• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.151-158
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• 2010

Camelina sativa L., known as popular names "gold-of-pleasure" or "false flax" is an alternative oilseed crop that can be grown under different climatic and soil conditions. Up to date, however, the genomic information of Camelina has not been studied in detail. Therefore, a cDNA library was constructed and characterized from young leaves. The constructed cDNA library incorporated of 1334 cDNA clones and the size of the insertion fragments average was 736 base pair. We generated a total of 1269 high-quality expressed sequence tags (ESTs) sequences. The result of cluster analysis of EST sequences showed that the number of unigene was 851. According to subsequent analysis, the 476 (55.9%) unigenes were highly homologous to known function genes and the other 375 (44.1%) unigenes were unknown. Remaining 63 (7.4%) unigenes had no homology with any other peptide in NCBI database, indicating that these seemed to be novel genes expressed in leaves of Camelina. The database-matched ESTs were further classified into 17 categories according to their functional annotation. The most abundant of categories were "protein with binding function or cofactor requirement (27%)", "metabolism (11%)", "subcellular localization (11%)", "cellular transport, transport facilities and transport routes (7%)", "energy (6%)", "regulation of metabolism and protein function (6%)". Our result in this study provides an overview of mRNA expression profile and a basal genetic information of Camelina as an oilseed crop.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.50-56
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• 2012

The Wnt/${\beta}$-catenin signaling pathway regulates diverse developmental processes and adult tissue homeostasis. Inappropriate regulation of this pathway has been associated with human diseases, such as cancers, osteoporosis, and Alzheimer's disease. Using a cell-based chemical screening with natural compounds, we discovered silybin, a plant flavonoid isolated from the Silybum marianum, which activated the Wnt/${\beta}$-catenin signaling pathway in a synergy with Wnt3a-conditioned medium (Wnt3a-CM). In the presence of Wnt3a-CM, silybin up-regulated ${\beta}$-catenin response transcription (CRT) in HEK293-FL reporter cells and 3T3-L1 preadipocytes through stabilization of intracellular ${\beta}$-catenin protein. Silybin and Wnt3a-CM synergistically reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated $receptor{\gamma}$ ($PPAR{\gamma}$) and CAATT enhancer-binding protein ${\alpha}$ (C/$EBP{\alpha}$) in 3T3-L1 preadipocytes, accompanied by the activation of Wnt/${\beta}$-catenin signaling pathway. Taken together, our findings indicate that silybin is a small-molecule synergist of the Wnt/${\beta}$-catenin signaling pathway and can be used as a controllable reagent for investigating biological processes that involve the Wnt/${\beta}$-catenin signaling pathway.

• Biomolecules & Therapeutics
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• v.25 no.3
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• pp.266-271
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• 2017

Synthetic cannabinoids are one of most abused new psychoactive substances. The recreational use of abused drug has aroused serious concerns about the consequences of these drugs on infection. However, the effects of synthetic cannabinoid on resistance to tetanus toxin are not fully understood yet. In the present study, we aimed to determine if the administration of synthetic cannabinoids increase the susceptibility to tetanus toxin-induced motor behavioral deficit and functional changes in cerebellar neurons in mice. Furthermore, we measured T lymphocytes marker levels, such as CD8 and CD4 which against tetanus toxin. JWH-210 administration decreased expression levels of T cell activators including cluster of differentiation (CD) $3{\varepsilon}$, $CD3{\gamma}$, CD74p31, and CD74p41. In addition, we demonstrated that JWH-210 induced motor impairment and decrement of vesicle-associated membrane proteins 2 levels in the cerebellum of mice treated with tetanus toxin. Furthermore, cerebellar glutamatergic neuronal homeostasis was hampered by JWH-210 administration, as evidenced by increased glutamate concentration levels in the cerebellum. These results suggest that JWH-210 may increase the vulnerability to tetanus toxin via the regulation of immune function.

