine-rich repeat containing G-protein coupled receptor 48 (GPR48) plays an important role in multiple organ development. In the present study, we investigated whether GPR48 functions in cancer cells using MCF-7, HepG2, NCI-N87 and PC-3 cells. We found that GPR48 overexpression promotes while its knockdown using small interfering RNA oligos inhibits cell proliferation. In addition, Wnt/${\beta}$-catenin signaling was activated in cells overexpressing GPR48. Therefore, our results indicated that GPR48 activates Wnt/${\beta}$-catenin signaling to regulate cancer cell proliferation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4907-4911
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• 2013

The key signaling networks regulating glioma cell proliferation remain poorly defined. The leucine-rich repeat containing G-protein coupled receptor 4 (Lgr4) has been implicated in intestinal, gastric, and epidermal cell functions. We investigated whether Lgr4 functions in glioma cells and found that Lgr4 expression was significantly increased in glioma tissues. In addition, Lgr4 overexpression promoted while its knockdown using small interfering RNA oligos inhibited glioma cell proliferation. In addition, Wnt/${\beta}$-catenin signaling was activated in cells overexpressing Lgr4. Therefore, our results revealed that Lgr4 activates Wnt/${\beta}$-catenin signaling to regulate glioma cell proliferation.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.323-331
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• 2005

The objective of the present study was to investigate the effect of $\beta-lapachone$, a quinone obtained from the bark of the lapacho tree (Tabebuia avellanedae) in South America, on the cell growth of human hepatoma (HepG2) and bladder (T24) carcinoma cells. Exposure of cancer cells to $\beta-lapachone$ resulted in growth inhibition, morphological changes and apoptosis in a concentration-dependent manner, which could be proved by MTT assay and flow cytometry analysis. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses revealed that $\beta-lapachone$ did not affect the levels of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21 (WAFl/CIPl) expression. However, the transcriptional factor Sp-l and proliferating cell nuclear antigen (PCNA) protein levels were significantly down-regulated by $\beta-lapachone$ in both cell lines. Moreover, $\beta-lapachone$ treatment caused a dose-dependent inhibition of the expression of telomere regulatory gene products such as human telomere reverse transcriptase (hTERT) and telomerase-associated protein-l (TEP-l). Taken together, these findings suggest that $\beta-lapachone$-induced inhibition of human hepatoma and bladder carcinoma cell proliferation is associated with the induction of apoptotic cell death via modulation of several major growth regulatory gene products, and provide important new insights into the additional mechanisms of the anti-cancer activity of $\beta-lapachone$.

• Molecules and Cells
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• v.41 no.10
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• pp.909-916
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• 2018

In pancreatic ${\beta}$ cells, glucose stimulates the biosynthesis of insulin at transcriptional and post-transcriptional levels. The RNA-binding protein, polypyrimidine tract-binding protein 1 (PTBP1), also named hnRNP I, acts as a critical mediator of insulin biosynthesis through binding to the pyrimidine-rich region in the 3'-untranslated region (UTR) of insulin mRNA. However, the underlying mechanism that regulates its expression in ${\beta}$ cells is unclear. Here, we report that glucose induces the expression of PTBP1 via the insulin receptor (IR) signaling pathway in ${\beta}$ cells. PTBP1 is present in ${\beta}$ cells of both mouse and monkey, where its levels are increased by glucose and insulin, but not by insulin-like growth factor 1. PTBP1 levels in immortalized ${\beta}$ cells established from wild-type (${\beta}IRWT$) mice are higher than levels in ${\beta}$ cells established from IR-null (${\beta}IRKO$) mice, and ectopic re-expression of IR-WT in ${\beta}IRKO$ cells restored PTBP1 levels. However, PTBP1 levels were not altered in ${\beta}IRKO$ cells transfected with IR-3YA, in which the Tyr1158/1162/1163 residues are substituted with Ala. Consistently, treatment with glucose or insulin elevated PTBP1 levels in ${\beta}IRWT$ cells, but not in ${\beta}IRKO$ cells. In addition, silencing Akt significantly lowered PTBP1 levels. Thus, our results identify insulin as a pivotal mediator of glucose-induced PTBP1 expression in pancreatic ${\beta}$ cells.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.376-380
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• 1995

Monocyte adhesion involves specific cell surface receptors, integrins and results in cell differentiation. We have studied expression and regulation of integrin .${\alpha}_5{\beta}_1$ during differntiation of U937 as in vitro model. To determine expression of integrin ${\alpha}_5{\beta}_1$ during differentiation of U937 as in vitro model. To determine expression of integrin ${\alpha}_5{\beta}_1$ genes by RT-PCR (reverse transcription and polymerase chain reaction) method. We determined expression of integrin ${\alpha}_5{\beta}_1$ genes by RT-PCE (reverse transcription and polymerase chain reaction) method. We found that expression of integrin .alpha.5.betha.1 was greatly increased during PMA-induced differentiation of U937 cells and also found that PMA-induced expression of integrin ${\alpha}_5{\beta}_1$ was inhibited by colchicine, microtubule depoly merizing agent. These results indicate that microtubular integrity is associated with expression of integrin. ${\alpha}_5{\beta}_1$ during PMA-induced differentiation of U937 cells.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.136-148
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• 2002

본 연구는 osteoblastic cells에서 estogen 의 생합성을 유도하는 aromatase의 activity에 대한 봉독(蜂毒)작용을 측정하여, 봉독치료시 Arthritis의 진행 억제 및 estogen의 의한 bone formation의 효과여부를 검증하기 위해 실행하였다. 사용된 세포주로는 Osteoblastic phenotype으로 분화가 유도되는 Human leukaemic cell line FLG 29.1 및 the primary first-passage osteoblastic cells (hOB cells)이며, 이들을 각각 배양하고 각각의 RNA를 isolation한 뒤 PCR 증폭을 하였다. Aromatase에 대한 활성인자인 TPA와 TGF-${\beta}1$ 및 봉독을 이용하여 aromatase의 expression 및 activity에 대해 미치는 영향을 측정한 바, aromatase expression은 FLG 29.1 cell와 hoB cells에서, 50nM TPA 24시간 처리, 봉독 2 ~ 4시간 처리와 TGF-${\beta}1$ 3시간 처리로 유도한 결과 TPA와 TGF-${\beta}1$의 경우는 서로 유사하였고, 봉독에서 상대적으로 높게 나타났다. Aromatase activity는 FLG 29.1 cell, hoB cells에서 24시간 incubation한 결과, 모든 실험에서 일정하게 선상증가를 보였다. $5{\mu}{\ell}/m{\ell}$ BV에서 TPA와 TGF-${\beta}1$보다 뚜렷하게 증가하였으며, 0.5mM Bt2-cAMP, 50nM dexametasone처리에서는 유의성이 없었다. Estrogen 생합성을 촉매하는 aromatase activity BV가 처리에서 현저하게 증가하였기에, Rheumatis arthritis의 bone destruction에 대해 BV가 효과적인 역할을 할 것으로 보여진다.