Publications by authors named "Sook-Jae Seo"

Apolipophorin-III (apoLp-III), a hemolymph protein that facilitates lipid transport in aqueous media in insects was recently shown to play a role in insect immune activation. Here, we report another novel possible function of apoLp-III in insects. To identify genes affected by apoLp-III expression in larvae, we decreased endogenous apoLp-III mRNA in Hyphantria cunea (Hc) through RNA interference; subsequently, we observed lower levels of antioxidant enzymes, including manganese superoxide dismutase (MnSOD), glutathione S-transferase, and immune proteins.

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Background: Apolipophorin-III (ApoLp-III) is known to play an important role in lipid transport and innate immunity in lepidopteran insects. However, there is no evidence of involvement of ApoLp-IIIs in the immune responses of dipteran insects such as Drosophila and mosquitoes.

Methodology/principal Findings: We report the molecular and functional characterization of An.

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We have determined the complete mitochondrial genome of the yellow-spotted long horned beetle, Psacothea hilaris (Coleoptera: Cerambycidae), an endangered insect species in Korea. The 15,856-bp long P. hilaris mitogenome harbors gene content typical of the animal mitogenome and a gene arrangement identical to the most common type found in insect mitogenomes.

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Enterococcus faecalis (Ef) accounts for most cases of enterococcal bacteremia, which is one of the principal causes of nosocomial bloodstream infections (BSI). Among several virulence factors associated with the pathogenesis of Ef, an extracellular gelatinase (GelE) has been known to be the most common factor, although its virulence mechanisms, especially in association with human BSI, have yet to be demonstrated. In this study, we describe the complement resistance mechanism of Ef mediated by GelE.

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Insect apolipophorin III (apoLp-III) and human apolipoprotein A-I (apoA-I) are major protein constituents of the lipoprotein system that share various properties. In order to compare the anti-oxidant ability of apoLp-III and apoA-I in the lipid-free and lipid-bound state, both proteins were purified and synthesized individually as a palmitoyloleoyl phosphatidylcholine (POPC)-reconstituted high-density lipoprotein (rHDL) using the same molar ratio. In the lipid-bound state, apoLp-III and apoA-I showed good anti-oxidant activities against copper-mediated LDL oxidation.

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Catalase, which is one of the key enzymes of the cellular antioxidant defense system, prevents free hydroxyl radical formation by breaking down hydrogen peroxide into oxygen and water. Here, we show the cloning and characterization of a catalase gene in a coleopteran insect. This gene was isolated by searching the white-spotted flower chafer Protaetia brevitarsis cDNA library, and the gene itself encodes a protein of 505 amino acids in length, named PbCat.

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We isolated Enterococcus faecalis from the body fluids of dead larvae of the greater wax moth, Galleria mellonella. Extracellular gelatinase (GelE) and serine protease (SprE), both of which are considered putative virulence factors of E. faecalis, were purified from the culture supernatant of E.

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Background: Metamorphosis is a complex, highly conserved and strictly regulated development process that involves the programmed cell death of obsolete larval organs. Here we show a novel functional role for the aspartic proteinase cathepsin D during insect metamorphosis.

Results: Cathepsin D of the silkworm Bombyx mori (BmCatD) was ecdysone-induced, differentially and spatially expressed in the larval fat body of the final instar and in the larval gut of pupal stage, and its expression led to programmed cell death.

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Transferrin in insects is known as an iron transporter, an antibiotic agent, a vitellogenin, and a juvenile hormone-regulated protein. We show here a novel functional role for insect transferrin. Stresses, such as iron overload, bacterial or fungal challenge, cold or heat shock, wounding, and H2O2 or paraquat exposure, cause upregulation of the beetle Apriona germari transferrin (AgTf) gene in the fat body and epidermis, and they cause increased AgTf protein levels.

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Two similar full-length cDNAs of biliprotein were isolated and shown to encode the two isoelectric forms of biliverdin-binding proteins (BPs): BP1 and BP2 in Pieris rapae. Sequence analysis of two cDNA clones shows that both BPs contain a 567-bp open reading frame which predicts a 189-amino acid protein and a 15-amino acid signal peptide. The calculated isoelectric points are pI=7.

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The cDNA corresponding to a novel lipocalin was identified from the fall webworm, Hyphantria cunea. This lipocalin cDNA encodes a 194 residue protein with a calculated molecular mass of 23 kDa. Sequence analyses revealed that the 23 kDa lipocalin cDNA is most similar to Drosophila lazarillo, human apolipoprotein D, and Bombyrin.

