Publications by authors named "Seong H Bhoo"

It is important to determine the clinical significance of non-human leukocyte antigen (HLA) antibodies and their association with antibody-mediated rejection (ABMR) of kidney allografts. We collected post-transplant sera from 68 ABMR patients, 67 T-cell mediated rejection (TCMR) patients, and 83 control subjects without rejection, and determined the titers of 39 non-HLA antibodies including antibodies for angiotensin II receptor type I and MICA. We compared all these non-HLA antibody titers among the study groups.

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For an enhanced understanding of the biological mechanisms of human disease, it is essential to investigate protein functions. In a previous study, we developed a prediction method of gene ontology (GO) terms by the I-TASSER/COFACTOR result, and we applied this to uPE1 in chromosome 11. Here, to validate the bioinformatics prediction of C11orf52, we utilized affinity purification and mass spectrometry to identify interacting partners of C11orf52.

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Methylation is a common structural modification that can alter and improve the biological activities of natural compounds. -Methyltransferases (OMTs) catalyze the methylation of a wide array of secondary metabolites, including flavonoids, and are potentially useful tools for the biotechnological production of valuable natural products. An gene () was isolated from perilla leaves as a putative flavonoid OMT (FOMT).

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Chalcone synthase (CHS) is a key enzyme in the flavonoid pathway, participating in the production of phenolic phytoalexins. The rice genome contains 31 family genes (s). The molecular characterization of s suggests that and belong in the bona fide CHSs, while the other members are categorized in the non-CHS group of type III polyketide synthases (PKSs).

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Cinnamyl alcohol dehydrogenase (CAD) is involved in the final step of the phenylpropanod pathway, catalyzing the NADPH-dependent reduction of hydroxy-cinnamaldehydes into the corresponding alcohols. The rice genome contains twelve and genes, collectively called s. To elucidate the biochemical function of the s, , , , and , which are highly expressed in rice, were cloned from rice tissues.

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Cinnamoyl-CoA reductase (CCR) is the first committed enzyme in the monolignol pathway for lignin biosynthesis and catalyzes the conversion of hydroxycinnamoyl-CoAs into hydroxycinnamaldehydes. In the rice genome, 33 genes are annotated as and genes, collectively called s. To elucidate the functions of s, their phylogenetic relationships, expression patterns at the transcription levels and biochemical characteristics were thoroughly analyzed.

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Although they are less abundant in nature, methoxyflavonoids have distinct physicochemical and pharmacological properties compared to common nonmethylated flavonoids. Thus, enzymatic conversion and biotransformation using genetically engineered microorganisms of flavonoids have been attempted for the efficient production of methoxyflavonoids. Because of their regiospecificity, more than two flavonoid O-methyltransferases (FOMTs) and enzyme reactions are required to biosynthesize di(or poly)-methoxyflavonoids.

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Light signals recognized by phytochromes are transduced through interactions between down-stream signaling components. Phytochrome-interacting ankyrin repeat protein 2 (PIA2) was found to interact with phytochrome interacting factor 3 (PIF3), a well-known repressor of plant photomorphogenesis in response to phytochrome-mediated light signalling. Both PIA2 and PIF3 are known to be positive regulators of anthocyanin accumulation in Arabidopsis seedlings under far-red conditions.

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Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report.

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Phytochrome A (phyA) is a light labile phytochrome that mediates plant development under red/far-red light condition. Degradation of phyA is initiated by red light-induced phyA-ubiquitin conjugation through the 26S proteasome pathway. The N-terminal of phyA is known to be important in phyA degradation.

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Rice produces a wide array of phytoalexins in response to pathogen attacks and UV-irradiation. Except for the flavonoid sakuranetin, most phytoalexins identified in rice are diterpenoid compounds. Analysis of phenolic-enriched fractions from UV-treated rice leaves showed that several phenolic compounds in addition to sakuranetin accumulated remarkably in rice leaves.

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Bacteriophytochromes (BphP) are phytochrome-like light sensing proteins in bacteria, which use biliverdin as a chromophore. In order to study the biochemical properties of the DrBphP protein, five (2B8, 2C11, 3B2, 3D2, and 3H7) anti-DrBphP monoclonal antibodies were produced through the immunization of mice with purified full-length DrBphP and DrBphN (1-321 amino acid) proteins, and epitope mapping was then carried out. Among the five antibodies, 2B8 and 2C11 preferentially recognized the N-terminal region of BphP whereas 3B2, 3D2, and 3H7 showed preference for the C-terminal region.

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Photoassimilated carbons are converted to sucrose in green plant leaves and distributed to non-phototropic tissues to provide carbon and energy. In photosynthetic sucrose biosynthesis, the chloroplast envelope triose phosphate/phosphate translocator (TPT) and cytosolic fructose-1,6-bisphosphatase (cFBPase) are key components in photosynthetic sucrose biosynthesis. The simultaneous overexpression of TPT and cFBPase was utilized to increase the source capacity of Arabidopsis.

