• 한국초지조사료학회지
• /
• 제38권3호
• /
• pp.190-195
• /
• 2018

Cold, salt and heat are the most critical factors that restrict full genetic potential, growth and development of crops globally. However, clarification of genes expression and regulation is a fundamental approach to understanding the adaptive response of plants under unfavorable environments. In this study, we applied an annealing control primer (ACP) based on the GeneFishing approach to identify differentially expressed genes (DEGs) in Italian ryegrass (cv. Kowinearly) leaves under cold, salt and heat stresses. Two-week-old seedlings were exposed to cold ($4^{\circ}C$), salt (NaCl 200 mM) and heat ($42^{\circ}C$) treatments for six hours. A total 8 differentially expressed genes were isolated from ryegrass leaves. These genes were sequenced then identified and validated using the National Center for Biotechnology Information (NCBI) database. We identified several promising genes encoding light harvesting chlorophyll a/b binding protein, alpha-glactosidase b, chromosome 3B, elongation factor 1-alpha, FLbaf106f03, Lolium multiflorum plastid, complete genome, translation initiation factor SUI1, and glyceraldehyde-3-phosphate dehydrogenase. These genes were potentially involved in photosynthesis, plant development, protein synthesis and abiotic stress tolerance in plants. However, this study provides new insight regarding molecular information about several genes in response to multiple abiotic stresses. Additionally, these genes may be useful for enhancement of abiotic stress tolerance in fodder crops as well a crop improvement under unfavorable environmental conditions.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2002년도 추계학술대회
• /
• pp.41-47
• /
• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, $50-80\%$ of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, Improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2002년도 춘계학술대회
• /
• pp.41-47
• /
• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

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

• 한국육종학회지
• /
• 제42권4호
• /
• pp.329-338
• /
• 2010

Drought, salinity and flooding are three important abiotic factors limiting soybean production worldwide. Irrigation, soil reclamation, and drainage systems are not generally available or economically feasible for soybean production. Therefore, productive soybean varieties with tolerance are a cost effective means for reducing yield losses due to these factors. Genetic variability for higher tolerance to drought, salt and flooding is important. However, only a small portion of nearly 200,000 world soybean accessions have been screened to find genotypes with tolerance for use in breeding programs. Evaluation for tolerance to drought, salinity and flooding is difficult due to lack of faster, cost effective, repeatable screening methods. Soybean strains with higher tolerance to the above stresses have been identified. Crosses with lines with drought, salt and flooding tolerance through conventional breeding has made a significant contribution to improving tolerance to abiotic stress in soybean. Molecular markers associated with tolerance to drought, salt and flooding will allow faster, reliable screening for these traits. Germplasm resources, genome sequence information and various genomic tools are available for soybean. Integration of genomic tools coupled with well-designed breeding strategies and effective uses of these resources will help to develop soybean varieties with higher tolerance to drought, salt and flooding.

• The Plant Pathology Journal
• /
• 제28권2호
• /
• pp.202-206
• /
• 2012

Root colonization by the rhizobacterium Pseudomonas chlororaphis O6 in Arabidopsis thaliana Col-0 plants resulted in induced tolerance to drought and salinity caused by halide salt-generated ionic stress but not by osmotic stress caused by sorbitol. Stomatal apertures decreased following root colonization by P. chlororaphis O6 in both wild-type and ABA-insensitive Arabidopsis mutant plants. These results suggest that an ABA-independent stomatal closure mechanism in the guard cells of P. chlororaphis O6-colonized plants could be a key phenotype for induced systemic tolerance to drought and salt stress.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2005년도 한국식물병리학회 임시총회 및 춘계학술발표회
• /
• pp.16-19
• /
• 2005

• BMB Reports
• /
• 제42권5호
• /
• pp.271-276
• /
• 2009

Sweetpotato (Ipomoea batatas (L). Lam.) is relatively tolerant to unfavorable growth conditions such as drought, yet has not been exploited to provide a better understanding of the molecular basis of drought stress tolerance. We obtained 983 high-quality expressed sequence tags of 100 bp or longer (average length of 700 bp) from cDNA libraries of detached white fibrous root tissues by subjecting them to dehydration for 6 h. The 431 cDNAs were each assigned a function by alignment using the BLASTX algorithm. Among them, three genes associated with various abiotic stresses and nine genes not previously associated with drought stress were selected for expression pattern analysis through detailed reverse transcription-polymerase chain reaction. The direct and indirect relationships of the 12 genes with drought tolerance mechanisms were ascertained at different developmental stages and under various stress conditions.

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

• Journal of Microbiology and Biotechnology
• /
• 제28권7호
• /
• pp.1217-1224
• /
• 2018

Seaweeds produce antioxidants to counteract environmental stresses, and these antioxidant genes are regarded as important defense strategies for marine algae. In this study, the expression of Pyropia yezoensis (Bangiales, Rhodophyta) ascorbate peroxidase (PyAPX) and manganese-superoxide dismutase (PyMnSOD) was examined by qRT-PCR in P. yezoensis blades under abiotic stress conditions. Furthermore, the functional relevance of these genes was explored by overexpressing them in Chlamydomonas. A comparison of the different expression levels of PyAPX and PyMnSOD after exposure to each stress revealed that both genes were induced by high salt and UVB exposure, being increased approximately 3-fold after 12 h. The expression of the PyAPX and PyMnSOD genes also increased following exposure to $H_2O_2$. When these two genes were overexpressed in Chlamydomonas, the cells had a higher growth rate than control cells under conditions of hydrogen peroxide-induced oxidative stress, increased salinity, and UV exposure. These data suggest that Chlamydomonas is a suitable model for studying the function of stress genes, and that PyAPX and PyMnSOD genes are involved in the adaptation and defense against stresses that alter metabolism.