RESEARCH ARTICLE: Ascorbate Peroxidase OsAPx1 is Involved in Seed Development in Rice

( Yeon Jeong Kim ),( Sung Il Kim ),( Markkandan Kesavan ),( Jun Soo Kwak ),( Jong Tae Song ),( Hak Soo Seo ) 한국육종학회 2015 Plant Breeding and Biotechnology Vol.3 No.1

Ascorbate peroxidases (APXs) are enzymes that detoxify peroxides such as hydrogen peroxide using ascorbate. They are distributed as isoenzymes in distinct cellular compartments, such as the cytosol, mitochondria and peroxisomes, where they play essential roles in scavenging reactive oxygen species (ROS) and protecting cells against the toxic effects of these species in higher plants, algae, euglena and other organisms. APXs also respond to environmental stresses, such as salinity and drought, and rice ascorbate peroxidase 1 (OsAPx1) participates in salinity tolerance. However, it is still unclear how OsAPx1 is involved in growth and development before and after flowering. Here, we show that OsAPx1 plays an important function in seed development, including fertilization. Proteomic analysis and quantitative RT-PCR showed that protein and mRNA levels of OsAPx1 were much higher in immature seeds than in mature seeds. Plant height and grain size in an Osapx1 mutant were almost the same as those in wild-type plants. However, about 58% of the seeds were aborted in the Osapx1 mutant, although the mutant was capable of normal flowering. Our results suggest that rice ascorbate peroxidase functions both as a regulator of seed development and as a scavenger of ROS.

저온 처리한 상추의 잎 내에서 ascorbate peroxidase와 dehydroascorbate reductase의 반응

강상재(Sang-Jae Kang) 한국생명과학회 2008 생명과학회지 Vol.18 No.12

상추식물에서 저온 처리를 하였을 때 저온 적응성 획득 메카니즘과 관련된 APX와 DHAR의 활성도와 mRNA 발현수준 등과의 관련성을 조사한 결과는 다음과 같다. 잎 조직 내 과산화수소의 함량은 일정하게 증가하다가 20℃에서 저온처리를 회복시키면 그 함량이 정상상태로 회복하는 경향을 보였으나 단백질의 함량은 반대의 경향을 나타내었다. 엽록소의 함량은 저온스트레스를 처리할 경우 엽록소 a와 b 및 총 엽록소의 함량이 점차 감소하는 경향을 보였으며 저온스트레스 회복 시 다시 증가하는 경향을 보였으나 카로티노이드 함량의 변화는 거의 일어나지 않고 일정한 수준을 유지하는 것으로 나타났다. 총 엽록소에 대한 엽록소a의 비율은 저온처리 12시간까지는 증가하다가 24시간 이후 급격하게 감소하게 되고 저온스트레스를 회복시켰을 때 정상 수준으로 회복되는 경향을 나타내었다. APX와 DHAR의 활성도는 저온 처리가 진행됨에 따라 상추의 잎 조직 내에서 급격하게 증가하는 경향을 보이고 있으나 적온으로 회복시키면 정상수준으로 유지되었다. 저온처리 시간이 경과함에 따라 APX와 DHAR의 mRNA의 발현 수준이 크게 증가하는 경향을 보였다가 원래 수준으로 회복되었다. APX의 활성도와 과산화수소의 함량과의 상관관계는 상추의 잎 조직 내 과산화수소의 함량이 증가하면 APX의 활성도가 증가하는 경향(R²=0.8715)을 보였으며, DHAR의 활성도와 과산화수소의 함량도 동일한 경향으로 증가(R²=0.8643)하였다. 그러나 과산화수소의 생성량이 증가함에 따라 엽록소의 함량과 단백질의 함량은 저온 스트레스처리로 과산화수소의 생성량이 증가하면 엽록소의 함량(R²=0.5021)과 수용성단백질의 함량과는 감소하는 경향(R²=0.8915)을 보였다. To investigate the relationship between cold stress and the activity of ascorbate peroxidase(APX), dehydroascorbate reductase (DHAR), mRNA expression level of two enzymes, hydrogen peroxide content was studied in lettuce leaves under stress condition imposed by cold stress at 4℃ for 24 hr in the dark and following recovery at 20℃ from cold stress. Hydrogen peroxide content increased gradually in lettuce leaves during cold stress, but decreased slightly following recovery from cold stress. Soluble protein content, however, decreased gradually during cold stress, and then rapidly returned to normal levels following recovery. Total chlorophyll content decreased gradually during cold stress, and then keep constant following recovery. The patterns of chlorophyll a and b content similar to that of total chlorophyll content, and carotenoid content didn't change. The ratio of chlorophyll a and total chlorophyll was increased during cold stress, but decreased with rapid during cold stress, and then the ratio returned to normal levels following recovery. During cold stress, the activity of APX and DHAR in the lettuce leaves increased dramatically, and also transcript levels of mRNA of APX and DHAR, as determined by probing <SUP>32</SUP>P-labeled single stranded RNA of APX and DHAR, highly increased and returned to normal levels following recovery, respectively. Relationship between APX and DHAR activity and hydrogen peroxide highly related (R²=0.8715 and 0.8643), whereas between hydrogen peroxide and total chlorophyll content and soluble content related reversely (R²=0.5021 and 0.8915).