• Journal of Life Science
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• v.26 no.7
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• pp.789-795
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• 2016

A lymph node (LN) is one of the secondary lymphoid organs. An LN consists of a complicated 3 dimensional frame structure and several stromal cells. Fibroblastic reticular cells (FRC) are distributed in the T zone for interaction with T cells. FRC secrete homing chemokines such as CCL19 and CCL21. Moreover, FRC play a pivotal role in the production of extracellular matrix (ECM) into LN for ECM reorganization against pathogen infections. However, not much is known about the involvement of the immune reaction of FRC. The present report is for the characterization of FRC on immune response. For this, FRC were positioned in several infected situations such as co-culture with macrophage, lipopolysaccharide (LPS), and TNFα stimulation. When a co-culture between FRC and macrophage was performed, a morphological change in FRC was observed, and empty space between FRCs was created by this change. The soluble ICAM-1 protein level was up-regulated by co-culturing with Raw264.7 and the treatment of the ROCK inhibitor Y27632. The activity of matrix metalloproteinase (MMP) was up-regulated by LPS onto FRC. Furthermore, the inflammatory cytokine TNFα regulated the expression of ECM in FRC by a gene chip assay. Collectively, it suggests that FRC are involved in immune reactions.

• Journal of Life Science
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• v.26 no.2
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• pp.265-274
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• 2016

Toxin-antitoxin (TA) systems are ubiquitous genetic modules that are evolutionally conserved in bacteria and archaea. TA systems composed of an intracellular toxin and its antidote (antitoxin) are currently classified into five types. Commonly, activation of toxins under stress conditions inhibits diverse cellular processes and consequently induces cell death or reversible growth inhibition. These effects of toxins play various physiological roles in such as regulation of gene expression, growth control (stress response), programmed cell arrest, persister cells, programmed cell death, phage protection, stabilization of mobile genetic elements or postsegregational killing of plasmid-free cells. Accordingly, bacterial TA systems are commonly considered as stress-responsive genetic modules. However, molecule screening for activation of toxin in TA system is available as development of antimicrobial agents. In addition, cytotoxic effect induced by toxin is used as effective cloning method with antitoxic effect of antitoxin; consequently cells containing cloning vector inserted a target gene can survive and false-positive transformants are removed. Also, TA system is applicable to efficient single protein production in biotechnology industry because toxins that are site-specific ribonuclease inhibit protein synthesis except for target protein. Furthermore, some TA systems that induce apoptosis in eukaryotic cells such as cancer cells or virus-infected cells would have a wide range of applications in eukaryotes, and it will lead to new ways of treating human disease. In this review, we summarize the current knowledge on bacterial TA systems and their applications.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.63-70
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• 2006

Natural product compounds are the source of numerous therapeutic agents. The marine environment produces natural products from a variety of structural classes exhibiting activity against numerous disease targets including anticancer agents. Among these, pectenotoxin-2 (PTX-2), which was first identified as a cytotoxic entity in marine sponges, which depolymerizes actin filaments, was found to be highly effective and more potent to activate an intrinsic pathway of apoptosis in p53-deficient tumor cells compared to those with functional p53 both in vitro and in vivo. However, the anti-proliferative mechanism of the compound at non-cytotoxic concentrations has not yet been explored. In the current study, we sought to investigate anti-proliferation and apoptosis of PTX-2 against U937 human leukemic cells and its underlying molecular mechanism. Exposure of U937 cells to PTX-2 resulted in growth inhibition and induction of apoptosis in dose- and time-dependent manner as measured by MTT assay, fluorescent microscopy and flow cytometric analysis. The anti-proliferative effect of PTX-2 was associated with a marked increase in the expression of cyclin-dependent kinase p21 (WAF1/CIP1) mRNA which was tumor suppressor p53-independent. The increase in apoptosis was connected with a time-dependent down-regulation of anti-apoptotic Bcl-XL and inhibitor of apoptosis proteins (IAPs) family such as XIAP and cIAP-2. Though additional studies are needed, these findings suggested that PTX-2-induced inhibition of U937 cells was associated with the induction of apoptotic cell death and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of PTX-2.