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Halocidin is an antimicrobial peptide, which is isolated from hemocytes from the tunicate, Halocynthiaaurantium. In this study, we cloned the full-length cDNA of halocidin from pharyngeal tissue, using a combination of RT-PCR and 5'-RACE-PCR. The observed cDNA structure indicated that halocidin is synthesized as a 10.

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Apolipophorin-III (apoLp-III) is a hemolymph protein whose function is to facilitate lipid transport in an aqueous medium. Recently, apoLp-III in Galleria mellonella larvae was shown to play an unexpected role in insect immune activation. We identified the cDNA sequence of Hyphantria cunea apoLp-III by oligonucleotide-primed amplification, and 5'- and 3'-RACE PCR.

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Two hemolymph proteins were isolated from the wax moth, Galleria mellonella, larvae by a two-step procedure consisting of acid extraction and reversed phase (RP)-HPLC. One was an apolipophorin III (apoLp-III) previously characterized as a lipopolysaccharide (LPS) binding protein in the hemolymph of G. mellonella.

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Insect secreted ferritins are composed of subunits, which resemble heavy and light chains of vertebrate cytosolic ferritins. We describe here the cloning, expression and characterization of cDNAs encoding the ferritin heavy-chain homologue (HCH) and light-chain homologue (LCH) from the mulberry longicorn beetle, Apriona germari (Coleoptera, Cerambycidae). The A.

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A cecropin-like antimicrobial peptide, Gm cecropin, was purified from hemolymph of larvae of the wax moth, Galleria mellonella, immunized against E. coli, and its antibacterial activity was examined in a radial diffusion assay. The molecular mass of Gm cecropin was 4,160.

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We have sequenced a cDNA clone encoding a 26-kDa ferritin subunit, which was heavy chain homologue (HCH), in fall webworm, Hyphantria cunea. The HCH cDNA was obtained from the screening of a cDNA library using a PCR product. H.

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Bacillus thuringiensis 656-3, isolated from a soil sample collected at mushroom houses, showed high toxicity to mushroom flies, Lycoriella mali and Coboldia fuscipes. B. thuringiensis 656-3 produced bipyramidal inclusions and reacted with the H antiserum of B.

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Baculovirus occlusion bodies, large proteinaceous structures which contain virions, have recently been engineered to incorporate foreign proteins. The major constituent protein of occlusion bodies from the baculovirus Autographa californica nucleopolyhedrovirus is polyhedrin, and assembly of recombinant occlusion bodies which incorporate a foreign protein depends on an interaction between native polyhedrin and a polyhedrin-foreign protein fusion. This technology has now been applied to the generation of a recombinant baculovirus (ColorBtrus) that produces occlusion bodies incorporating the Bacillus thuringiensis (Bt) insecticidal Cry1Ac toxin protein.

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We identified two splice variants of lipophorin receptor (LpR) gene products specific to the mosquito fat body (AaLpRfb) and ovary (AaLpRov) with respective molecular masses of 99.3 and 128.9 kDa.

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Article Synopsis
  • This text discusses the cloning and characterization of a cDNA for a storage protein called AgeHex from the mulberry longicorn beetle, which consists of 2,160 base pairs and encodes a protein of 720 amino acids.
  • AgeHex shows a significant resemblance to a similar protein in the mealworm beetle, indicating closer evolutionary relationships among certain storage proteins in insects.
  • Analyses confirm that AgeHex is produced specifically in the fat body of the beetle and exists as a single copy in its genome, with further expression validated through various genetic techniques.
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We isolated and sequenced cDNA clones corresponding to two storage proteins (HcSP-1 and HcSP-2) from fall webworm, Hyphantria cunea. The cDNAs for HcSP-1 (2,337 bp) and HcSP-2 (2,572 bp) code for 753 and 747 residue proteins with predicted molecular masses of 88.3 and 88.

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In the present study, the effects of 1-(beta-naphthylmethyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (YS 51), a positional isomer of 1-(alpha-naphthylmethyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (YS 49), on nitric oxide production and inducible nitric oxide synthase (iNOS) mRNA expression were investigated in RAW 264.7 cells, mouse monocyte macrophage, exposed to lipopolysaccharide (LPS) plus interferon (IFN)-gamma. In addition, the effects of YS 51 on vascular reactivity in vitro and ex vivo, iNOS protein expression (rat lung) and survival rate (mice), were also investigated in LPS-treated rodents.

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A total of 50 raw milk samples from Gyeongnam Province of Korea were examined for the incidence of Listeria monocytogenes between July 1998 and August 1998. L. monocytogenes isolated by biochemical test was confirmed by polymerase chain reaction (PCR) with two sets of primers designed from the invasion-associated protein (iap) gene.

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