가열 전처리에 따른 피망의 품질 특성 변화

황인국 ( In Guk Hwang ),김광일 ( Kwang Il Kim ),조연지 ( Yeon Ji Jo ),최미정 ( Mi Jung Choi ),민상기 ( Sang Gi Min ),유선미 ( Seon Mi Yoo ) 한국산업식품공학회 2015 산업 식품공학 Vol.19 No.2

본 연구에서는 피망의 동결 전 가열처리 조건을 선정하기 위해 열수침지, 과열증기 및 볶음 처리 조건에 따른 품질 특성 변화를 조사하였다. 피망의 외관, 색도, 경도, 미세구조 관찰 등의 결과로 각 방법별 두 가지 조건을 선정후 영양학적 품질 조사를 실시하였다. 가열처리 후 피망의 ΔE 값은 처리 시간에 따라 감소하는 경향을 보였고, 특히 볶음 처리시 감소폭이 큰 것으로 나타났다. 열수침지 및 과열증기 처리에 따른 pH 변화는 적었지만, 볶음 처리 후감소하였다. 경도는 가열처리 후 대체적으로 감소하는 경향을 보였고, 열수침지 및 볶음 처리 시간이 길수록 경도는 급격히 감소하는 경향을 보였다. 피망의 일반성분, 비타민 C, 유리당 및 유기산 함량은 가열처리 방법 및 처리 시간에 따라 유의적인 영향을 받았다. 비타민 C 함량은 열수침지>과열증기>볶음 처리 순으로, 처리 시간이 길수록감소량이 큰 것으로 나타났다. 피망의 수용성 성분인 유리당 및 유기산 함량은 볶음 처리에 비해 열수침지 및 과열증기 처리시 감소량이 많았다. Peroxidase 활성은 짧은 시간의 열수침지(2분) 및 과열증기(3분) 처리에도 약 90% 이상의 불활성화율을 나타냈지만, 볶음 처리시에는 peroxidase활성 억제 효과가 20% 이하로 낮았다. 이상의 결과로부터 피망의 가열처리 조건은 색도, 경도, 비타민 C, 유리당 등 변화는 적고 peroxidase 억제 효과가 높은 증기처리법으로 3분간 처리하는 것이 적합할 것으로 판단된다. The thermal pre-treatment is an important process to minimize quality change in main cooking or storage. This study was conducted to investigate the effect of different thermal pre-treatment methods (blanching, steaming, and stir-frying) on the quality properties of bell pepper (BP). Washed and sliced BP were treated by blanching (100oC, 1-10 min), steaming (100oC, 1-10 min), and stir-frying with oil (180oC, 10-70 sec). Raw and treated BP was measured for color, pH, hardness, proximate composition, ascorbic acid, free sugar, organic acid, and peroxidase activities. Color and hardness were significantly decreased by blanching, steaming, and stir-frying. Stir-frying, in particular, rapidly decreased the ΔE values and hardness of BP. Blanching and steaming slightly increased the pH compared with raw BP, whereas stir-frying rapidly decreased the pH values. Results showed that the proximate composition, ascorbic content, free sugar content, and organic acid content were significantly (p<0.05) affected by the thermal pre-treatment and that the loss rate varied among individual compounds. Blanching, steaming, and stir frying significantly reduced the ascorbic acid content (29.4-55.2%), fructose content (8.6-45.1%), and glucose content (8.1- 41.9%) in the BP. Oxalic acid, citric acid, succinic acid, and furmaric acid as organic acid in BP were detected and their contents were significantly (p<0.05) reduced during thermal pre-treatment. In conclusion, the results demonstrated that steam treatment for 3 min could be the best optimal thermal pre-treatment condition for BP to minimize the quality changes.

