• Journal of Plant Biology
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• 제34권3호
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• pp.245-251
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• 1991

In order to investigate the phenolic compounds inducing the expression of Ti-plasmid vir genes of Agrobacterium tumefaciens KU12, we tested whether the eighteen phenolic compounds known as vir gene inducer have the activity to induce vir operon of the Ti-plasmid in A. tumefaciens KU12 transformed with pSM358cd. Also, the phenolic compounds in some tumor-uninduced dicotyledons and the attachment ability of a. tumefaciens KU12 on such dicotyledonous plants were investigated in an effort to analyze the reason why no tumor is formed on the plants. As results, fifteen among eighteen phenolic compounds known as vir gene inducer induced the expression of the Ti-plasmid vir genes. Some dicotyledonous plants which do not form the tumor have the phenolic compounds inducing the vir genes, but have less ability of the attachment than the dicotyledonous plants forming tumor.

• Journal of Plant Biology
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• 제39권3호
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• pp.179-184
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• 1996

The purpose of this study is to obtain the most efficient combination of Agrobacterium tumefaciens strains and Ti plasmids for the construction of dicotyledonous plant vector system. Ti plasmid-curing A. tumefaciens A136 and KU12C3 were transformed with four kinds of Ti plasmids, pTiBo542, pTiA6, pTiKU12 and pTiAch5, respectively. The stems of 28 species of dicotyledonous plants were then inoculated with these transformants and examined for crown gall formation. The different combination of A. tumefaciens strains and Ti plasmids showed quite a difference in terms of the crown gall formation. Agrobacterium strins A136 and KU12C3 have a same plant host range in case that both strains harour the same kind of Ti plasmid, pTiBo542 or pTiAch5. However, the above-mentioned both strains have quite different host range in the event of containing the same Ti plasmid, pTiKU12 or pTiA6. In case that KU12C3 contains pTiA6 or pTiKU12, this strain has a wider plant host range than A136. The plant host range of pTiBo542 is the widest, followed by pTiA6, pTiKU12 and pTiAch5. Twelve plants among 28 tested plants are not transformed by any virulent Agrobacterium strains used in this study. In conclusion, A. tumefaciens KU12C3 and A136 harboring pTiBo542 showed the widest host range for transforming dicotyledonous plants. Also, it was acertained that the host range of Ti plasmids is affected by chromosomal level.

• Journal of Plant Biology
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• 제33권2호
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• pp.97-104
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• 1990

In order to investigate the host range of Agrobacterium tumefaciens KU12 containing pTi-12, 28 species of dicotyledonous plants were infected with KU12, A136 without Ti plasmid and A348 containing pTi A6, respectively. KU12 and A348 induced tumor in 20 species and 14 species, respectively. This results showed that KU12 has a wide host range. Therefore, it was confirmed that KU12 and pTi-12 are very useful for developing plant vector system having a broad host range.

• 한국환경생태학회지
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• 제35권1호
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• pp.1-23
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• 2021

본 연구에서는 강원도 양구군에 위치한 숫돌봉(508m), 성주봉(625.3m), 수리봉(596.2m) 지역을 중심으로 식물상 조사를 실시하였다. 3개 산지 식물상 조사결과, 84과 255속 350종 4아종 43변종 6품종으로 총 403분류군의 관속식물이 조사되었다. 분류군별로는 양치식물이 5과 18분류군, 나자식물이 1과 3분류군, 쌍자엽식물이 69과 302분류군, 단자엽식물이 9과 80분류군으로 확인되었다. 주요 식물은 특산식물이 은사시나무, 키버들, 세잎승마, 진범, 등 총 11분류군, 산림청 지정 희귀식물은 위기종(EN) 개느삼 등 1종 취약종(VU) 세잎승마, 삼지구엽초, 솔나리 등 총 4분류군이 확인되었다. 약관심종(LC) 도깨비부채, 가침박달, 태백제비꽃 등 총 13분류군이 확인되었다. 침입외래식물은 털여뀌, 소리쟁이, 미국자리공, 유럽점나도나물, 흰명아주, 좀명아주, 족제비싸리, 아까시나무, 붉은토끼풀, 토끼풀, 들괭이밥, 애기땅빈대, 달맞이꽃 등 총 28분류군으로 조사되어, 조사식물 403분류군의 6.9%를 차지하였다.

