• Journal of Ginseng Research
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• 제32권4호
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• pp.300-304
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• 2008

14년생 인삼의 뿌리로부터 cDNA library를 제작한 후 무작위로 뽑은 EST clone 중에서 cysteine proteinase(CP) 유전자에 높은 상동성을 나타내는 clone 6개를 선발하였고 이를 바탕으로 PgCysP1을 제작하였다. 인삼의 CP 유전자는 전장의 길이가 1,398bp로 366개의 아미노산을 코딩하는 1,101bp의 ORF를 가지고 있다. PgCysP1의 아미노산 서열과 이차구조를 분석한 결과, 기존에 보고된 식물들과 높은 상동성을 나타내었으며 PgCysP1는 papain family에 속하는 것으로 확인되었다. RT-PCR 분석결과, 인삼의 PgCysP1는 NaCl, 저온, wound, salicylic acid에 대해 그 발현 양상이 상동성을 나타내는 다른식물의 CP 유전자 발현과 유사한 양성을 보였고, 이에 PgCysP1은 CP gene으로 사료되며, 앞으로 인삼 식물체의 환경 스트레스에 대한 내성 연구가 요구된다.

• 한국자원식물학회지
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• 제23권2호
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• pp.172-178
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• 2010

천연집단에 서식하는 개비자나무 개체들을 이용해 무생물 및 생물적 환경인자가homoharringtonine(HHT) 함량에 미치는 영향을 조사하여 향후 항암제 가능성이 있는 HHT의 고부가가치 산업적인 생산이 기대되는 연구에 기초자료를 제공하고자 본 연구를 수행하였다. 무생물적 환경인자(토양습도, 토양pH, 서식밀도, 기온)와 HHT 함량과의 상관관계에 있어 HHT 는 토양습도(0.77)와 토양pH(-0.68)에서 높은 상관을 보였다. 고도에 따른 무생물적 환경인자 (토양습도, 토양pH)와 HHT 의 함량 관계에 관해 다중회귀 분석을 실시한 결과, 토양 습도의 회귀계수($26.48^{***}$) 만 유의하여 토양 습도가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 생물적 환경인자(damage index)에 따른 HHT 함량에 미치는 영향을 살펴 본 결과, HHT는 2차곡선회귀적으로 증가하다 감소하는($H=278.23+1242D-398.87D^2$) 경향을 보였고 damage index는 HHT 함량에 높은 영향을 미치는 것으로 분석되었다. 마지막으로 HHT 의 함량에 영향을 미치는 최적환경인자를 분석한 결과, damage index와 토양 습도 모두가 2차다항회귀식으로 가장 적합하였고 결정계수는 각각 0.73와 0.67로 damage index가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 이는 섭식자 또는 균류와 같은 스트레스로 인한 방어기작이 HHT 의 생성에 높은 영향을 미치는 것으로 판단된다.

• Journal of Plant Biotechnology
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• 제42권3호
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• pp.168-179
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• 2015

We previously identified the rice gene, OsSAP, as an encoder of a highly conserved putative senescence-associated protein that was shown to have anti-apoptotic activity. To confirm the role of OsSAP in inducing abiotic stress tolerance in rice, we introduced OsSAP and AtBI-1, a plant homologue of Bax inhibitor-1, under the control of the CaMV 35S promoter into the rice genome through Agrobacterium-mediated transformation. The OsSAP transformants showed a similar chlorophyll index after salinity treatments with AtBI-1. Furthermore, we compared the effects of salinity stress on leaves and roots by examining the hormone levels of abscisic acid (ABA), jasmonic acid (JA), gibberellic acid (GA3), and zeatin in transformants compared to the control. With the exception of phytohormones, stress-induced changes in hormone levels putatively related to stress tolerance have not been investigated previously. Hormonal level analysis confirmed the lower rate of stress in the transformants compared to the control. The levels of ABA and JA in OsSAP and AtBI-1 transformants were similar, where stress rates increased after one week and decreased after a two week period of drought; there was a slightly higher accumulation compared to the control. However, a similar trend was not observed for the level of zeatin, as the decrease in the level of zeatin accumulation differed in both OsSAP and AtBI-1 transformants for all genotypes during the early period of salinity stress. The GA3 level was detected under normal conditions, but not under salinity stress.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.235-235
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• 2017

