비타민A 강화벼와 ‘낙동’의 미꾸리(Misgurnus anguillicaudatus)와 잉어(Cyprinus carpio)에 대한 급성독성시험을 실시한 결과48시간 및 96시간-LC50은 1,000mg/L이상으로 나타났다. 48시간 및 96시간 무영향농도(NOEC)는 1,000mg/L이었다. 급성독성 시험기간 중 비타민A 강화벼와 낙동벼간의 pH, DO, 수온,체중 및 전장에 대한 유의적인 결과는 나타나지 않았다.

물벼룩 급성 독성 평가를 위한 비타민A 강화벼의 분자생물학적 특성을 분석한 결과, Southern blot에서 베타-카로틴 생합성을 위한 Psy와 CrtI 유전자들이 one-copy로 도입됨을 확인하였으며, 선발마커인 Bar 유전자의 단백질 검출 immunostrip 분석에서도 비타민A 강화벼에서만 검출되었다. 비타민A 강화벼의 목적하는 최종 산물인 베타-카로틴 함량도 낙동벼에 비해 8.9배 증가됨을 확인하였다. 비타민A 강화벼와 낙동벼의 농업환경 생물지표종인 물벼룩(Daphniamagna)에 대한 급성독성시험을 실시한 결과, 비타민A 강화벼의 48시간-EC50은 3,311.40 mg/L(95% 신뢰한계 : 2,901.39 ~ 3,779.23 mg/L), 무영 향농도(NOEC)는 1,800 mg/L였고, 낙동벼는 48시간-EC50은 3,655.23 mg/L(95% 신뢰한계 : 3,156.71 ~ 4,232.86 mg/L), 무영향농도는 1,800 mg/L였다. 따라서 Psy와 CrtI 유전자가 형질전환된 비타민A 강화벼 및 낙동벼가 환경 지표생물종인 물벼룩에 미치는 영향 평가 결과 상대적 동등성을 보였으며, 이는 Psy와 CrtI 유전자의 단백질 노출이 물벼룩에 부정적인 영향을 미치지 않은 것으로 판단된다.

해충저항성 Bacillus thuringiensis (Bt) 벼의 비표적곤충인 벼물바구미(Lissorhoptrus oryzophilus)에 대한 성충 전용살충제 Clothianidin 액상수화제의 살충제 감수성 시험을 실시한 결과, 72시간-LC50은 0.245 ml/L(95% 신뢰한계는 0.195~0.307 ml/L)이었으며, Bt벼의 모본으로 대조로 사용한 낙동벼의 72시간-LC50은 0.257 ml/L(95% 신뢰한계는 0.199~0.331 ml/L)이었다. 72시간-LC50은 낙동벼에서 다소 높았지만, 해충저항성 Bt벼 72시간-LC50이 낙동벼의 95% 신뢰한계 내에 포함되어, 두 품종의 LC50값에 유의성이 없는 것으로 판단된다.

해충저항성 Bt벼와 낙동벼의 미꾸리(Misgurnus anguillicaudatus) 와 잉어(Cyprinus carpio)에 대한 급성독성시험을 실시한 결과 48시간 및 96시간-LC50은 1,000mg/L 이상으로 나타났다. 48시간 및 96시간 무영향농도(NOEC)는 1,000mg/L이었다. 급성독성 시험기간 중 해충저항성 Bt벼와 낙동벼간의 pH, DO, 수온, 체중 및 전장에 대한 유의적인 결과는 나타나지 않았다.

본 연구의 목적은 방화곤충에 의해 유전자변형 작물로부터 비변형작물로의 유전자 이동이 일어날 수 있는가를 조사하기 위한 프로토콜을 개발하는 것이다. 이를 위해 제초제저항성 형질전환 콩과 재배콩인 태광콩, 그리고 G. soja 시험구에서 발생하는 곤충상을 sweeping법으로 조사하였으며, 이들 시험구에서 화분매개 가능성을 가진 방화벌의 시간대별 출현빈도 및 부위별 화분 부착율을 조사하였다. 또한 채집한 서양종꿀벌로부터 부착된 화분을 이용, 핵산을 추출하고 PCR 증폭 가능성 여부를 분석하였다. 그 결과, 유전자변형 콩과 비변형 콩 사이의 곤충상에는 시기별로 유의성 있는 차이는 없는 것으로 조사되었다. 개화기 콩 꽃에서 서양종꿀벌의 출현빈도는 정오에 가장 높은 것으로 나타났다. 이들이 수확한 화분으로부터 핵산을 추출하여 PCR 을 수행하였을 때 lectin 유전자가 증폭된 것으로 보아 이들 화분은 콩으로부터 유래한 것임을 확인하였다.

