• Molecular & Cellular Toxicology
• /
• v.4 no.4
• /
• pp.278-284
• /
• 2008

The X-linked inhibitor of apoptosis (XIAP) is a member of a novel family of inhibitors of apoptosis and has several BIR domains (BIR1, BIR2, and BIR3) and a carboxy-terminal RING zinc-finger. Since suppressionof apoptosis is fundamentally important for carcinogenesis and tumor growth, we investigated the expression and function of XIAP in DEN-induced carcinogenesis using rat model. Wistar rats were injected intraperitoneally with DEN at a dose of 50 mg/kg in twice a week for 12 weeks (Group II) and 16 weeks (Group III) followed by the recovery periods, respectively. The evaluation of DEN-induced carcinogenesis carried out the blood, RT-PCR, histopathological and western blot analysis. The level of blood chemistry including GOT/GPT, albumin, and total bilirubin were significantly exchanged comparing to control and Group I/Group II. The expression of albumin and collagen mRNA were significantly exchanged (P<0.05) in both groups. In addition, AFP mRNA expression decreased more after recovery periods than Group II. XIAP was expressed constitutively in normal rat liver as well as DEN-induced Groups I and Group II. In addition, XIAP expression increased more in Group I with 4 weeks recovery periods than Group I. However, XIAP expression shown to increase in Group lI, otherwise, it was decreased in Group II with 10 weeks repair periods. Taken together, these results suggest the alteration of XIAP expression could be involved in hepatocellular carcinogenesis.

• Molecules and Cells
• /
• v.23 no.2
• /
• pp.145-153
• /
• 2007

Elucidation of the roles of circadian associated factors requires a better understanding of the molecular mechanisms of circadian rhythms, control of flowering time through photoperiodic pathways, and photosensory signal transduction. In Arabidopsis, the APRR1 quintet, APRRs 1, 3, 5, 7, and 9, are known as central oscillator genes. Other plants may share the molecular mechanism underlying the circadian rhythm. To identify and characterize these circadian response genes in Brassica crops whose genome was triplicated after divergence from Arabidopsis, we identified B. rapa BAC clones containing these genes by BLAST analysis of B. rapa BAC end sequences against the five corresponding Arabidopsis regions. Subsequent fingerprinting, Southern hybridization, and PCR allowed identification of five BAC clones, one for each of the five circadian-related genes. By draft shotgun sequencing of the BAC clones, we identified the complete gene sequences and cloned the five expressed B. rapa circadian-associated gene members, BrPRRs 1, 3, 5, 7, and 9. Phylogenetic analysis revealed that each BrPRR was orthologous to the corresponding APRR at the sequence level. Northern hybridization revealed that the five genes were transcribed at distinct points in the 24 hour period, and Southern hybridization revealed that they are present in 2, 1, 2, 2, and 1 copies, respectively in the B. rapa genome, which was triplicated and then diploidized during the last 15 million years.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.3
• /
• pp.189-196
• /
• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of wild Korean lespedeza as a forage legume sources. Dry matter(DM) yield of stages, chemical composition and DM digestibility were observed, also DM intake, digestibility and utilization of nitrogen and energy by Korean native goats were determined. Experimental diets include three treatrnents ; mixture grass hay(GS), GS 80% + lespedeza(LA) 20% and GS 60% + LA 40%, respectively. The DM yield of Korean lespedeza(LA) with advancing the growing stage tended to significantly increase(P<0.05). The average DM yield was observed 7,336kg/ha. CP content of LA tended to decrease, but fiber content tended to increase at growing stage advanced(P<0.05). The tannin content of LA was highest in bud stage (54.5mg/g), but tended to decrease at growing stage advanced, lowest in seed ripe stage(26.8mg/g) (P<0.05). With increasing the level of LA supplementation, DM intake by Korean native goats slightly increased, but no differences were observed in all diets. The digestibility of DM, cellular constituents and NDF were slightly lower for GS 100% diets than LA 20% and 40% supplemented diets(P<0.05). Apparently digested N% was not detected significant differences in all diets, but retained N and biological value were higher for LA supplemented diets than for GS 100% diets (P<0.05). Utilization of DE and ME was not detected significant differences in all diets. Above the results, it could be suggested that LA have a potential to provide as forage legume sources considering the DM yield, DM digestibility and nitrogen utilization.

