• Journal of Life Science
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• v.26 no.7
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• pp.758-763
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• 2016

Fatty acid transporters are key mediators of skeletal muscle lipid metabolism. Several protein groups have been implicated in cellular long-chain fatty acid uptake or oxidation, including fatty acid transporter proteins (FATPs), the plasma membrane fatty acid-binding protein (FABPpm), and the fatty acid translocase (FAT/CD36). FAT/CD36 is highly expressed in skeletal muscle and known to be regulated by various factors such as exercise and hormones. Insulin-like growth factor-I (IGF-I) is a well-known regulator of skeletal muscle cells. However, it has not been studied whether there is any interaction between IGF-I and FAT/CD36 in skeletal muscle cells. In this study, the effects of IGF-I treatment on FAT/CD36 induction were examined. Differentiated C2C12 cells were treated with 20 ng/ml of IGF-I at different time points. Treatment of C2C12 cells with IGF-I resulted in increased FAT/CD36 mRNA and protein expression. After 24 and 48 hr of IGF-I treatment, FAT/CD36 mRNA increased 89% and 24% respectively. The increase of both proteins returned to the control level after 72 hr of IGF-I treatment, suggesting that the FAT/CD36 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. These results suggest that IGF-I can regulate the expression of FAT/CD36 in skeletal muscle cells. In conclusion, IGF-I induces a rapid transcriptional modification of the FAT/CD36 gene in C2C12 skeletal muscle cells and has modulating effects on fatty acid uptake proteins as well as oxidative proteins.

• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.459-468
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• 2007

Protein microarray or protein chips is potentially powerful tools for analysis of protein-protein interactions. APin cDNA was previously identified and cloned from a rat odontoblast cDNA library. The purpose of this study was to investigate the APin-protein interactions during ameloblast differentiation. Protein microarray was carried with recombinant APin protein and MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein were selected among 74 interacting proteins. Immortalized ameloblast cells (ALCs) were transfected with pCMV-APin construct and U6-APin siRNA construct. After transfection, the expression of the mRNAs for four proteins selected by protein micoarrays were assessed by RT-PCR. The results were as follows: 1. APin expression was increased and decreased markedly after its over-expression and inactivation, respectively. 2. Over-expression of the APin in the ALCs markedly down-regulated the expression of MEF2 and Aurora kinase A, whereas their expression remained unchanged by its inactivation. 3. Expression of BMPR-IB and EF-hand calcium binding protein were markedly increased by the over-expression of the APin in the ALCs, whereas expression of BMPR-IB remained unchanged and expression of EF-hand calcium binding protein was markedly decreased by its inactivation. These results suggest that APin plays an important role in ameloblast differentiation and mineralization by regulating the expression of MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.9-17
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• 2013

Ran is a small GTP-binding protein that binds and subsequently hydrolyzes GTP. The functions of Ran in nuclear transport and mitotic progression are well conserved in plants and animals. In animal cells, stress treatments cause Ran relocalization and slowing of nuclear transport, but the role of Ran proteins in plant cells exposed to stress is still unclear. We have therefore compared Ran genes from three EST libraries construed from different cell types of sweetpotato and the distribution pattern of Ran ESTs differed according to cell type. We further characterized two IbRan genes. IbRan1 is a specific EST to the suspension cells and leaf libraries, and IbRan2 is specific EST to the root library. IbRan1 showed 94.6 % identity with IbRan2 at the amino acid level, but the C-terminal region of IbRan1 differed from that of IbRan2. These two genes showed tissue-specific differential regulation in wounded tissues. Chilling stress induced a similar expression pattern in both IbRan genes in the leaves and petioles, but they were differently regulated in the roots. Hydrogen peroxide treatment highly stimulated IbRan2 mRNA expression in the leaves and petioles, but had no significant effect on IbRan1 gene expression. These results showed that the transcription of these two IbRan genes responds differentially to abiotic stresses and that they are subjected to tissue-specific regulation. Plant Ran-type small G-proteins are a multigenic family, and the characterization of each Ran genes under various environmental stresses will contribute toward our understanding of the distinctive function of each plant Ran isoform.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.101-112
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• 2014