• Rapid Communication in Photoscience
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• 제3권3호
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• pp.53-55
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• 2014

The shade avoidance syndrome is a morphological and physiological response when plants are exposed to shade. Recent work in Arabidopsis had begun to define the molecular components of the shade avoidance syndrome in dicotyledonous model plant. However, little is known about the shade avoidance response networks in agriculturally important monocotyledon crops such as rice. Here, we found that the degree of bending at the lamina joint is inversely proportional to the R:FR ratio. To elucidate which phytochrome is involved in this response, we did lamina joint inclination assay with the rice phytochrome-deficient mutants (osphyA, osphyB, and osphyC) and the wild type plants. Whereas the osphyA and osphyC knockout mutants bent at the lamina joint in the far-red rich condition as the wild type plants, the osphyB knockout mutants no longer bent at the lamina joint in the far-red rich condition. These results suggest that PHYB acts as a sole photoreceptor in the lamina joint inclination response in rice.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 심포지엄
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• pp.98-98
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• 2002

In higher dicotyledonous plants, the floral organs are arranged in four different whorls, containing sepals, stamens and carpels. petals, stamens and carpels. The specification of floral organ identity is explained by the ABC model (Weigel and Meyerowitz 1994). expression of an A-function gene specifies sepal formation in whorl 1. the combination of A-and B-function genes specifies the formation of petals in whorl 2, B-and C-function genes spesify stamen formation in whorl 3, and expression of the C-function alone determines the formation of carpels in whorl 1. A-, B-, C-function genes have been isolated from many plant species and most of them belong to the family of MADS-box genes encoding transcription factor. In contrast to the flower of higher dicots, the perianths of genseng plants have three whorls of almost identical petaloid organs. van Tunen et al. (1993) proposed a modified ABC model, exemplified with tulip. In this model, B-function genes are expressed in whorl 1 as well as whorl 2 and 3, theefore the organs of whorl 1 and whorl 2 have the same petaloid structure. They proposed this model with the molphological data of wild type and mutant flowers of tulip, however, there are no molecular data. To date, B-function genes were isolated several grass plants, rice, wheat and maize. However, grass plants have highly derived flowers, without well-developed perianths. To find out how the ABC model has to be modified for the Genseng plants, we have cloned and characterized orthologs of A-, B-, C-function genes from genseng.

• 한국육종학회지
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• 제42권5호
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• pp.455-462
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• 2010

Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate ($P_i$). The expression was organ-specific with the strongest expression in $P_i$-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient $P_i$ uptake and can be used to develop new transgenic dicotyledonous plants.

• 한국농림기상학회지
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• 제15권2호
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• pp.85-101
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• 2013

본 연구는 논, 밭, 과수원, 도로변에 생육하고 있는 식물상을 조사하여 $C_4$식물의 분포특성을 규명하고자 하였다. 현장조사는 2002년부터 2006년까지 5년간 수행되었다. 그 결과, 총 74과 231속 352종이 확인되었으며, 쌍자엽식물 255종, 단자엽식물 89종, 양치식물 8종으로 분류되었다. 농경지유형별로는 논에서 55과 203종, 밭에서 49과 218종, 과수원에서 44과 115종, 도로변에서 48과 202종이 출현하였다. 본 조사를 통하여 논은 쑥과 고마리, 밭과 도로변은 쑥과 개망초, 과수원은 닭의장풀과 바랭이로 대표되며 농업생태계에서 출현율이 가장 높은 식물은 쑥으로 확인되었다. 또한, 출현식물 중 $C_4$식물은 8과 25속 38종으로 확인되었으며, 논, 과수원, 도로변에서는 $C_4$ 단자엽식물의 출현율이 높았으며 밭에서는 다른 농경지유형에 비해 쌍자엽식물의 출현빈도가 높았다. 이러한 $C_4$식물의 출현율 차이는 고온 건조한 우리나라 밭 주변 식물서식환경을 반영하고 있으며, 논과 과수원은 상대적으로 습윤한 미기후조건에서 건조조건이 아니라 온도조건에 의해 $C_4$ 단자엽식물이 분포하는 것으로 생각되었다. 또한 농업생태계를 대표하는 $C_4$식물 중 단자엽식물은 바랭이와 닭의장풀이며 쌍자엽식물은 개비름과 명아주로 확인되었다. 본 조사에서 총 47종의 귀화식물이 확인되었으며 토양의 수분환경조건이 상대적으로 건조한 밭과 도로변에서 많은 귀화식물이 출현하였다. 귀화식물 가운데 $C_4$ 식물은 비름속의 개비름과 털비름 2종으로 나타났으며, 단자엽식물은 관찰되지 않았다. 본 연구에서는 농경지유형에 따른 대표적인 $C_4$식물의 분포특성이 확인되었으며 지구온난화로 인한 기온의 상승으로 고온에 적응성이 높은 $C_4$식물의 새로운 유입과 이미 유입된 종 가운데 농업생태계에 나쁜 영향을 미칠 수 있는 외래식물의 확산에 대한 장기적인 모니터링의 필요성을 제안하였다.