• Journal of Life Science
• /
• v.20 no.1
• /
• pp.27-32
• /
• 2010

Ultraviolet-B (UVB) radiation induces the formation of reactive oxygen species (ROS) and depletes stores of cellular antioxidants. Fucoidan, polysaccharides containing L-fucose and sulfate ester groups, are constituents of brown algae. In this study, the protective effects of fucoidan on UVB-induced oxidative stress in cultured human skin fibroblast HS68 cells were assessed. Pretreatment with fucoidan significantly reduced malondialdehyde (MDA) content in a dose-dependent manner. With fucoidan pretreatment at a dose of $100\;{\mu}g/ml$, the level of intracellular glutathione was increased by 21.5%, compared to UVB irradiation alone. Fucoidan significantly reduced UVB-induced ROS generation by 40.1% and 68.4% at 10 and $100\;{\mu}g/ml$, respectively, compared to UVB irradiation alone. The positive staining rates of senescence-associated $\beta$-galactosidase were reduced by 23.1% and 16.4% with 10 and $100\;{\mu}g/ml$ of fucoidan, compared to UVB irradiation alone. Fucoidan may exert a photoprotective effect against UVB radiation-induced oxidative stress.

• Journal of Life Science
• /
• v.27 no.5
• /
• pp.501-508
• /
• 2017

Bone morphogenetic proteins (BMPs) are multifunctional cytokines that play important roles in a variety of cellular functions. Among BMP family members, BMP2 efficiently promotes osteoblast differentiation through Smad-mediated runt-related transcription factor 2 (Runx2) expression. Several recent studies suggest that BMPs are associated with clock genes, in particular Bmal1. Bmal1 protein heterodimerizes with Clock protein and then induces period 1 (Per1) expression. However, the role of Per1 on osteoblast differentiation remains unclear. In this study, we investigated whether Per1 is involved in osteoblast differentiation. MC3T3-E1 cells were treated with BMP2 for induction of osteoblastic differentiation. Osteogenic maker gene and Per1 mRNA expression were measured using real-time PCR. Interestingly, BMP2 treatment induced Per1 mRNA expression in MC3T3-E1 cells. To further investigate the function of Per1 on osteoblast differentiation, MC3T3-E1 cells were transiently transfected with pCMV-Per1. Per1 overexpression increased Runx2 mRNA and protein levels. Also, mRNA expression and promoter activity of osteocalcin were upregulated by Per1 overexpression. To investigate the effect of interaction between Per1 and osteogenic condition, MC3T3-E1 cells were cultured in osteogenic medium containing ascorbic acid and ${\beta}$-glycerophosphate. Osteogenic medium-induced ALP staining level and mineralization were synergistically increased by overexpression of Per1. Taken together, these results demonstrate that Per1 is a positive regulator of osteoblast differentiation.

• Korean Journal of Food Science and Technology
• /
• v.32 no.3
• /
• pp.726-735
• /
• 2000

This study was conducted to investigate the biological activities of polysaccharide extracted from the fruit body and cultured mycelia of Phellinus linteus IY001. All fractions were extracted by hot water, in the next, Fr. I, Fr. II, Fr. III and Fr. IV were polysaccharide obtained by ethanol precipitation or ultrafiltration. The highest antitumor activity against sarcoma 180 in ICR mice was observed in Fr. III and Fr. IV at the level 85%, but the antitumor activity had no connection with their anticomplementary activity in vitro, it might probably be due to extraction of hot water. All fractions promoted the production of nitric oxide and $TNF-{\alpha}$ in macrophage, addition of Fr. I and Fr. II resulted in production of nitric oxide$3(5.9{\sim}37.6\;{\mu}M)$ and of the $TNF-{\alpha}$ production($8,696.2{\sim}9,420pg/ml)$. All fractions inhibited the lipid peroxidation induced by $AsA/Fe^{2+}$, $ADP/NADPH/Fe^{3+}\;and\;CCl_4/NADPH$ in rat liver microsomes, and Fr. III showed the electron donating ability stronger than tocopherol in assay system using DPPH. From these results, it is suggested that all fractions contain immunoregulatory components which may protect cellular materials from the oxidative damages by their radical scavenging activities.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.3
• /
• pp.275-287
• /
• 2010

Deep caries may induce pulpitis and the pulpal tissue interacts with microbial invasion. The immune response to protect the pulpal tissue can be mediated by cellular signal molecules produced by the pulpal cells. The understanding of these processes is important to find future therapeutic method for the diseased pulp. The pulp tissue from sound teeth was set as control group (n=30) and the pulp tissue from decayed teeth was set as test group (n=30). Total RNA was extracted from the pulp of each group and it was used for cDNA microarray and reverse transcriptase-polymerase chain reaction(RT-PCR). The expression of TGF-${\beta}1$ was studied by immunohistochemistry. The results were as follows: 1. cDNA microarray analysis identified 520 genes with 6-fold or greater difference in expression level with 143 genes more abundant in health and 377 genes more abundant in disease. 2. The RT-PCR analysis was done for randomly selected 14 genes and the results supported the result of cDNA microarray assay. 3. TGF-${\beta}1$ was highly expressed in the carious pulp and it was found in odontoblast by immunohistochemistry. In conclusion, many cytokines were found to be significantly changed their expression in the diseased pulp(/M/>1.6).

