• The Plant Pathology Journal
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• v.35 no.5
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• pp.393-405
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• 2019

Survival factor 1 (Svf1) is a protein involved in cell survival pathways. In Saccharomyces cerevisiae, Svf1 is required for the diauxic growth shift and survival under stress conditions. In this study, we characterized the role of FgSvf1, the Svf1 homolog in the homothallic ascomycete fungus Fusarium graminearum. In the FgSvf1 deletion mutant, conidial germination was delayed, vegetative growth was reduced, and pathogenicity was completely abolished. Although the FgSvf1 deletion mutant produced perithecia, the normal maturation of ascospore was dismissed in deletion mutant. The FgSvf1 deletion mutant also showed reduced resistance to osmotic, fungicide, and cold stress and reduced sensitivity to oxidative stress when compared to the wild-type strain. In addition, we showed that FgSvf1 affects glycolysis, which results in the abnormal vegetative growth in the FgSvf1 deletion mutant. Further, intracellular reactive oxygen species (ROS) accumulated in the FgSvf1 deletion mutant, and this accumulated ROS might be related to the reduced sensitivity to oxidative stress and the reduced resistance to cold stress and fungicide stress. Overall, understanding the role of FgSvf1 in F. graminearum provides a new target to control F. graminearum infections in fields.

• Molecules and Cells
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• v.45 no.11
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• pp.806-819
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• 2022

Synaptic accumulation of α-synuclein (α-Syn) oligomers and their interactions with VAMP2 have been reported to be the basis of synaptic dysfunction in Parkinson's disease (PD). α-Syn mutants associated with familial PD have also been known to be capable of interacting with VAMP2, but the exact mechanisms resulting from those interactions to eventual synaptic dysfunction are still unclear. Here, we investigate the effect of α-Syn mutant oligomers comprising A30P, E46K, and A53T on VAMP2-embedded vesicles. Specifically, A30P and A53T oligomers cluster vesicles in the presence of VAMP2, which is a shared mechanism with wild type α-Syn oligomers induced by dopamine. On the other hand, E46K oligomers reduce the membrane mobility of the planar bilayers, as revealed by single-particle tracking, and permeabilize the membranes in the presence of VAMP2. In the absence of VAMP2 interactions, E46K oligomers enlarge vesicles by fusing with one another. Our results clearly demonstrate that α-Syn mutant oligomers have aberrant effects on VAMP2-embedded vesicles and the disruption types are distinct depending on the mutant types. This work may provide one of the possible clues to explain the α-Syn mutant-type dependent pathological heterogeneity of familial PD.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.276-276
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• 2022

Wheat is one of the most widely grown food crops worldwide. Extreme precipitation and wind disturbances increased due to the abnormal climate, which resulted in increased lodging. Introduction of dwarf genes in wheat significantly increased lodging resistance and productivity in wheat breeding. In this study, we performed the genotyping of dwarfing genes between 'Keumkang' and 'Komac 5' ('Keumkang' mutant). In addition, we investigated the relationship between plant height and several phenotypic characters using F₂ segregation populations derived from crosses between the two varieties. There was no significant difference in phenotypic characters between the two varieties except for plant height. In the genotyping analysis using dwarfing genes, mutations of two dwarfing gene were found to be induced between the two varieties. The four genotypes of the F₂ populations from a crossing between 'Keumkang' and 'Komac 5' were used to compare and evaluate the effects of two dwarfing genes. Plants with two single mutant dwarfing gene and double mutant dwarfing gene revealed reduced plant heights than control plants by 4.5%, 6.9%, and 33.2%, respectively. The phenotype analysis showed that double mutant dwarfing gene affected wheat stem growth as the length decreases from the second node, resulting in decreased plant height. However, there were no significant differences in the agronomic traits between mutant plants and control plant. These results may provide novel information about the effect of double mutant dwarfing gene on plant height, and may help improve lodging tolerance and wheat yield.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.3
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• pp.203-212
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• 2020

