• 한국작물학회지
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• 제60권3호
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• pp.293-299
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• 2015

밀의 등숙기간, 종자 수, 종자무게와 관련된 SSR 마커 14개를 이용하여 터키에서 분양받은 내고온성 유전자원 23개와 국산밀 품종 7개, Chinese spring 1개 등 31개를 분석한 결과, 전체 86개의 대립유전자(평균 6.14개)가 확인되었다. 평균 PIC 값은 0.64로 나타났다. 다형성 분석을 통한 마커 데이터를 이용하여 계통 분석을 한 결과 크게 세 그룹으로 형성되었다. 올밀이 가장 바깥 그룹으로 형성되었고 올그루, 고소, 조품 등이 터키자원과 다르게 단일 그룹으로 형성되었다. 금강, 조경, 백중 등 세 품종은 터키 자원들과 같은 그룹으로 나타났지만 밀접하게 연관되어 있지는 않은 것으로 나타났다. 국내 품종 중 올, 올그루, 조품, 고소 등 4개와 금강, 조경, 백중 등 3개가 서로 다른 그룹으로 형성되었다. 두 그룹의 차이는 파성 II와 III의 차이로 구별되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권6호
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• pp.818-823
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• 2012

Tall fescue (Festuca arundinacea Schreb.) is an important cool season forage plant that is not well suited to extreme heat, salts, or heavy metals. To develop transgenic tall fescue plants with enhanced tolerance to abiotic stress, we introduced an alfalfa Hsp23 gene expression vector construct through Agrobacterium-mediated transformation. Integration and expression of the transgene were confirmed by polymerase chain reaction, northern blot, and western blot analyses. Under normal growth conditions, there was no significant difference in the growth of the transgenic plants and the non-transgenic controls. However, when exposed to various stresses such as salt or arsenic, transgenic plants showed a significantly lower accumulation of hydrogen peroxide and thiobarbituric acid reactive substances than control plants. The reduced accumulation of thiobarbituric acid reactive substances indicates that the transgenic plants possessed a more efficient reactive oxygen species-scavenging system. We speculate that the high levels of MsHsp23 proteins in the transgenic plants protect leaves from oxidative damage through chaperon and antioxidant activities. These results suggest that MsHsp23 confers abiotic stress tolerance in transgenic tall fescue and may be useful in developing stress tolerance in other crops.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.425-429
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• 2002

Saccharomyces cerevisiae KNU5377 was examined to assay the recovering capacity against heat and other stressors. Along with a particular fermentation ability that is able to produce ethanol even at high temperature such as $40^{\circ}C$ with a comparable rate to the fermentation at $33^{\circ}C$, this strain also exhibited higher viability than a reference strain owing to its own thermotolerance that conferred the survival after the severe heat shock at $60^{\circ}C$ for 30 minutes. Furthermore, this strain showed outstanding tolerances against $H_2O_2$, ethanol and some chemical compounds. But, especially due to the thermotolerance, this strain has been suspected of other species of yeast. However, ITS (internally transcribed spacer) 1 and 2 sequencing data confirmed this strain was a typical strain of S. cerevisiae. The outstanding tolerances to various environmental stressors Indicate this S. cerevisiae KNU5377 is enough to use both as an on-site potential strain for world-wide alcohol fermentation industry and as a model strain for researches into the routes to acquire the tolerance to various stressors.

• 소성∙가공
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• 제31권2호
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• pp.51-56
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• 2022

In this study, finite element analyses were performed by applying a stress ring and split die design to relieve the tensile stress acting on the die due to high surface pressure during warm-closed forging. The applied material was a yield-ratio-control-steel (YRCS). It was used without quenching or tempering after forging. In the case of stress rings design, the number of stress rings and the tolerance for shrink fit were different. Vertical and horizontal splits were applied for insert die split design. Case 5 die with three stress rings, 0.2 % shrink fit tolerance, and vertical split was selected as an effective die design for tensile stress reduction. Based on die stress reduction analyses, Case 5 die for warm-closed forging was produced and smooth forgeability was secured, making it possible to manufacture forging product of yoke with the required geometry. In addition, controlled cooling using warm forging heat was applied to secure mechanical properties of yokes. When oil cooling was used for direct controlled cooling after warm-closed forging, a relatively uniform Rockwell hardness distribution and high mechanical properties could be obtained.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1663-1670
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• 2014