The aim of this study was to evaluate the biological mechanism of orally administered ethanolic extract of fly maggot(EM) on hypocholesterolemic rats fed a high-cholesterol diet. Sprague Dawley male rats were divided into four groups (EM dose control=0, 5.0, 7.0, and 9.0 mg/100 g BW) and were treated for 6 weeks. EM groups revealed a significant reduction in serum triglyceride, total cholesterol, and LDL-C when compared with the control group(p<0.05). HMG-CoA reductase activity in EM groups were lower than those of the control group, but total sterol, neutral sterol, and bile acid excretion were increased in EM groups when compared with the control group(p<0.05). To identify the biological mechanism of EM towards the hypocholesterolemic effect, sterol response element binding proteins (SREBPs) and the peroxisome proliferator-activated receptors ($PPAR{\alpha}$ transcription system were determined in rats fed a high-cholesterol diet. It was discovered that EM suppress the expression of SREBP-$1{\alpha}$ and SREBP-2 mRNA in the liver tissues of high-cholesterol diet fed rats, while simultaneously increasing the expression of $PPAR{\alpha}$ mRNA(p<0.05). This finding indicates that EM may have hypocholesterolemic effects in rats fed a high-cholesterol diet, by regulating cholesterol metabolism-related biochemical parameters and SREBP-$1{\alpha}$ SREPB-2 and $PPAR{\alpha}$gene expression.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.498-504
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• 2014

Allium senescens L. is perennial plant of the Liliaceae family that grows throughout Korea. In this study, we investigated the effect of Allium senescens L. methanol extracts on reactive oxygen species (ROS) production and lipid accumulation during adipogenesis. Our results indicated that 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of Allium senescens L. methanol extracts increased in a dose-dependent manner. Allium senescens L. methanol extracts suppressed ROS production and lipid accumulation during adipogenesis. In addition, Allium senescens L. methanol extracts inhibited the mRNA expression of the pro-oxidant enzyme, such as G6PDH and lead to a reduction in the mRNA levels of the transcription factors, such as sterol regulatory element binding proteins 1c, peroxisome proliferator-activated receptor ${\gamma}$, and CCAAT/enhancer-binding proteins ${\alpha}$. These results indicate that Allium senescens L. methanol extracts inhibit adipogenesis by modulating ROS production associated with ROS-regulating genes and directly down-regulating adipogenic transcription factors.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1551-1558
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• 2008

The mammalian cellular retinoic acid-binding proteins, CRABP-I and CRABP-II, bind retinoic acid which acts as an inducer of differentiation in several biological systems. To investigate a possible role for CRABP-II in bovine adipogenesis, we have cloned bovine CRABP-II cDNA and the coding region for CRABP-I. The predicted amino acid sequences of CRABP-II were highly conserved among several animal species (human, mouse, and rat at 97%, 93%, and 93%, respectively). The expression pattern of bovine CRABP-II was examined in greater details by applying RT-PCR to various bovine tissues. CRABP-II mRNA was expressed in most adipose-containing tissues. Moreover, the expression of CRABP-I and -II mRNA dramatically increased during the differentiation of adipocytes from bovine intramuscular fibroblast-like cells. The effects of retinoic acid on adipocyte differentiation of bovine intramuscular fibroblast-like cells were concentration-dependent. Retinoic acid activated the formation of lipid droplets at a level of 1 nM, whereas inhibition was observed at a level of $1{\mu}M$. CRABP-I gene was up-regulated and CRABP-II gene down-regulated by retinoic acid during adipocyte differentiation. These results suggest that CRABPs may play an important role in the regulation of intracellular retinoic acid concentrations during adipogenesis.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.329-337
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• 1999

Thyroid hormone-induced cellular dysfunctions may be associated with changes in the intracellular $Ca^{2+}$ concentration. The ryanodine receptor, a $Ca^{2+}$ release channel of the SR, is responsible for the rapid release of $Ca^{2+}$ that activates cardiac muscle contraction. In the excitation-contaction coupling cascade, activation of ryanodine receptors is initiated by the activity of sarcolemmal $Ca^{2+}$ channels, the dihydropyridine receptors. In hyperthyroidism left ventricular contractility and relaxation velocity were increased, whereas these parameters were decreased in hypothyroidism. The mechanisms for these changes have been suggested to include alterations in the expression and/or activity levels of various proteins. In the present study, quantitative changes of ryanodine receptors and the dihydropyridine receptors, and the functional consequences of these changes in various thyroid states were investigated. In hyperthyroid hearts, $[^3H]ryanodine$ binding and ryanodine receptor mRNA levels were increased, but protein levels of ryanodine were not changed significantly. However, the above parameters were markedly decreased in hypothyroid hearts. In case of dihydropyridine receptor, there were a significant increase in the mRNA and protein levels, and [3H]nitrendipine binding, whereas no changes were observed in these parameters of hypothyroid hearts. Our findings indicate that hyperthyroidism is associated with increases in ryanodine receptor and dihydropyridine receptor expression levels, which is well correlated with the ryanodine and dihydropyridine binding. Whereas opposite changes occur in ryanodine receptor of the hypothyroid hearts.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.201-209
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• 2019