• Journal of Plant Biotechnology
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• 제43권1호
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• pp.30-36
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• 2016

Brassinosteroids (BRs) are essential plant steroid hormones required for cell elongation, plant growth, development and abiotic and biotic stress tolerance. BRs are recognized by BRI1 receptor kinase that is localized in the plasma membrane, and the BRI1 protein will eventually autophosphorylate in the intracellular domain and transphosphorylate BAK1, which is a co-receptor in Arabidopsis thaliana. However, little is known of the role OsBRI1 receptor kinase plays in Oryza sativa, monocotyledonous plants, compared to that in Arabidopsis thaliana, dicotyledonous plants. As such, we have studied OsBRI1 receptor kinase in vitro and in vivo with recombinant protein and transgenic plants, whose phenotypes were also investigated. A OsBRI1 cytoplasmic domain (CD) recombinant protein was induced in BL21 (DE3) E.coli cells with IPTG, and purified to obtain OsBRI1 recombinant protein. Based on Western blot analysis with phospho-specific pTyr and pThr antibodies, OsBRI1 recombinant protein and OsBRI1-Flag protein were phosphorylated on Threonine residue(s), however, not on Tyrosine residue(s), both in vitro and in vivo. This is particularly intriguing as AtBRI1 protein was phosphorylated on both Ser/Thr and Tyr residues. Also, the OsBRI1 full-length gene was expressed in, and rescued, bri1-5 mutants, such as is seen in normal wild-type plants where AtBRI1-Flag rescues bri1-5 mutant plants. Root growth in seedlings decreased in Ws2, AtBRI1, and 3 independent OsBRI1 transgenic seedlings and had an almost complete lack of response to brassinolide in the bri1-5 mutant. In conclusion, OsBRI1, an orthologous gene of AtBRI1, can mediate normal BR signaling for plant growth and development in Arabidopsis thaliana.

• 생명과학회지
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• 제18권4호
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• pp.488-493
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• 2008

Phosphate, a favorable phosphorous form for plant, is one of major nutrient elements for growth and development in plants. Plants exhibit various physiological and biochemical responses in reaction to phosphate starvation in order to maintain phosphate homeostasis. Of them, expression of high affinity phosphate transporter gene family and efficient uptake of phosphate via them is a major physiological process for adaption to phosphate deficient environment. Although the various genetic resources of high affinity phosphate transporter are identified recently, little is known about their functions in plant that is prerequisite information before applying to crop plants to generate valuable transgenic plants. We demonstrated that Arabidopsis transgenic plants over-expressing two different high affinity phosphate transporter gens, OsPT1 and OsPT7, derived from rice, exhibit better growth responses compared with wild-type under phosphate starvation condition. Specially, OsPT7 gene has proven to be more effective to generate Arabidopsis transgenic plant tolerant to phosphate deficiency than OsPT1. Furthermore, the expression level of AtPT1 gene that is one of reporter genes specifically induced by phosphate starvation was significantly low compared with wild-type during phosphate starvation. Taken together, these results collectively suggest that over expression of OsPTl and OsPT7 genes derived from monocotyledonous plant function efficiently in the dicotyledonous plant, relieving stress response caused by phosphate starvation and leading to better growth rate.