• Journal of Life Science
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• v.17 no.12
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• pp.1709-1716
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• 2007

The health benefits of garlic (Allium sativum L.) are derived from a wide variety of components and from the different ways it is administered. The known health benefits of garlic include cardiovascular protective effects, stimulation of immune function, reduction of blood glucose level, protection against microbial, viral and fungal infections, as well as anticancer effects. In the present study, it was examined the effects of water extract of A. sativum (WEAS) on the growth of cultured human tumor cells in order to investigate its anti-proliferative mechanism. Treatment of WEAS to tumor cells resulted in the growth inhibition, especially in leukemia cells, which was associated with induction of G2/M arrest of the cell cycle and apoptosis. In order to further explore the critical events leading to apoptosis in WEAS-treated U937 human leukemia cells, the following effects of WEAS on components of the mitochondrial apoptotic pathway were examined: generation of reactive oxygen species (ROS), alteration of the mitochondrial membrane potential (MMP), and the expression changes of Bcl-2 and IAP family proteins. The cytotoxic effect of WEAS was mediated by its induction of apoptosis as characterized by the occurrence of DNA ladders, apoptotic bodies and chromosome condensation in U937 cells. The WEAS-induced apoptosis in U937 cells was correlated with the generation of intracellular ROS, collapse of MMP, activation of caspase-3 and down-regulation of anti-apoptotic proteins. The quenching of ROS generation with antioxidant N-acetyl-L-cysteine conferred significant protection against WEAS-elicited ROS generation, caspase-3 activation, G2/M arrest and apoptosis. In conclusion, the present study reveals that the cellular ROS generation plays a pivotal role in the initiation of WEAS-triggered apoptotic death in U937 cells.

• Journal of Life Science
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• v.22 no.3
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• pp.428-436
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• 2012

Protein phosphorylation is a universal mechanism that regulates cellular activities. The brassinosteroid (BR) signal transduction pathway is a relay of phosphorylation and dephosphorylation cascades. It starts with the BR-induced activation of the membrane receptor kinase brassinosteroid insensitive 1 (BRI1), resulting in the dephosphorylation of transcription factors such as BZR1/BES2 and BZR2/BES1 followed by BR-induced gene expression. Brassinosteroid signal transduction research has progressed rapidly by identifying the phosphorylation/dephosphorylation site(s) of the BR-regulated kinase and phosphatase substrates with a simultaneous pursuit of mutant phenotypes. Autophosphorylation, transphosphorylation, and serine/threonine and tyrosine phosphorylation of the receptor protein kinases BRI1 and BRI1-associated kinase (BAK1) have increased the understanding of the regulatory role of those kinases during physiological and developmental processes in plants. The phosphorylation event initiated by BR is also found in the regulation of receptor-mediated endocytosis and the subsequent degradation of the receptor. However, the basic molecular links of the BR signal transduction pathway are not well understood regarding this phosphorylation/dephosphorylation event. This review summarizes the current state of BR signal transduction research to uncover the phosphorylation/dephosphorylation networks and suggests directions for future research on steroid signal transduction to gain a more comprehensive understanding of the process.

• Molecules and Cells
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• v.28 no.5
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• pp.431-439
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• 2009

Rice Oryza sativa accelerated cell death and resistance 1 (OsACDR1) encodes a putative Raf-like mitogen-activated protein kinase kinase kinase (MAPKKK). We had previously reported upregulation of the OsACDR1 transcript by a range of environmental stimuli involved in eliciting defense-related pathways. Here we apply biochemical, gain and loss-of-function approaches to characterize OsACDR1 function in rice. The OsACDR1 protein showed autophosphorylation and possessed kinase activity. Rice plants overexpressing OsACDR1 exhibited spontaneous hypersensitive response (HR)-like lesions on leaves, upregulation of defense-related marker genes and accumulation of phenolic compounds and secondary metabolites (phytoalexins). These transgenic plants also acquired enhanced resistance to a fungal pathogen (Magnaporthe grisea) and showed inhibition of appressorial penetration on the leaf surface. In contrast, loss-of-function and RNA silenced OsACDR1 rice mutant plants showed downregulation of defense-related marker genes expressions and susceptibility to M. grisea. Furthermore, transient expression of an OsACDR1:GFP fusion protein in rice protoplast and onion epidermal cells revealed its localization to the nucleus. These results indicate that OsACDR1 plays an important role in the positive regulation of disease resistance in rice.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.11-18
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• 2016

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. $\small{D}$-xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of $\small{D}$-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with $\small{D}$-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with $\small{D}$-xylose. These groups were maintained for two weeks. The effects of $\small{D}$-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ${\beta}$-cells were analyzed. RESULTS: In vivo, $\small{D}$-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. $\small{D}$-xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of $\small{D}$-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with $\small{D}$-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, $\small{D}$-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, $\small{D}$-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ${\beta}$-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.