• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.56-59
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• 2003

The Salmonella typhimurium cdd gene encoding cytidine deaminase (cyti-dine/2'-deoxycytidine aminohydrolase; EC 3.5.4.5.) was isolated through shotgun clon-ing by complementation of the E. coli odd mutation. By subsequent deletion and sub-cloning from the original 3.7 Kb of EcoRI insert (pSAMI), the precise region of the cdd structural gene is located around the BglII site in the middle part of 1.7 Kb of NruI/PvuI segment. The 1.7 Kb containing odd gene wag subcloned to the pUC18 vector and the nucleotide sequence of the cdd gene was determined. When the putative ribosorne-binding site (Shine-Dalgarno sequence) and initiation codon were predicted to be GAGG at the position 459 and ATG at the position 470, respectively, there was an open reading frame of 885 nucleotides, encoding an 294 amino acid protein. The cdd gene expression in E. coli JF611/pSAMI was amplified about 50 fold compared to that of the wild type. The cdd gene expression was maintained in the stationary phase after rea-ching the peak in the late logarithmic phase.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.26-26
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• 2015

Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

• Research in Plant Disease
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• v.18 no.1
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• pp.35-39
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• 2012

Occurrence of tomato late blight (Phytophthora infestans) has caused significant losses in tomato yield in all over the world. Evaluation of the level of resistance in tomato gene resources for main breeding and initiation of the resistance breeding program are important for control of this disease. Resistant assay of 78 tomato cultivars/lines to late blight in pots and field experiment was carried out under controlled and natural conditions in 2009. All commercial cultivars including 'Legend' were susceptible. However, 10 lines including KNU-2, KNU-6-1, KNU-11, KNU-13, KNU-14-1 lines distributed from University of California, Riverside and L3708, $AV107-4{\times}L3708$, $07-15{\times}L3708$, $BS67{\times}L3708$ lines which have resistant gene Ph-3 and $06-9-62A{\times}06-9-62A$ were highly resistant to late blight. These highly resistant lines can be used as resources of resistance to late blight in a tomato breeding program in future.

• Korean Journal of Breeding Science
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• v.42 no.2
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• pp.139-143
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• 2010

Late blight caused by Phytophthora infestans is historically a serious epidemic disease in potato and tomato cultivations. Accession L3708 (Solanum pimpinellifolium), a new source for late blight resistance was identified in AVRDC, and carries the resistance gene, Ph-3, incompatible to P. infestans race 3. The AFLP markers linked to Ph-3 were previously developed from the L3708 accession (Chunwongse et al. 2002). To facilitate tomato breeding with the Ph-3 gene, an attempt was made to convert AFLP markers to sequence-characterized amplified region (SCAR) markers. Among 6 AFLP markers, only one AFLP marker, L87, was successfully converted to SCAR marker. The resistance-specific 230 bp AFLP fragment was cloned and sequenced, and the PCR primer amplifying a 123 bp fragment was designed. This SCAR marker could discriminate resistant and susceptible individuals with high stringency. The developed SCAR marker could be used for the marker assisted-selection in tomato breeding programs.

• Journal of Integrative Natural Science
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• v.4 no.2
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• pp.113-120
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• 2011

Brassinosteroids (BRs) are plant steroid hormones that play essential roles in growth and development. Mutations in BR-signaling pathways cause defective in growth and development like dwarfism, male sterility, abnormal vascular development and photomorphogenesis. Transition from vegetative to reproductive growth is a critical phase change in the development of a flowering plant. In a screen of activation-tagged Arabidopsis, we identified a mutant named abz126 that displayed longer hypocotyls when grown in the dark on MS media containing brassinazole (Brz), an inhibitor of BRs biosynthesis. We have cloned the mutant locus using adapter ligation PCR walking and identified that a single T-DNA had been integrated into the ninth exon of the GIGANTEA (GI) gene, involved in controling flowering time. This insertion resulted in loss-of-function of the GI gene and caused the following phenotypes: long petioles, tall plant height, many rosette leaves and late flowering. RT-PCR assays on abz126 mutant showed that the T-DNA insertion in GIGANTEA led to the loss of mRNA expression of the GI gene. In the hormone dose response assay, abz126 mutant showed: 1) an insensitivity to paclobutrazole (PAC), 2) an altered response with 6-benzylaminopurine (BAP) and 3) insensitive to Brassinolide (BL). Based on these results, we propose that the late flowering and tall phenotypes displayed by the abz126 mutant are caused by a loss-of-function of the GI gene associated with brassinosteroid hormone signaling.

• Journal of Microbiology
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• v.34 no.3
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• pp.248-254
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• 1996

$cdc103^+$ gene in Schizosaccharomyces pombe which is similar to the CDC3 gene in Saccharomyces cerevisiae was cloned and sequenced. Comparison of the predicted amino acid sequences of $cdc103^+$ and CDC3 revealed that they share significant similarity (43% identity and 56% identity or similarity) to each other. The gene product of CDC3 in S. cerevisiae is known to be a highly ordered ring of filaments that lies just inside the cytoplasmic membrane in the region of the mother-bud neck. In order to characterize the gene product of $cdc103^+$ in Schizosaccharomyces pombe, fusion proteins were used to generate the polyclonal antibodies specific for the gene product (cdc103p). In immunofluorescence experiments, these antibodies decorate the region of the septum formation as a double ring structure late in the cell division cycle.