Chromium (Cr) toxicity is hazardous to the seed germination, growth, and development of plants. ${\gamma}$-Aminobutyric acid (GABA) is a non-protein amino acid and is involved in stress tolerance in plants. To investigate the effects of GABA in alleviating Cr toxicity, we treated eight-d-old mustard (Brassica juncea L.) seedlings with Cr (0.15 mM and 0.3 mM $K_2CrO_4$, 5 days) alone and in combination with GABA ($125{\mu}M$) in a semi-hydroponic medium. The roots and shoots of the seedlings accumulated Cr in a dose-dependent manner, which led to an increase in oxidative damage [lipid peroxidation; hydrogen peroxide ($H_2O_2$) content; superoxide ($O{_2}^{{\cdot}-}$) generation; lipoxygenase (LOX) activity], MG content, and disrupted antioxidant defense and glyoxalase systems. Chromium stress also reduced growth, leaf relative water content (RWC), and chlorophyll (chl) content but increased phytochelatin (PC) and proline (Pro) content. Furthermore, supplementing the Cr-treated seedlings with GABA reduced Cr uptake and upregulated the non-enzymatic antioxidants (ascorbate, AsA; glutathione, GSH) and the activities of the enzymatic antioxidants including ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glyoxalase I (Gly I), and glyoxalase II (Gly II), and finally reduced oxidative damage. Adding GABA also increased leaf RWC and chl content, decreased Pro and PC content, and restored plant growth. These findings shed light on the effect of GABA in improving the physiological mechanisms of mustard seedlings in response to Cr stress.

• Journal of Microbiology and Biotechnology
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• 제30권10호
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• pp.1500-1509
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• 2020

Drought is a major abiotic factor and has drastically reduced crop yield globally, thus damaging the agricultural industry. Drought stress decreases crop productivity by negatively affecting crop morphological, physiological, and biochemical factors. The use of drought tolerant bacteria improves agricultural productivity by counteracting the negative effects of drought stress on crops. In this study, we isolated bacteria from the rhizosphere of broccoli field located in Daehaw-myeon, Republic of Korea. Sixty bacterial isolates were screened for their growth-promoting capacity, in vitro abscisic acid (ABA), and sugar production activities. Among these, bacterial isolates YNA59 was selected based on their plant growth-promoting bacteria traits, ABA, and sugar production activities. Isolate YNA59 highly tolerated oxidative stress, including hydrogen peroxide (H₂O₂) and produces superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities in the culture broth. YNA59 treatment on broccoli significantly enhanced plant growth attributes, chlorophyll content, and moisture content under drought stress conditions. Under drought stress, the endogenous levels of ABA, jasmonic acid (JA), and salicylic acid (SA) increased; however, inoculation of YNA59 markedly reduced ABA (877 ± 22 ng/g) and JA (169.36 ± 20.74 ng/g) content, while it enhanced SA levels (176.55 ± 9.58 ng/g). Antioxidant analysis showed that the bacterial isolate YNA59 inoculated into broccoli plants contained significantly higher levels of SOD, CAT, and APX, with a decrease in GPX levels. The bacterial isolate YNA59 was therefore identified as Variovorax sp. YNA59. Our current findings suggest that newly isolated drought tolerant rhizospheric Variovorax sp. YNA59 is a useful stress-evading rhizobacterium that improved drought-stress tolerance of broccoli and could be used as a bio-fertilizer under drought conditions.

• Journal of Plant Biotechnology
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• 제44권1호
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• pp.69-75
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• 2017

Dormancy-associated protein (DRM)은 식물의 휴면생리에 관여하는 대표적인 단백질로 거의 모든 식물에 보존되어 있다. 최근 DRM 유전자가 비생물적 스트레스 반응에 관여하는 것으로 알려지면서 이 유전자의 특성구명 연구가 여러 식물에서 이루어지고 있다. 그러나 아직까지 나무에서는 DRM 유전자에 대한 연구가 거의 없는 실정이다. 따라서 본 연구에서는 DRM 유전자를 현사시나무(Populus alba ${\times}$ P. glandulosa)에서 분리하여 이를 PagDRM1이라 명명하고, 유전자의 구조와 발현특성을 조사하였다. PagDRM1 유전자는 123개의 아미노산으로 구성된 단백질을 암호화하며, 2개의 영역(Domain I과 Domain II)이 잘 보존되어 있다. PagDRM1은 현사시나무의 염색체에 1 ~ 2 copy가 존재하며, 줄기에서 가장 높게 발현하였고 성숙 잎, 뿌리 및 꽃에서도 높은 발현 수준을 나타내었다. 현탁배양세포의 생장주기에서는 늦은 지수생장기부터 정지기까지 높게 발현하였다. 또한 PagDRM1은 건조와 염 스트레스에 반응하여 발현이 증가하는 것으로 나타났다. 식물호르몬 처리에 의해서는 ABA와 GA 처리에 의한 발현 증가를 나타내었다. 따라서 PagDRM1은 식물의 휴면유도 과정에서 중요한 역할을 할 뿐만 아니라 환경 스트레스 내성에도 기여하는 것으로 생각된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.7-7
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• 2017