엽록체에 과발현된 PsAPX1 유전자 형질전환 벼의 다양한 환경스트레스 내성 증진

박향미,김율호,최만수,이재은,최인배,최임수,신동범,이장용,곽상수,권석윤 한국육종학회 2009 한국육종학회지 Vol.41 No.3

1. 본 연구에서는 완두유래의 세포질성 PsAPX1 유전자를 대상으로 산화스트레스 유도성 프로모터를 연결하여 엽록체에 targeting 되는 과발현 운반체를 제작하고 벼에 도입한 결과 형질전환체에서 도입유전자 수가 1~3 copy인 것으로 나타나, 적은 수의 유전자가 안정적으로 도입되었음을 확인하였다. 2. 염, 오존, 자외선, 한발과 같은 다양한 환경스트레스 조건에서 내성이 증진된 우수 계통을 선발하기 위하여 작성된 형질전환 벼 계통들을 대상으로 생물 Oxidative stress is a major damaging factor for plants exposed to environmental stresses. In order to develop transgenic rice plants with enhanced tolerance to various environmental stresses, PsAPX1, the gene of ascorbate peroxidase isolated from Pisum sativum was expressed in chloroplast under the control of an oxidative stress inducible sweet potato peroxidase2 (SWPA2) promoter (referred to as PsAPX1 plants). PsAPX1 transgenic plants showed enhanced tolerance to various environmental stresses, such as 170 mM NaCl, UV-B, ozone, 20% PEG, and drought in compared with non-transgenic (NT) plants. These results suggest that chloroplast-targeted over-expression of PsAPX1 gene could be very useful strategy for developing transgenic rice plants with increased tolerance to environmental stresses.

들깨 종자 활력 수준별 초저온 동결보존 후 발아율 및 Ascorbate Peroxidase 활성 변화

이영이,이명희,이정윤,이태윤,손은호,박홍재 한국환경농학회 2017 한국환경농학회지 Vol.36 No.4

식물 종자를 비롯한 각종 유전자원을 액체질소에 저장하면 유전형질 특성의 손실 없이 장기간 보존할 수 있다. 본 연구에서 보존조건이 까다로워 단명 종자로 분류되는 들깨 종자를초저온 동결저장 방법으로 보존할 수 있는지를 조사하였다. 수집한 들깨 품종별 종자의 초기 발아율은 40-95% 수준으로 다양하였는데, 수분함량을 3-8%로 조절한 종자를 액체질소에 처리하여도 발아율은 감소하지 않았다. 종자의 수분함량이 4-5%인 종자의 초저온 처리 후 발아율이 가장 높았으며, 초기 발아율이 낮은 품종에서는 초저온 처리에 의해 발아율이 증가하기도 했다. 인위 노화처리에 따라 종자의 발아율과ascorbate peroxidase 활성은 감소하였으며, 품종별로 종자의활력 저하 정도는 크게 달리 나타났다. 대조 처리 종자와 비교하였을 때, 초저온 처리과정에 발생할 수 있는 산화스트레스가 들깨 종자의 활력을 저해하지는 않을 것으로 추정되었다. 따라서 들깨 종자를 4-5% 수분함량으로 건조시켜 초저온동결 저장하면 활력 손실 없이 장기간 보존할 수 있을 것으로판단되며, 노화가 급속히 진행되는 품종의 경우에는 고활력자원을 확보하거나 휴면타파 처리 후 초저온 동결 보존하는것이 유리할 것으로 생각된다. BACKGROUND: Seed of perilla (Perilla frutescens var. japonica Hara) is short-lived in conventional storage conditions. For long-term conservation of plant species, cryopreservation is the method currently available. This study was performed to find out reliable methods for a long-term storage of seeds of perilla as a genetic resource. METHODS AND RESULTS: Using seeds of 9 perilla cultivars, the effects of desiccation, aging, andcryopreservation on seed germinability and ascorbate peroxidase activity in the seeds were investigated. Initial germinability of the seeds was various, and dry seeds of all cultivars survived cryopreservation without loss of viability. The highest germination was achieved at 4-5% moisture content, and stimulatory effect of cryogenic temperature on the seed germination was observed in some cultivars. Accelerated aging of perilla seeds led to reduction in germination and ascorbate peroxidase activity, and the susceptibility of seeds to aging was different among the tested cultivars. No significant difference in germination was observed for the aged seeds of control and liquid nitrogen exposed. CONCLUSION: The results of this study suggest that cryopreservation at 4-5% moisture content would be a suitablemethod for long-termconservation of perilla seeds without detrimental effects on germination.