Genetically modified (GM) crops have been developed worldwide through the recombinant DNA technology and commercialized by various agricultural biotechnology companies. Commercialization of GM crops will be required the assessment of risk associated with the release of GM crops. The purpose of this research is a molecular characterization of introduced T-DNA in transgenic rice T4 ∼ T6 generation lines harboring a pepper MsrB2 gene under the control of stress inducible Rab21 promoter, as a part of biosafety evaluation for drought-tolerant transgenic rice (Agb0103). We identified the structure and sequence of transformation vector of T-DNA and analyzed insertion sites, flanking sequences, and generational stability of inserted T-DNA in transgenic rice lines. The transformation vector was consisted of right border, a drought-tolerant CaMsrB2 gene unit (Rab21 promoter::CaMsrB2::PinII terminator), a selectable marker herbicide resistance unit (CaMV 35S promoter::bar::Nos terminator), and left border in sequential order. Based on the adaptor-ligation PCR and whole genome sequence database, we confirmed that T-DNA was introduced 2 copies (head to head type) at the position of 2,471,957 ∼ 2,472,049 bp of chromosome No. 8. From the generational stability study, T-DNAs were stably inherited through the T4 to T6 generations, and also stable expression of bar gene from T-DNA was confirmed. It was also confirmed that the backbone DNA of transformation vector containing antibacterial gene (aadA) was not present in Agb0103 rice genome. These results will be filed to biosafety assessment document of Agb0103

The perturbation of the steady state of reactive oxygen species due to biotic and abiotic stresses in a plant could lead to protein denaturation through the modification of amino acid residues, including the oxidation of methionine residues. Methionine sulfoxide reductases (MSRs) catalyze the reduction of methionine sulfoxide back to the methionine residue. To assess the role of this enzyme, we generated transgenic rice using a pepper CaMSRB2 gene under the control of the rice Rab21 promoter with/without a selection marker, the bar gene. A drought resistance test on transgenic plants showed that CaMSRB2 confers drought tolerance to rice, as evidenced by less oxidative stress symptoms and a strengthened PSII quantum yield under stress conditions, and increased survival rate and chlorophyll index after the re-watering. The results from immunoblotting using a methionine sulfoxide antibody and nano-LC-MS/MS spectrometry suggest that porphobilinogen deaminase (PBGD), which is involved in chlorophyll synthesis, is a putative target of CaMSRB2. The oxidized methionine content of PBGD expressed in E. coli increased in the presence of H2O2, and the Met-95 and Met-227 residues of PBGD were reduced by CaMSRB2 in the presence of dithiothreitol. An expression profiling analysis of the overexpression lines also suggested that photosystems are less severely affected by drought stress. Our results indicate that CaMSRB2 might play an important functional role in chloroplasts for conferring drought stress tolerance in rice

Genetically modified (GM) crops have been developed worldwide through the recombinant DNA technology and commercialized by various agricultural biotechnological companies. Commercialization of GM crops will be required the assessment of risk associated with the release of GM crops. In this study, we carried out to provide the molecular characterization of introduced T-DNA in transgenic rice T4 ~ T6 generation lines harboring a pepper MsrB2 gene under the control of stress inducible Rab21 promoter, as a part of biosafety evaluation for drought-tolerant transgenic rice (CaMsrB2). We identified the structure and sequence of transformation vector of T-DNA and analyzed insertion sites, flanking sequences, and generational stability of inserted T-DNA in transgenic rice lines. The transformation vector was consisted of right border, a drought-tolerant CaMsrB2 gene unit, a selectable marker herbicide resistance unit, and left border in a sequential order. Based on the adaptor-ligation PCR and whole genome sequence database, we confirmed that T-DNA was introduced at the position of 41,737,284 bp of chromosome No. 1. From the generational stability study, T-DNAs were stably inherited through the T4 to T6 generations, and also stable expression of bar gene from T-DNA was confirmed. These results will be filed to biosafety assessment document of CaMsrB2 rice.

비타민A 강화벼의 복수세대에 대한 후대안정성을 Southern blot과 PCR로 분석한 결과, 비타민A 강화벼의 PAC T3～T6 세대에서는 도입된 모든 유전자들이 안정적으로 도입되어 있으며, backbone DNA는 비타민A 강화벼에 삽입되지 않았음을 확인하였다. 선발 마커로 도입된 PAT 단백질의 발현 분석 결과에서도 PAC T3～T6 복수세대에서 생육시기별 부위별로 안정적으로 발현됨을 입증하였으며, 최종 목적 산물인 카로티노이드 분석 결과에서도 모품종인 낙동벼에 비해 비타민A 강화벼에서 β-carotene은 10.6배 함량이 증가되고, zeaxanthin과 α-carotene는 생성되었음을 확인하였다. 이상의 분석기법을 통해 복수세대에서 비타민A 강화벼의 도입 유전자들이 안정적으로 유지되고 목적 단백질들이 안정적으로 발현되고 있음을 확인하였다.

The MYB transcription factors play important roles in the regulation of many secondary metabolites at the transcriptional level. We evaluated the possible roles of the Arabidopsis R2R3-MYB transcription factor genes in flavonoid biosynthesis as they are induced by UV-B irradiation but are largely unexplored in terms of their associated phenotypes. We found that one member of this gene family, AtMYB60, inhibits anthocyanin biosynthesis in the lettuce plant. Wild type lettuce normally accumulates anthocyanin, predominantly cyanidin and traces of delphinidin, and develops a red pigmentation. However, the accumulation of anthocyanin pigments in AtMYB60 overexpressing lettuce was inhibited. We further found a complete absence of DFR transcripts in AtMYB60 overexpressing lettuce, whereas other biosynthetic genes in the anthocyanin metabolism pathway were expressed. To provide genetic tools the regulation of seed color of rapeseed which has been target for fuel, AtMYB was overexpressed in rapeseed. Transgenic plants showed lighter seed color and improved tolerance to abiotic stress than the wild type plants. The elucidation of the roles of the AtMYB60 transcription factor will facilitate further studies and provide genetic tools to better understand the regulation in plants of the genes controlled by the MYB-type transcription factors.