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Physiological functions of sucrose (Suc) transporters (SUTs) localized to the tonoplast in higher plants are poorly understood. We here report the isolation and characterization of a mutation in the rice (Oryza sativa) OsSUT2 gene. Expression of OsSUT2-green fluorescent protein in rice revealed that OsSUT2 localizes to the tonoplast.

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The ankyrin domain is one of the most common protein motifs in eukaryotic proteins. Repeated ankyrin domains are ubiquitous and their mediation of protein-protein interactions is involved in a number of physiological and developmental responses such as the cell cycle, signal transduction and cell differentiation. A novel putative phytochrome-interacting ankyrin repeat protein 2 (PIA2) containing three repeated ankyrin domains was identified in Arabidopsis.

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Phytochrome-like proteins have been recently identified in prokaryotes but their features and functions are not clear. We cloned a gene encoding the phytochrome-like protein (XoBphP) in a pathogenic bacteria, Xanthomonas oryzae pv. oryzae (Xoo) and investigated characteristics of the protein using a recombinant XoBphP.

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Many aspects of plant metabolism that are involved in plant growth and development are influenced by light-regulated diurnal rhythms as well as endogenous clock-regulated circadian rhythms. To identify the rhythmic proteins in rice, periodically grown (12h light/12h dark cycle) seedlings were harvested for three days at six-hour intervals. Continuous dark-adapted plants were also harvested for two days.

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Filoviruses (Ebola and Marburg viruses) cause severe and often fatal haemorrhagic fever in humans and non-human primates. The US Centers for Disease Control identifies Ebola and Marburg viruses as 'category A' pathogens (defined as posing a risk to national security as bioterrorism agents), which has lead to a search for vaccines that could prevent the disease. Because the use of such vaccines would be in the service of public health, the cost of production is an important component of their development.

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In higher plants, the plastidic glucose translocator (pGlcT) is assumed to play a role in the export of starch degradation products, but this has not yet been studied in detail. To elucidate the role of pGlcT in the leaves of Arabidopsis thaliana, we generated single and double mutants lacking three plastidic sugar transporters, pGlcT, the triose-phosphate/phosphate translocator (TPT), and the maltose transporter (MEX1), and analyzed their growth phenotypes, photosynthetic properties and metabolite contents. In contrast to the pglct-1 and pglct-2 single mutants lacking a visible growth phenotype, the double mutants pglct-1/mex1 and tpt-2/mex1 displayed markedly inhibited plant growth.

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Phytochromes enable plants to sense light information and regulate developmental responses. Phytochromes interact with partner proteins to transmit light signals to downstream components for plant development. PIRF1 (phytochrome-interacting ROP guanine-nucleotide exchange factor (RopGEF 1)) functions as a light-signaling switch regulating root development through the activation of ROPs (Rho-like GTPase of plant) in the cytoplasm.

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In an attempt to understand the complex regulatory mechanisms underlying sucrose-induced flavonoid biosynthesis, we examined several Arabidopsis mutants with altered anthocyanin accumulation. We determined that disruption of ethylene signaling results in a dramatic increase in sucrose-induced anthocyanin accumulation. Furthermore, we investigated why the ein2-1 (ethylene insensitive) Arabidopsis mutant accumulates higher levels of anthocyanin in response to sucrose than wild-type Arabidopsis.

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It is important to solubilize acetone-precipitated proteins before isoelectric focusing (IEF) to achieve high resolution 2-DE gels. To resolve the maximum possible number of plant protein spots, we developed an improved solubilization buffer for plant proteins. We demonstrated that the resolution of 2-DE gels increased dramatically as the concentration of Tris-base increased, with maximum solubilization obtained at 200 mM Tris-base (Ly200T).

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Plant phytochromes, molecular light switches that regulate various aspects of plant growth and development, are phosphoproteins that are also known to be autophosphorylating serine/threonine kinases. Although a few protein phosphatases that directly interact with and dephosphorylate phytochromes have been identified, no protein kinase that acts on phytochromes has been reported thus far, and the exact site of phytochrome autophosphorylation has not been identified. In this study, we investigated the functional role of phytochrome autophosphorylation.

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In Arabidopsis, the compartmentation of sugars into vacuoles is known to be facilitated by sugar transporters. However, vacuolar sugar transporters have not been studied in detail in other plant species. To characterize the rice (Oryza sativa) tonoplast monosaccharide transporters, OsTMT1 and OsTMT2, we analysed their subcellular localization using green fluorescent protein (GFP) and expression patterns using reverse-transcription polymerase chain reaction (RT-PCR), performed histochemical beta-glucuronidase (GUS) assay and in situ hybridization analysis, and assessed sugar transport ability using isolated vacuoles.

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