Unfavorable weather and soil conditions reduce rice yield and land and water productivity, aggravating existing encounters of poverty and food insecurity. These conditions are foreseen to worsen with climate change and with the unceasing irrational human practices that progressively debilitate productivity despite global appeals for more food. Our understanding of plant responses to abiotic stresses is advancing and is complex, involving numerous critical processes - each controlled by several genetic factors. Knowledge of the physiological and molecular mechanisms involved in signaling, response and adaptation, and in some cases the genes involved, is advancing. Moreover, the genetic diversity being unveiled within cultivated rice and its wild relatives is providing ample resources for trait and gene discovery, and this is being scouted for rice improvement using modern genomics and molecular tools. Development of stress tolerant varieties is now being fast-tracked through the use of DNA markers and advanced breeding strategies. Large numbers of drought, submergence and salt tolerant varieties were commercialized over recent years in South and Southeast Asia and more recently in Africa. These varieties are making significant changes in less favorable areas, transforming lives of smallholder farmers - progress considered incredulous in the past. The stress tolerant varieties are providing assurance to farmers to invest in better management of their crops and the ability to adjust their cropping systems for even higher productivity and more income, sparking changes analogous to that of the first green revolution, which previously benefited only favorable irrigated and rainfed areas. New breeding tools using markers for multiple stresses made it possible to develop more resilient, higher yielding varieties to replace the aging and obsolete varieties still dominating these areas. Varieties with multiple stress tolerances are now becoming available, providing even better security for farmers and lessening their production risks even in areas affected by complex and overlapping stresses. The progress made in these less favorable areas triggered numerous favorable changes at the national and regional levels in several countries in Asia, including adjusting breeding and dissemination strategies to accelerate outreach and enabling changes at higher policy levels, creating a positive environment for faster progress. Exploiting the potential of these less productive areas for food production is inevitable, to meet the escalating global needs for more food and sustained production systems, at times when national resources are shrinking while demand for food is mounting. However, the success in these areas requires concerted efforts to make use of existing genetic resources for crop improvement and establishing effective evaluation networks, seed production systems, and seed delivery systems to ensure faster outreach and transformation.

• Molecules and Cells
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• 제20권1호
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• pp.136-141
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• 2005

Mild stresses such as high temperature ($30^{\circ}C$) or a low $H_2O_2$ concentration induced transient cell cycle arrest at G1/S or G2/M depending on the cell cycle stage at which the stress was applied. When stresses were introduced during G0 or G1, the G1/S checkpoint was mainly used; when stresses were introduced after S phase, G2/M was the primary checkpoint. The slowing of cell cycle progression was associated with transient delays in expression of A-, B-, and D-type cyclins. The delay in expression of NtcycA13, one of the A-type cyclins, was most pronounced. The levels of expression of Ntcyc29 (a cyclin B gene) and of CycD3-1 differed most depending on the applied stress, suggesting that different cellular adjustments to mild heat and a low concentration of $H_2O_2$ are reflected in the expression of these two cyclins.

• BMB Reports
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• 제42권7호
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• pp.439-443
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• 2009

Dehydrins are group II, late embryogenesis abundant proteins that act putatively as chaperones in stressed plants. To elucidate the function of dehydrins in poplar, we isolated the $SK_2$-type dehydrin gene Podhn from Populus alba $\times$ P. tremula var. glandulosa suspension cells and analyzed its expression following treatments of abiotic stress, wounding and plant growth regulator. Sequence homology and phylogenetic analyses indicate Podhn encodes an acidic dehydrin (pI 5.14, 277 amino acids, predicted size 25.6 kDa) containing two lysine-rich "K-segments" and a 7-serine residue "S-segment", both characteristic of $SK_2$-type dehydrins. Southern blots show Podhn genes form a small gene family in poplar. Podhn was expressed in all tissues examined under unstressed conditions, but most strongly in cell suspensions (especially in the stationary phase). Drought, salt, cold and exogenous abscisic acid (ABA) treatments enhanced Podhn expression, while wounding and jasmonic acid caused its reduction. Therefore, Podhn might be involved in ABA or stress response.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.167-172
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• 2007

A tomato zinc-finger protein gene, LeZFP1, encoding the Cys2/His2-type zinc-finger transcription factor was searched from cDNA microarray analysis of gene expression following induction of the overexpressed tomato transgenic plants showing resistance for pathogen and abiotic stresses. The full-length cDNA of LeZFP1 encoded a protein of 261 amino acid residues. Analysis of the deduced amino acid sequence of LeZFP1 revealed that it shares high sequence identity with pepper CAZFP1 (81% identity). We found that single copy of LeZFP1 gene is present in the tomato genome through southern blot analysis. The LeZFP1 transcripts were constitutively expressed in the tomato mature and young leaves, but were detectable weakly in the flower, stem and root. The LeZFP1 transcripts were significantly reduced in treated leaf tissues with NaCl and mannitol. The LeZFP1 gene was induced by oxidative stress especially. Our results indicated that LeZFP1 may play a role function involved in oxidative stress signaling pathways.