Mixed lineage leukemia proteins (MLL) are the key histone lysine methyltransferases that regulate expression of diverse genes. Aberrant activation of MLL promotes leukemia as well as solid tumors in humans, highlighting the urgent need for the development of an MLL inhibitor. We screened and isolated MLL1-binding ssRNAs using SELEX (${\underline{S}}ystemic$ ${\underline{E}}volution$ of ${\underline{L}}igands$ by ${\underline{E}}xponential$ enrichment) technology. When sequences in sub-libraries were obtained using next-generation sequencing (NGS), the most enriched aptamers-APT1 and APT2-represented about 30% and 26% of sub-library populations, respectively. Motif analysis of the top 50 sequences provided a highly conserved sequence: 5'-A[A/C][C/G][G/U][U/A]ACAGAGGG[U/A]GG[A/C] GAGUGGGU-3'. APT1, APT2, and APT5 embracing this motif generated secondary structures with similar topological characteristics. We found that APT1 and APT2 have a good binding activity and the analysis using mutated aptamer variants showed that the site information in the central region was critical for binding. In vitro enzyme activity assay showed that APT1 and APT2 had MLL1 inhibitory activity. Three-dimensional structure prediction of APT1-MLL1 complex indicates multiple weak interactions formed between MLL1 SET domain and APT1. Our study confirmed that NGS-assisted SELEX is an efficient tool for aptamer screening and that aptamers could be useful in diagnosis and treatment of MLL1-mediated diseases.

• Animal Bioscience
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• v.34 no.4
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• pp.751-758
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• 2021

Objective: The objectives of this study were to investigate the relationship between the mRNA expression of adipocyte type fatty acid binding protein (A-FABP) and heart type FABP (H-FABP) in Thai native chicken crossbreeds and evaluate the level of exotic inclusion in native chicken that will improve growth while maintaining its relatively low carcass fat. Methods: The fat deposition traits and mRNA expression of A-FABP and H-FABP were evaluated at 6, 8, 10, and 12 weeks of age in 4 chicken breeds (n = 8/breed/wk) (100% Chee breed [CH] [100% Thai native chicken background], CH male and broiler female [Kaimook e-san1; KM1] [50% CH background], broiler male and KM1 female [Kaimook e-san2; KM2] [25% CH background], and broiler [BR]) using abdominal fat (ABF) and muscular tissues. Results: The BR breed was only evaluated at 6 weeks of age. At week 6, the CH breed had a significantly lower A-FABP expression in ABF and intramuscular fat (IF) compared with the other breeds. At 8 to 12 weeks, the KM2 groups showed significant upregulation (p<0.05) of A-FABP in both ABF and IF compared to the CH and KM1 groups. The expression of H-FABP did not follow any consistent pattern in both ABF and IF across the different ages. Conclusion: Some level of crossbreeding CH chickens can be done to improve growth rate while maintaining their low ABF and IF. The expression level of A-FABP correlate with most fat traits. There was no consistency of H-FABP expression across breed. A-FABPs is involved in fat deposition, genetic markers in these genes could be used in marker assisted studies to select against excessive fat accumulation.

• Animal cells and systems
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• v.3 no.3
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• pp.311-317
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• 1999

Prolactin (PRL) was reported to be locally synthesized in many brain areas including the hypothalamus, thalamus (TH) and hippocampus (HIP). In the pituitary lactotrophs, PRL synthesis is dependent upon a pituitary-specific transcription factor, Pit-1. In the present study, we attempted to identify Pit-1 or Pit-1-like protein in brain areas known as the synthetic sites of PRL. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis showed the same Pit-1 transcripts in brain areas such as the medial basal hypothalamus (MBH), preoptic area (POA), TH, and HIP with the Pit-1 transcripts in the anterior pituitary (AP). Electrophoretic mobility shift assay (EMSA) was run with nuclear protein extracts from brain tissues using a double strand oligomer probe containing a putative Pit-1 binding domain. Shifted bands were found in EMSA results with nuclear proteins from MBH, POA, TH and HIP. Specific binding of the Pit-1-like protein was further confirmed by competition with an unlabeled cold probe. Antisense Pit-1 oligodeoxynucleotide (Pit-1 ODN), which was designed to bind to the Pit-1 translation initiation site and block Pit-1 biosynthesis, was used to test Pit-1 dependent brain PRL transcription. Two nmol of Pit-1 ODN was introduced into the lateral ventricle of a 60-day old male rat brain. RNA blot hybridization and in situ hybridization indicated a decrease of PRL mRNA signals by the treatment of Pit-1 ODN. Taken together, the present study suggests that Pit-1 may play an important role in the transcriptional regulation of local PRL synthesis in the brain.