Promyelocytic leukemia (PML) gene, through alternative splicing of its C-terminal region, generates several PML isoforms that interact with specific partners and perform distinct functions. The PML protein is a tumor suppressor that plays an important role by interacting with various proteins. Herein, we investigated the effect of the PML isoforms on oncostatin M (OSM)-induced signal transducer and activator of transcription-3 (STAT-3) transcriptional activity. PML influenced OSM-induced STAT-3 activity in a cell type-specific manner, which was dependent on the p53 status of the cells but regardless of PML isoform. Interestingly, overexpression of PML exerted opposite effects on OSM-induced STAT-3 activity in p53 wild-type and mutant cells. Specifically, overexpression of PML in the cell lines bearing wild-type p53 (NIH3T3 and U87-MG cells) decreased OSM-induced STAT-3 transcriptional activity, whereas overexpression of PML increased OSM-induced STAT-3 transcriptional activity in mutant p53-bearing cell lines (HEK293T and U251-MG cells). When wild-type p53 cells were co-transfected with PML-IV and R273H-p53 mutant, OSM-mediated STAT-3 transcriptional activity was significantly enhanced, compared to that of cells which were transfected with PML-IV alone; however, when cells bearing mutant p53 were co-transfected with PML-IV and wild-type p53, OSM-induced STAT-3 transcriptional activity was significantly decreased, compared to that of transfected cells with PML-IV alone. In conclusion, PML acts together with wild-type or mutant p53 and influences OSM-mediated STAT-3 activity in a negative or positive manner, resulting in the aberrant activation of STAT-3 in cancer cells bearing mutant p53 probably might occur through the interaction of mutant p53 with PML.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.206-216
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• 2015

To clarify the role of surface protective antigen A (SpaA) in the pathogenesis of Erysipelothrix rhusiopathiae C43065 (serotype 2), the spaA deletion mutant of E. rhusiopathiae ${\Delta}spaA$ was constructed by homologous recombination. The virulence of the ${\Delta}spaA$ mutant decreased more than 76-fold compared with that of the wild-type strain C43065 in mice. The mutant strain was sensitive to the bactericidal action of swine serum, whereas the wild-type strain was resistant. The adhesion of wild-type strain to MEF cells was inhibited significantly by treatment with rabbit antiserum against recombinant SpaA (rSpaA) as compared with the treatment with normal rabbit serum, but the mutant strain was not affected. The mutant strain was readily taken up by mouse peritoneal macrophages in the normal rabbit serum, whereas the wild-type strain was resistant. Whereas the rabbit antiserum against rSpaA promoted the phagocytosis of wild-type strain by macrophages, the mutant strain was not affected. In addition, mice vaccinated with the formalin-killed mutant strain were provided 40% protection against challenge by the homologous virulent strain as compared with those with wild-type strain, NaOH-extracted antigen, or rSpaA, which provided more than 80% protection against the same infection. These suggested that SpaA has an important role in the pathogenesis of E. rhusiopathiae infection and could be a target for vaccination against swine erysipelas.

• Journal of Nutrition and Health
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• v.33 no.1
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• pp.5-12
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• 2000

The control of food intake is a complex phenomenon caused by interactions between central and peripheral control mechanisms. The hypothalamic and brain stem regions have been identified as centers for food intake and energy expenditure in animals and humans. Of these, the ventromedial and lateral hypothalamic areas are involved in the control of food intake. Also, large amounts of neurotransmitters known to be involved in feeding are present in the hippocampus. Paricularly, tryptophan hydroxylase(TPH), known as a factor in the control of food intake, is present in high levels in the paraventricular nucleus of the hypothalamus and the hippocampus. In this study, TPH expression levels in the hypothalamic and hippocampal regions of fasting, anorexia mutant, and control mice were compared using RT-PCR and immunohistochemical methods. Differences in body weight among the fasting, anorexia mutant, and control groups wire observed. No statistical significance was noted in the number of TPH-immunoactivity in the hypothalamic nuclei, but relatively higher populations of such fibers were observed in the fasting group : the control group yielded samples with an overall value of 170.3${\pm}$3.5 in terms of immunoreactivity-induced optical density, whereas the fasting group yielded a value of 168.3${\pm}$2.6, and the anorexia mutant group 171.3${\pm}$0.8(lower values represent higher immunoreactivity), In fasting mice, stained neuronal bodies were observed in the CA3 and dentate gyrus regions of the hippocampus, which was different from the hippocampal regions of the control and anorexia mutant mice. The RT-PCR procedures were performed using whole brains, precluding any statistically noticeable findings in relation to specific regions, although the fasting and anorexia mutant groups showed 123.3% and 102.9%, respectively, of the TPH mRNA level in the control. The overall results present evidences of the role of TPH in the decrease in food intake during fasting caused by exogenic factors and in genetically acquired anorexia. (Korean J Nutrition 33(1) : 5-12, 2000)