Ascorbate Peroxidase 유전자의 도입에 의한 식물의 형질전환

이인애,이효신,배은경,김기용,이병헌,손대영,조진기 Plant molecular biology and biotechnology research 2002 Plant molecular biology and biotechnology research Vol.2002 No.-

This study was conducted to obtain the transformed tobacco (Nicotiana tubacum) plants with cytosolic ascorbate peroxidase gene(ApxSC7) using Agrobacterium tumefaciens LBA4404. A cDNA encoding the cytosolic ascorbate peroxidase of strawberry, ApxSC7, was introduced into tobacco plants via Agrobacterium-mediated gene transfer system. The expression vector, pIG-AP8, harboring ApxSC7 gene was used for production of transgenic tobacco plants. A large number of transgenic plants were regenerated on a medium containing hygromycin. Integration of ApxSC7 gene was confirmed by PCR and Southern blot analyses with genomic DNA. Northern blot analyses revealed that the pIGap8 gene was constitutively expressed.

Molecular Characterization and Expression Analysis of Ascorbate Peroxidase in Codonopsis lanceolata (S. et Z.) Trautv

In Jun-Gyo,Lee Eun-Kyung,Kim Ha-Na,Yoon Jae-Ho,Lee Mee-Sook,Yang Deok-Chun 한국자원식물학회 2005 Plant Resources Vol.8 No.3

A cytosolic ascorbate peroxidase, hydrogen peroxide-scavenging enzyme, was characterized from Codonopsis lanceolata. The cytosolic ascorbate peroxidase cDNA (CAPX) was 983 nucleotides long and possess an open reading frame of 753 bp with 251 amino acids (MW 27.9 kDa) with pI 5.61. The deduced amino acid sequence of CAPX shows high homology to other known cytosolic APXs (78~83%, but the CAPX was clustered independently from compared ten plant APXs. The CAPX gene was highly expressed in leaf and stem tissues, but not in root. When Codonopsis leaves cut using scalpel were soaked in 1 mM hydorgen peroxide, the expression of CAPX gene was suppressed.

Expression Analysis of Oryza sativa Ascorbate Peroxidase 1 (OsAPx1) in Response to Different Phytohormones and Pathogens

Yiming Wang(왕이밍),Jingni Wu(우징니),Young Whan Choi(최영환),Tae Hwan Jun(전태환),Soon Wook Kwon(권순욱),In Soo Choi(최인수),Yong Chul Kim(김용철),Ravi Gupta(라비굽타),Sun Tae Kim(김선태) 한국생명과학회 2015 생명과학회지 Vol.25 No.10

본 논문에서 벼 ascorbate peroxidase (OsAPx1) 유전자의 발현 분석을 Northern과 Western 분석을 통하여 유묘에서는 뿌리, 정단분열조직(shoot apical meristem, SAM), 잎 보다는 잎집에서 더 많이 발현되는 것을 확인하였다. 성숙된 조직에서는 OsAPx1 유전자가 잎을 제외하고는 뿌리, 줄기, 꽃에서 강하게 발현되었다. 또한 이 OsAPx1 유전자는 벼 곰팡이 병원균인 벼 도열병 및 세균성 병원균인 흰빛잎마름병에도 반응하였고 특히 흥미있게도 OsAPx1 유전자는 식물호르몬에 대해서 서로 다르게 발현 양상을 보였다. 이 유전자는 자스몬산(JA)에 대해서는 강한 발현을 보였지만 반대로 살리실산(SA) 및 ABA와 같이 처리된 세포에서는 강한 발현 억제를 보였다. 이는 이 유전자가 JA에는 반응하지만 SA와 ABA하고는 서로 길항작용을 하는 것으로 보인다. 근연관계분석을 통하여 OsAPx1유전자가 애기장대의 AtAPx1 와 거의 유사하여 AtAPx1 결손 라인을 가지고 표현형 조사를 실시하였다. 그 결과, 외부에서 H₂O₂를 처리하였을 때에 O₂<SUP>-</SUP> 와 H₂O₂의 축적이 wild type과 비교하여 AtAPx1 결손 라인에서는 현저히 높았다. 따라서 본 연구를, 통하여 OsAPx1 유전자는 벼에서 산화 환원 균형 유지를 통하여 다양한 세포 분화발달 및 병원균 방어에도 관여하며 이 유전자의 발현은 JA의 신호전달에 의해서 매개되는 것으로 예상이 된다. We have isolated and characterized an ascorbate peroxidase (APx) gene, OsAPx1 from rice. Northern and Western blot analyses indicated that at young seedling stage, OsAPx1 mRNA was expressed highly in root, shoot apical meristem (SAM) and leaf sheath than leaf. In mature plant, OsAPx1 gene expressed highly in root, stem and flower but weakly in leaf. OsAPx1 gene and protein expression level was induced in leaves inoculated with Magnaporthe oryzae (M. oryzae) and Xanthomonas oryzae pv. oryzae (Xoo). Phytohormones treatment showed that OsAPx1 was up-regulated by jasmonic acid (JA), but was down regulated by ABA and SA co-treatments with JA, resulting that they have antagonistic effect on pathogen responsive OsAPx1 expression. Phylogenetic analysis illustrated that Arabidopsis AtAPx1 has a close relationship with OsAPx1. In AtAPx1 knock out lines, the accumulation of O₂<SUP>-</SUP> and H₂O₂ are all highly detected than wild type, revealing that the high concentration of exogenous H₂O₂ cause the intercellular superoxide anion and hydrogen peroxide accumulation in AtAPx1 knockout plant. These results suggested that OsAPx1 gene may be associated with the pathogen defense cascades as the mediator for balancing redox state by acting ROS scavenger and is associated with response to the pathogen defense via Jasmonic acid signaling pathway.