The objective of this study was to determine the perceptions and knowledge of farmers of heat stress and tick resistance in cattle. A cross-sectional survey was conducted and 110 farmers in four villages in the sour and sweet velds of the Eastern Cape Province, South Africa were interviewed. The associations among area (municipality), gender, age, level of education, employment and religion were computed using Chi-square tests. The majority of the respondents had on average 4 bulls, 4 cows, 4 heifers, 4 calves, and 4 oxen. Milk was considered as the major (28.3%) reason for keeping cattle. Most farmers owned non-descript (72.6%), and Nguni (45.3%) cattle because of their heat tolerance (54.7%), tick resistance (54.7%), and milking ability (28.2%) traits. Excessive panting (56.6%) and disease transmission (76%) were regarded as the major effects of heat stress and tick infestation in cattle, respectively. About 50% of the respondents agreed that hair length influences tick resistance and 47.17% considered coat colour when acquiring cattle. In the sampled areas, ticks were prevalent in the summer season (93%), and 77.36% of the respondents use acaricides every fortnight. Gall sickness was reported to be a major problem in the cattle herds by 36.79% of the respondents. Our results showed that farmers in the two municipalities had knowledge of cattle adaptation to heat stress and tick resistance.

• Molecules and Cells
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• 제40권8호
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• pp.577-586
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• 2017

Phytocystatins (PhyCYSs) are plant-specific proteinaceous inhibitors that are implicated in protein turnover and stress responses. Here, we characterized a PhyCYS from Arabidopsis thaliana, which was designated AtCYS5. RT-qPCR analysis showed that the expression of AtCYS5 in germinating seeds was induced by heat stress (HS) and exogenous abscisic acid (ABA) treatment. Analysis of the expression of the ${\beta}-glucuronidase$ reporter gene under the control of the AtCYS5 promoter showed that AtCYS5 expression during seed germination was induced by HS and ABA. Constitutive overexpression of AtCYS5 driven by the cauliflower mosaic virus 35S promoter led to enhanced HS tolerance in transgenic Arabidopsis, which was characterized by higher fresh weight and root length compared to wild-type (WT) and knockout (cys5) plants grown under HS conditions. The HS tolerance of AtCYS5-overexpressing transgenic plants was associated with increased insensitivity to exogenous ABA during both seed germination and post-germination compared to WT and cys5. Although no HS elements were identified in the 5'-flanking region of AtCYS5, canonical ABA-responsive elements (ABREs) were detected. AtCYS5 was upregulated in ABAtreated protoplasts transiently co-expressing this gene and genes encoding bZIP ABRE-binding factors (ABFs and AREB3). In the absence of ABA, ABF1 and ABF3 directly bound to the ABREs in the AtCYS5 promoter, which activated the transcription of this gene in the presence of ABA. These results suggest that an ABA-dependent pathway plays a positive role in the HS-responsive expression of AtCYS5 during seed germination and post-germination growth.

• Journal of Plant Biotechnology
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• 제43권3호
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• pp.302-310
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• 2016

A study aimed at identifying putative drought responsive genes that confer tolerance to water stress deficit in tea plants was conducted in a 'rain-out shelter' using potted plants. Eighteen months old drought tolerant and susceptible tea cultivars were each separately exposed to water stress or control conditions of 18 or 34% soil moisture content, respectively, for three months. After the treatment period, leaves were harvested from each treatment for isolation of RNA and cDNA synthesis. The cDNA libraries were sequenced on Roche 454 high-throughput pyrosequencing platform to produce 232,853 reads. After quality control, the reads were assembled into 460 long transcripts (contigs). The annotated contigs showed similarity with proteins in the Arabidopsis thaliana proteome. Heat shock proteins (HSP70), superoxide dismutase (SOD), catalase (cat), peroxidase (PoX), calmodulinelike protein (Cam7) and galactinol synthase (Gols4) droughtrelated genes were shown to be regulated differently in tea plants exposed to water stress. HSP70 and SOD were highly expressed in the drought tolerant cultivar relative to the susceptible cultivar under drought conditions. The genes and pathways identified suggest efficient regulation leading to active adaptation as a basal defense response against water stress deficit by tea. The knowledge generated can be further utilized to better understand molecular mechanisms underlying stress tolerance in tea.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1557-1567
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• 2012