• Applied Microscopy
• /
• v.35 no.2
• /
• pp.97-104
• /
• 2005

Plant epidermis consists of relatively unspecialized cells and more specialized cells of various structure and function. Trichomes are specialized cells originated from the epidermis and much attention has been paid to the plants developing trichomes with peculiar structure and function. The present study has been undertaken to examine the trichome type noticed in the leaf epidermis of Althaea rosea using scanning electron microscopy. Four types, namely simple, short-and long-tufted, and glandular hairs, were detected in their epidermis. Their Distribution, frequency and structure varied by the development and epidermal surface. The most frequently distinguished type was the tufted ones growing in young leaves of the abaxial epidermis, while the simple hairs were rare throught the examination. The short-tufted hairs branched up to seven times having each branchlet about $160{\sim}210{\mu}m$ in length at maturity. The long-tufted hairs exhibited up to ten branchlets, where branchlets could reach up to $900{\sim}1,000{\mu}m$ long when fully expanded. Glandular trichome was the peltate type comprising $1{\sim}2$ secretory head cells, 2 stalk cells and a basal cell. The short peltate glandular hairs, usually not exceeding $40{\mu}m$, differentiated more along the areoles in the adaxial epidermis. The function of these trichomes in A. rosea has been still obscure, but it has been speculated that they probably play a role in protection; non-glandular ones possibly providing a defense against insects and secretory glandular type participating in chemical defense. Structural features of these trichomes at cellular level will be discussed in the following study of transmission electron microscopy.

• Korean Journal of Microbiology
• /
• v.46 no.2
• /
• pp.122-126
• /
• 2010

RAD53 functions as an effector kinase of checkpoint pathways in Saccharomyces cerevisiae, which plays a central role to regulate many downstream cellular processes in response to DNA damage. It also involves in transcriptional activation of various genes including RNR genes which encode the key enzyme required for dNTP synthesis. In this study, we identified CYC8 as a suppressor for the hydroxyurea sensitivity of $rad53{\Delta}$ mutation. $Rad53{\Delta}$ mutant transformed with a multi-copy plasmid containing CYC8 showed increased hydroxyurea resistance. In contrast, TUP1 which forms a complex with CYC8 did not function as a suppressor. In the case of mutations, both $cyc8{\Delta}$ and $tup1{\Delta}$ suppressed hydroxyurea sensitivity of $rad53{\Delta}$. Since CYC8 can propagate as a prion in yeast, overexpression of CYC8 induced misfolding of the normal CYC8 proteins, resulting in dominant cyc8-phenotype. Therefore, it is suggested that CYC8 can act as a multi-copy suppressor due to its prion property. It was observed that the levels of RNR transcription were increased in the yeast strains containing either multi-copies of CYC8 gene or $cyc8{\Delta}$ mutation, suggesting that the increased level of RNR will elevate the intracellular pools of dNTPs, which, in turn, suppress the phenotype of $rad53{\Delta}$ mutation.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.1-5
• /
• 2007

The Precesses for leaf development in dicotyledonous plants are surprisingly complex, while the mechanism of controlling and coordinating them is poorly understood. To characterize the fundamental features of the leaf development of Arabidopsis, we first attempted to isolate mutants that alter leaf morphology. Here, leaf morphological mutant of Arabidopsis, lanceolatal (lan1) which has small and narrow leaves have isolated and characterized. To clarify the function of LAN1 in organ development, we characterized lan1-7 mutant using an anatomical and genetic approach. The lan1-7 mutant had reduced size of foliage leaves and reduced dimensions of stems. A reduction both in cell size and in cell number was evident at the cellular level in the lan1 mutant, revealing that LAN1 gene appears to affect cell division at an earlier stage and cell elongation throughout the development of leaf primordia. from the analysis of heterogeneous plant with lan1 mutation and 35S-AG transgenic plant, AG gene is revealed to regulate leaf morphology under the control of 35S promoter. Thus, MADS-box gene was revealed to have some relationship to that of LAN1 gene at certain stage in leaf development processes.