• Journal of Sericultural and Entomological Science
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• v.30 no.2
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• pp.88-95
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• 1988

The structure ki mutant chorion is described by the ultrastructural level with the scanning electron microscope. The micropyle on the anterior, posterior, leteral and dorsal side region surface patterns do not so much differ from ki mutant and normal strains. The surface structure of ventral side of ki mutant, which is the presumptive embryonic region in oocytes, were netted part corresponding to the boundary of follicle cells that is similar to lateral side structure of egg-shell. The eggshell thickness of ventral side on the ki mutant is mostly thicker. However, the structure of transverse section of normal and ki mutant egg-shell are composed of the outer, middle and inner layers. The ki not effects the formation of the lamellar layer in the egg-shell. It is observed that the characteristic structure in ki mutant egg chorion may be attributed to a areal specificity of epithelium in ventral side of egg-shell formation, and it affects the process of the accumulation of secreted chorionic material and the egg-shell architecture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1388-1393
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• 2014

To enzymatically prepare amylopectin cluster (APC), cyclodextrin glucanotransferase (CGTase I-5) and its mutant enzyme from alkalophilic Bacillus sp. I-5 were employed, after which the hydrolysis patterns of CGTase wild-type and its mutant enzyme toward amylopectin were investigated using multi-angle laser light scattering. CGTase wild-type dramatically reduced the molecular weight of waxy rice starch at the initial reaction, whereas the mutant enzyme degraded waxy rice starch relatively slowly. Based on the results, the molecular weight of one cluster of amylopectin could be about $10^4{\sim}10^5g/mol$. To determine production of cyclic glucans from amylopectin, matrix-assisted laser desorption ionization time-of-flight mass spectrometry was performed. CGTase I-5 produced various types of cyclic maltooligosaccharides from amylopectin, whereas the mutant enzyme hardly produced any.

• KSBB Journal
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• v.9 no.1
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• pp.16-25
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• 1994

Sporulation mutants of Bacillus subtilis were developed for overproduction of heterologous proteins. The strains spoOJ spoIIG, and spoOJ spoIIG double mutant were constructed from two pretense-delfted mutant (DB104). The vector containing aprE gene was integrated in the chromosome of each strain, then the morphology of each strain was observed by TEM (trasmission electron microscopy). The morphology of spoOJ mutant and spoIIG mutant coincides with the description of the previous reports, respectively. The sporulating cells of spoOJ SpoIIG double mutation resemble spoIIG mutant more similarly, but with a little rougher cell wall membrane. The spoOJ mutation in B. subtilis gives negative effect on aprE activity with only a decreased sporulation frequency. On the contrary spoIIG mutation increases the aprE activity twice with an undetectable sporulation frequency. In the case of spoOJ and spolIG, i. e. double mutation, the effect of spoOJ on aprE activity seems to be relieved and the double mutant shows more or less the same aprE activity compared to spoIIG mutant.

• BMB Reports
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• v.32 no.1
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• pp.6-11
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• 1999

To understand the function of phospholipids and their fatty acid composition on the morphological changes in the amp 1-4 mutant of Arabidopsis, the mutant was compared to the wild-type Arabidopsis by TLC, HPTLC, phosphorous assay, HPLC, and GC. In the mutant, phosphatidylethanolamine (PE) was increased 5-fold and phosphatidylglycerol (PG) was decreased 1.2-fold (nmol phosphorous/g tissue). Inositol phospholipids showed a generally increased trend ranging from 1.4-to 3.0-fold (nmol inositol/g tissue). When fatty acid composition of the mutant was compared to the wild-type, linoleic (18:2) and linolenic (18:3) acids of phosphatidylcholine (PC) and PG were decreased but palmitoleic acid (16:1) and oleic acid (18:1) of PC was increased 2.5- and 2.1-fold (mol%), respectively. In galactolipids, myristic acid (14:0) of monogalactosyl-diacylglycerol (MGDG) were increased 5.8-fold (mol%). Among the inositol phospholipids, lysophosphatidylinositol (L-PI) and phosphatidylinositol 4,5-bisphosphate ($PIP_2$) showed 4-and 1.9-fold (mol%) increase of 16:1, respectively. These results suggest that the increase of PE, the decrease of PG, the increase of inositol phospholipids, and the altered fatty acid composition are related to the phenotypic changes affecting the morphological features, and might cause different physiological changes in the amp 1-4 mutant compared to wild-type Arabidopsis.