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Oh D.-J.,Jeju Biodiversity Research Institute | Oh B.-S.,South Sea Fisheries Research Institute | Jung M.-M.,Jeju Fisheries Research Institute | Jung Y.-H.,Jeju Biodiversity Research Institute
Mitochondrial DNA | Year: 2010

We cloned and sequenced the complete mitochondrial DNA (mtDNA) of three tilefishes (Branchiostegus albus, Branchiostegus argentatus, and Branchiostegus japonicus) to characterize and compare their mitochondrial genomes (mitogenomes). The mitogenomes of B. albus, B. argentatus, and B. japonicus were 16,532, 16,550, and 16,541 bp long, respectively, and all consisted of 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA (tRNAs)), which are typical for vertebrate mtDNA. As in other bony fishes, most genes were encoded on the H-strand, except for the nad6 and eight tRNA genes that were encoded on the L-strand. Among the 13 protein-coding genes of all three tilefishes, 2 reading-frame overlaps were found on the same strand: atp8 and atp6 overlapped by 10 nucleotides, and nad4L and nad4 overlapped by 7 nucleotides. The identity of the nad4 gene between B. albus and B. argentatus was the lowest at 87%. Conversely, the identity of the nad6 gene between B. albus and B. japonicus was the highest at 99%. Most tRNA genes were similar in length among the three species, while the tRNA-Ser(AGY) of B. japonicus was 9 bp longer than those of B. albus and B. argentatus. The control region of the mitogenome spanned 853, 862, and 856 bp in B. albus, B. argentatus, and B. japonicus, respectively. A maximum likelihood tree constructed using 11,035 sites contained five independent groups with bootstrap values of 100% in support of their divergence. All three tilefishes examined were clustered with the Pomacanthidae species in Group II. © 2010 Informa UK, Ltd.

Kang S.-M.,Jeju National University | Kim K.-N.,Jeju Biodiversity Research Institute | Lee S.-H.,Jeju National University | Ahn G.,Jeju National University | And 5 more authors.
Carbohydrate Polymers | Year: 2011

Algal fucoidan is a marine sulfated polysaccharide that evidences a variety of biological activities. We assessed the potential activity of the sulfated polysaccharide from Ecklonia cava, on anti-inflammatory activity in LPS-stimulated RAW 264.7 cells. In this study, E. cava was hydrolyzed by five carbohydrases and five proteases. Our findings demonstrated that the AMG extract has the highest yield and exerts the most profound inhibitory effects against NO production. To identify the active compounds, we conducted micro-filtration membrane, ethanol-added separation, and anion exchange and gel permeation chromatography; the purified polysaccharide (PPS) was subsequently obtained. PPS significantly inhibited NO production, prostaglandin-E2 (PGE 2) production and suppressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW 264.7 cells. Thus, PPS inhibited NO and PGE2 production via the inhibition of iNOS and COX-2. These results indicate that the anti-inflammatory activity of PPS may be attributable to the modulation of anti-inflammatory agents. © 2011 Published by Elsevier Ltd. All rights reserved.

Kang S.-M.,Jeju National University | Heo S.-J.,Korea Ocean Research and Development Institute | Kim K.-N.,Jeju Biodiversity Research Institute | Lee S.-H.,Jeju National University | And 3 more authors.
Bioorganic and Medicinal Chemistry | Year: 2012

In this study, the phlorotannin dieckol, which was isolated from the brown alga Ecklonia cava, was examined for its inhibitory effects on melanin synthesis. Tyrosinase inhibitors are important agents for cosmetic products. We therefore examined the inhibitory effects of dieckol on mushroom tyrosinase and melanin synthesis, and analyzed its binding modes using the crystal structure of Bacillus megaterium tyrosinase (PDB ID: 3NM8). Dieckol inhibited mushroom tyrosinase with an IC 50 of 20 μM and was more effective as a cellular tyrosinase having melanin reducing activities than the commercial inhibitor, arbutin, in B16F10 melanoma cells, and without apparent cytotoxicity. It was found that dieckol behaved as a non-competitive inhibitor with l-tyrosine substrates. For further insight, we predicted the 3D structure of tyrosinase and used a docking algorithm to simulate binding between tyrosinase and dieckol. These molecular modeling studies were successful (calculated binding energy value: -126.12 kcal/mol), and indicated that dieckol interacts with His208, Met215, and Gly46. These results suggest that dieckol has great potential to be further developed as a pharmaceutical or cosmetic agent for use in dermatological disorders associated with melanin. © 2011 Elsevier Ltd. All rights reserved.

Pehar M.,University of Wisconsin - Madison | Pehar M.,Medical University of South Carolina | Ko M.H.,University of Wisconsin - Madison | Ko M.H.,Jeju Biodiversity Research Institute | And 4 more authors.
Aging Cell | Year: 2014

p44 is a short isoform of p53 with 'longevity-assurance' activity. Overexpression of p44 in the mouse (p44+/+ transgenic mice) causes a progeroid phenotype that mimics an accelerated form of aging. The phenotype includes abnormal phosphorylation of the microtubule-binding protein tau, synaptic deficits, and cognitive decline. Genetic engineering demonstrated that the phosphorylation status of tau acts upstream of the synaptic deficits. Here, we provide evidence that p44 promotes the phosphorylation of tau in the mouse. Specifically, we show that p44 binds to the promoter of tau kinases Dyrk1A, GSK3β, Cdk5, p35, and p39 and activates their transcription. The upregulation of the above kinases is followed by increased phosphorylation of tau. Finally, we show that p44 is preferentially found in the nucleus and that its levels increase with age in the mouse brain. Taken together, these results suggest that an imbalance in the p53:p44 ratio might be involved with the altered tau metabolism that characterizes aging. © 2014 The Authors. Aging Cell Published by the Anatomical Society and John Wiley & Sons Ltd.

Park S.-Y.,Jeju Biodiversity Research Institute | Lim H.K.,Jeju National University | Lee S.,Jeju National University | Hwang H.C.,Kwangjin BioTech. Inc. | And 2 more authors.
Food Chemistry | Year: 2012

Pepsin-solubilised collagen (PSC) from Red Sea cucumber (Stichopus japonicus) was studied with respect to its wound-healing effects on a human keratinocyte (HaCaT) cell line. Disaggregated collagen fibres were treated with 0.1 M NaOH for 24 h and digested with pepsin for 72 h to reach maximum yield of 26.6%. The results of an in vitro wound-healing test showed that migration of HaCaT cells was 1.5-fold faster on PSC-coated plates than on untreated plates. The migration rate of sea cucumber PSC was similar to that of rat PSC, but five times higher than that of bovine gelatin. HaCaT cells grown on PSC-coated plates revealed increased fibronectin synthesis (6-fold and 3-fold compared to gelatin and rat PSC, respectively). Additionally, sea cucumber PSCs induced HaCaT cell proliferation by decreasing the G1 phase by 5% and maintaining a larger population (8%) of cells in mitosis. Collagen from Red Sea cucumber might be useful as an alternative to mammalian collagen in the nutraceutical and pharmaceutical industries. © 2011 Elsevier Ltd. All rights reserved.

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