• Clinical and Experimental Pediatrics
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• v.57 no.11
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• pp.472-478
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• 2014

Kawasaki disease (KD), an acute vasculitis that primarily affects young children, is the most common acquired paediatric cardiovascular disease in developed countries. While sequelae of arterial inflammation in the acute phase of KD are well documented, its late effects on vascular health are increasingly unveiled. Late vascular dysfunction is characterized by structural alterations and functional impairment in term of arterial stiffening and endothelial dysfunction and shown to involve both coronary and systemic arteries. Further evidence suggests that continuous low grade inflammation and ongoing active remodeling of coronary arterial lesions occur late after acute illness and may play a role in structural and functional alterations of the arteries. Potential importance of genetic modulation on vascular health late after KD is implicated by associations between mannose binding lectin and inflammatory gene polymorphisms with severity of peripheral arterial stiffening and carotid intima-media thickening. The changes in cholesterol and lipoproteins levels late after KD further appear similar to those proposed to be atherogenic. While data on adverse vascular health are less controversial in patients with persistent or regressed coronary arterial aneurysms, data appear conflicting in individuals with no coronary arterial involvements or only transient coronary ectasia. Notwithstanding, concerns have been raised with regard to predisposition of KD in childhood to accelerated atherosclerosis in adulthood. Until further evidence-based data are available, however, it remains important to assess and monitor cardiovascular risk factors and to promote cardiovascular health in children with a history of KD in the long term.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.164-169
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• 2008

Methylmercury (MeHg) is known to have devastating effects on the mammalian nervous system. In order to characterize the mechanism of MeHg-induced neurotoxicity, we investigated the analysis of transcriptional profiles on human 8k cDNA microarray by treatment of $1.4{\mu}M$ MeHg at 3, 12, 24 and 48h in human neuroblastoma SH-SY5Y cell line. Some of the identified genes by MeHg treatment were significant at early time points (3h), while that of others was at late time points (48h). The early response genes that may represent those involved directly in the MeHg response included pantothenate kinase 3, a kinase (PRKA) anchor protein (yotiao) 9, neurotrophic tyrosine kinase, receptor, type 2 gene, associated with NMDA receptor activity regulation or perturbations of central nervous system homeostasis. Also, when SH-SY5Y cells were subjected to a longer exposure (48h), a relative increase was noted in a gene, glutamine-fructose-6-phosphate transaminase 1, reported that overexpression of this gene may lead to the increased resistance to MeHg. To confirm the alteration of these genes in cultured neurons, we then applied real time-RT PCR with SYBR green. Thus, this result suggests that a neurotoxic effect of the MeHg might be ascribed that MeHg alters neuronal receptor regulation or homeostasis of neuronal cells in the early phase. However, in the late phase, it protects cells from neurotoxic effects of MeHg.

• Anxiety and mood
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• v.7 no.1
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• pp.34-39
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• 2011

Objectives : An early age at onset of obsessive compulsive symptoms in family studies has been strongly associated with a more familial form of obsessive compulsive disorder (OCD). Further, many reports have suggested that early- and late- onset OCD represent separate subtypes of the disorder. The aim of this study was to investigate the associations between the glutamate receptor, the ionotropic, n-methyl-d-aspartate (NMDA) subunit 2B gene (GRIN2B) polymorphisms, and onset of OCD in the Korean population. Methods : We recruited 109 OCD patients and classified them into early- (age of onset <18 years) and late-onset groups (age of onset${\geq}$18). Genomic DNA was extracted from their blood after which the genotypes and allelic frequencies of the two GRIN2B polymorphisms (5072T/G and 5988T/C) were compared in the two groups. We also compared genetic data between child- (age of onset${\leq}$15) and adult-onset groups (age of onset${\geq}$19) using the same protocol. Results : There were no significant differences between the early- and late-onset groups with respect to genotype. Moreover, we could not find any differences in genotype frequencies between child and adult-onset groups. Conclusions : Our study suggested that GRIN2B polymorphisms (5072T/G and 5988T/C) do not affect the onset of OCD in Koreans. However, this finding has resulted from a preliminary study and thus, further study is required.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.22-22
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• 2003

This study was conducted to determine effects of polyvinyl alcohol (PVA), fetal bovine serum (FBS) and bovine serum albumin (BSA) on blastocoel formation, cell number, apoptosis and apoptosis-related gene expression of porcine diploid parthenotes developing in vitro. Embryos were collected from 2-cell or late 4-cell diploid parthenotes that activated with electro pulse, and in vitro cultured in the NCSU 23 medium supplemented without or with 0.1% PVA, 10% FBS or 0.4% BSA for day 7. The morphological analysis of apoptosis in embryos was carried out using propidium iodide staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling. The expressions of Bcl-xL, Bak and P53 in blastocyst stage parthenotes and in vivo-derived blastocysts were determined using semiquantitative RT-PCR. The addition of 0.4% BSA to the culture medium enhanced the development of 2- or late 4-cell stage parthenotes to the blastocysts stage (P < 0.01) while FBS decreased the incidence of blastocoel formation. FBS also reduced cell numbers of blastocysts developed from both 2- (P < 0.001) and late 4-cell (P < 0.05) embryos and increased percentage of apoptosis in the blastocysts (P < 0.001). The relative abundance of Bcl-xL mRNA in diploid parthenotes cultured from 2-cell stage in the presence of BSA is similar with that in in vivo derived embryos, but is significantly higher than in parthenotes cultured with FBS, PVA or none protein supplement control. Bak mRNA showed a significant increase at the blastocyst stage in FBS supplement medium. This result suggests that apoptosis related gene expression is significantly affected by protein supplements, which may result in alteration of apoptosis and embryo viability of porcine embryos developing in vitro.