Glutathione reductase (GR, E.C. 1.6.4.2) is an important enzyme that reduces glutathione disulfide (GSSG) to a sulfydryl form (GSH) in the presence of an NADPH-dependent system. This is a critical antioxidant mechanism. Owing to the significance of GR, this enzyme has been examined in a number of animals, plants, and microbes. We performed a study to evaluate the molecular properties of GR (OsGR) from rice (Oryza sativa). To determine whether heterologous expression of OsGR can reduce the deleterious effects of unfavorable abiotic conditions, we constructed a transgenic Saccharomyces cerevisiae strain expressing the GR gene cloned into the yeast expression vector p426GPD. OsGR expression was confirmed by a semiquantitative reverse transcriptase polymerase chain reaction (semiquantitative RT-PCR) assay, Western-blotting, and a test for enzyme activity. OsGR expression increased the ability of the yeast cells to adapt and recover from $H_2O_2$-induced oxidative stress and various stimuli including heat shock and exposure to menadione, heavy metals (iron, zinc, copper, and cadmium), sodium dodecyl sulfate (SDS), ethanol, and sulfuric acid. However, augmented OsGR expression did not affect the yeast fermentation capacity owing to reduction of OsGR by multiple factors produced during the fermentation process. These results suggest that ectopic OsGR expression conferred acquired tolerance by improving cellular homeostasis and resistance against different stresses in the genetically modified yeast strain, but did not affect fermentation ability.

• 생약학회지
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• 제46권1호
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• pp.38-43
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• 2015

Ligularia stenocephala has a wide range of types of constituents with various pharmacological properties. Here in this study, we examined the effect of methanolic extract of L. stenocephala (MLS) on the lifespan and stress tolerance using Caenorhabditis elegans model system. We found that lifespan of wild-type worms was significantly lengthened in the presence of MLS in a dose dependent manner. MLS also elevated the tolerance of worms against osmotic, heat shock, and oxidative stress. We also demonstrated in vivo antioxidant capacity of MLS by checking intracellular reactive oxygen species levels as well as antioxidant enzyme activities such as catalase and superoxide dismutase. We further investigated several aging-related factors, including pharyngeal pumping rate and body length. Here, we showed that MLS exerts longevity effect independent of both factors. In addition, body movement of aged worms was significantly elevated, suggesting MLS could enhance healthspan as well as lifespan.

• Journal of Applied Biological Chemistry
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• 제54권4호
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• pp.244-251
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• 2011

Galactinol and rafinose accumulation in plants is associated with stressful environmental conditions such as cold, heat, or dehydration by the action of galactinols synthase (GolS) in the raffinose family of oligosaccharides biosynthetic pathway from UDP-galactose. Moreover, several reports mentioned that GolS transcription is up regulated by various environmental stresses like cold, heat, dehydration. Therefore, to determine whether MoGolS1 was induced with the abiotic stress we analyzed the expression pattern of the gene under various abiotic stresses like heat, cold, abscisic acid, sucrose and salt concentration in the lemon balm plants grown in standard MS medium. The MoGolS1 gene was 981-bp in length encoding 326 amino acids in its sequence and shared 77 and 76% sequence similarity with Arabidopsis thaliana galactinol synthase4 (AtGolS4) and AtGolS1 genes respectively. The MoGolS1 gene was strongly expressed by the abiotic stress induced by sucrose, ABA or heat shock. It was also expressed in responses to cold, Identification and Functional Characterization of the GALACTINOL SYNTHASgene induction with various stresses may be possible for itscrucial function in abiotic stress tolerance in plants, providing a good engineering target for genetic engineering.