Effect of Silicon on Growth and Tolerance of Torenia fournieri In Vitro to NaCl Stress

Eun Hye Jo,Prabhakaran Soundararajan,Yoo Gyeong Park,Byoung Ryong Jeong 한국화훼학회 2018 화훼연구 Vol.26 No.2

The beneficial effect of silicon (Si) in increasing salt stress tolerance has been observed in many plants, including the cereal crops rice, wheat, and barley. In this experiment, we examined the effect of Si on the survival and growth of torenia (Torenia fournieri L inden ex F oum) ‘ Duchess Blue and White’ cultured in vitro in the presence and absence of salt stress. Previous reports had suggested that torenia exhibited low salt tolerance. Shoot buds isolated from 16-day-old seedlings were cultured on Murashige and Skoog (MS) medium containing 0, 50, or 100 mM NaCl alone or in combination with 1.8 or 3.6 mM Si supplied as K2SiO3. Plant survival rate was significantly reduced by NaCl supplementation compared with the control. The survival rate significantly increased to 100% when 1.8 or 3.6 mM Si was added to the MS medium containing 50 mM NaCl. However, only 31% of plantlets survived when 1.8 mM Si was added to the culture medium containing 100 mM NaCl. Shoot and root lengths significantly decreased with increasing NaCl concentration in the culture medium, whereas addition of NaCl to the MS medium also significantly reduced fresh and dry weights. However, Si supplementation significantly increased fresh and dry weights under 50 mM NaCl, compared with the control. The greatest fresh and dry weights were recorded when shoot buds were cultured on MS medium containing 50 mM NaCl and 3.6 mM Si. The activities of the antioxidant-scavenging enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT), but not peroxidase (POD), were markedly higher in the presence of 50 mM NaCl than the activity of the control. When Si was added to the medium containing 50 mM NaCl, activities of SOD, POD, APX, and CAT decreased as compared with the 50 mM NaCl treatment. Thus, Si-mediated tolerance to NaCl stress was not due to increased activity of antioxidant enzymes. Although Si was not effective in increasing tolerance to high salt concentrations, such as 100 mM NaCl, the results suggested that Si supplementation could effectively enhance tolerance to 50 mM NaCl stress.

오존 스트레스에 대한 몇 수종의 생장, 광합성, Ascorbate peroxidase 활성반응

우수영 ( Su Young Woo ),이성한 ( Sung Han Lee ),권기원 ( Ki Won Kwon ),이재천 ( Jae Cheon Lee ),최정호 ( Jeong Ho Choi ) 한국산림과학회 2004 한국산림과학회지 Vol.93 No.5

The purpose of this study was to identify the effects of ozone pollution on the 3 tree species in controlled environment. Ailanthus altissima, Liriodendron tulipifera, and Platanus occidentalis seedlings were examined in both control and ozone chambers to investigate growth, photosynthesis, and antioxidant enzymes such as Ascorbate peroxidase(APX). Ozone was fumigated 8 hours/day for 34 days with 150 ppb concentration. Photosynthesis of Platanus occidentalis was higher than those of Ailanthus altissima and Liriodendron tulipifera. APX activities of 3 tree species exposed in ozone chamber were higher than those of control in every measurement. It is a typical compensatory strategy of trees of stressed environment.