• Journal of Plant Biotechnology
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• 제2권2호
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• pp.73-78
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• 2000

The plastid genomes of several plants contain ndh genes homologues of genes encoding subunits of the mitochondrial complex I. We sequenced the part of lupin ndhB, ndhD and ndhF genes in order to compare the structure of these genes with those of Nicotiana tabaum, Arabidopsis thaliana, Zea mays and Oryza sativa with the idea to detect the presence of stretches with identical aminoacid composition. We were only able to find one or two stretches of this kind of about 16 aminoacid- long in the analyzed fragments of the ndh genes. The total number of such stretches was different in particular gene products: for ndhc 1, ndhB 9, ndhD 3 and ndhF 6. We have also examined the transcription pattern of ndhC, ndhK and ndhJ genes during lupin development. We show that the greatest amount of ndhC, ndhK and ndhJ transcripts are observed in 7- to 14 day- old lupin seedlings. We also studied the level of transcription of those genes in plants growing at low temperature. All the data confirmed that the abundance of transcription of ndhC, ndhK, and ndhJ genes increased under chill conditions. It has to be noted that the level of transcription of the ndhC gene was higher than the other genes probably due to higher stability of this transcript.

• ALGAE
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• 제18권4호
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• pp.239-253
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• 2003

The morphotaxonomic characters of the genus Spirogyra were investigated to clarify their taxonomic category and the variation range among species on the basis of comparative morphological and numerical analyses by unialgal cultures and field samples collected from various freshwater habitats in Korea. 25 characters selected on morphological feature of the species were examined on 568 individuals for morphological comparisons and numerical analyses. Width, length and their length/width ratio of vegetative cell, shape of septum, chloroplast number, maximum width, width, length and their length/width ratio of female gametangium, length of male gametangium, size and shape of zygospore, and cell wall ornamentation of the spore showed a comparatively high vector in principal component analysis. In cluster analysis, 15 taxa analysed were divided into 8 major groups by the average taxonomic distance 1.0 level. Considering the morphology and numerical analysis, Spirogyra crassoidea could not be recognized as an independent species, therefore it was treated as a variety of S. ellipsospora. S. koreana (nom. invalidum), recognized as a new taxon, is under the investigation for its clear taxonomic category.

• Molecules and Cells
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• 제21권3호
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• pp.401-410
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• 2006

The plastid transformation approach offers a number of unique advantages, including high-level transgene expression, multi-gene engineering, transgene containment, and a lack of gene silencing and position effects. The extension of plastid transformation technology to monocotyledonous cereal crops, including rice, bears great promise for the improvement of agronomic traits, and the efficient production of pharmaceutical or nutritional enhancement. Here, we report a promising step towards stable plastid transformation in rice. We produced fertile transplastomic rice plants and demonstrated transmission of the plastidexpressed green fluorescent protein (GFP) and aminoglycoside 3′-adenylyltransferase genes to the progeny of these plants. Transgenic chloroplasts were determined to have stably expressed the GFP, which was confirmed by both confocal microscopy and Western blot analyses. Although the produced rice plastid transformants were found to be heteroplastomic, and the transformation efficiency requires further improvement, this study has established a variety of parameters for the use of plastid transformation technology in cereal crops.

• 한국식물병리학회지
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• 제10권2호
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• pp.83-91
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• 1994

Stem tissues of tomato plants (cv. Kwanyang) inoculated with Phytophthora capsici were examined by light and electron microscopy to compare early cytological differences between comaptible and incompatible interactions of tomatoes with the fungus. Twenty four hours after inoculation, the compatible isolate S 197 colonized severely the epidermis, cortex, and xylem vessels of stem tissue, whereas only few fungal cells colonized the stem tissues inoculated with the incompatible isolate CBS 178.26. Fragmented plasma membrane, distorted chloroplast, degraded cell wall, remnants of host cytoplasm were early ultrastructural features of the damaged host cell observed both in the compatible and incompatible interaction, a number of vesicles were distributed in the space between fungal cell walls and plasma membrane. The degradation of host cell walls by P. capsici was more pronounced in the compatible than the incompatible interactions. The incompatible interactions of tomato cells with P. capsici were characterized by formation of host cell wall apposition in the cortical parenchyma cells, indicating that the apposition of electron-dense material from the host cell walls may function as a plant defense reaction to the fungus. The fungal cells encased by wall appositions had abnormal cytoplasm and separated plasma membranes. The haustorium which formed from the fungal hyphae did not further penetrate through the host wall apposition and cytoplasmic aggregation, especially in the incompatible reactions. In contrast, the haustorium of the compatible isolate S 197 was not encased by wall appositions.

• 한국연초학회지
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• 제17권1호
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• pp.20-26
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• 1995

This study was carried out to obtain the basic data which include the change of the photosynthetic rate and protein content according to growth stage in the process of senescence of tobacco plant The photosynthetic rate was the maximum with 26.31$\mu$mol.CO2/m2.sec and stomatal resistance was the minimum with 0.2552cm/sec at 15th days after leaf emergence. However, after 50 days the photosynthesis was very little occurred. During leaf developments the number of chloroplast was increased and reached at the maximum at 25th days after emergence of leaf, thereafter, it was decreased gradually. The content of protein increased continuously and showed the highest value at 15th days after leaf emergence. The degradation rate of soluble protein was more rapid than that of insoluble protein at early stage of senescence. The range of decrement in the insoluble protein was low at late stage of senescence. The content of Rubisco, the key enzyme of photoamthesis, corresponded to about 50% of soluble protein and reached to the maximum at 150 days after leaf emergence. As the senescence progressed, the content of large subunit(UV) of Rubisco showed a tendency to decrease more rapidly than that of small subunit(SSU). The total amount of amino acids was the highest at 15th days after leaf emergence.

• Journal of Plant Biotechnology
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• 제1권2호
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• pp.101-107
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• 1999

The leaf blade-segments of albino tobacco (Nicotiana tabacum L.) were cultured on MS media containing different concentrations of BAP (0, 0.4, 2.2, 4.4, 22.2 ${\mu}{\textrm}{m}$) with or without NAA (0, 0.5, 2.7 ${\mu}{\textrm}{m}$). Multiple shoots were induced on the media containing 0.4 to 2.2 ${\mu}{\textrm}{m}$ BAP. The best condition for multiple shoot induction with root formation was MS media containing 4.4 ${\mu}{\textrm}{m}$ BAP and 0.5 ${\mu}{\textrm}{m}$ NAA. The regenerated albino plants showed a significant reduction in accumulation of chlorophylls and carotenoids. The drastic reduction of the pigments content was associated with the distinct alterations in gene expression in the albino plants. firstly, the expression of plastid genes, such as rbcL, psbA, 165 rDNA and 235 rDNA, was reduced at the level of transcripts in the regenerated albino plants. Secondly, the alteration of structure of the plastid genes was not detected in the albino plants. However, the copy number of the plastid genes whose transcription level was reduced greatly was increased approximately two-fold, although the transcriptions of nuclear gene (255 rDNA) showed the wild-type level.

• Journal of Plant Biology
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• 제29권1호
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• pp.41-51
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• 1986

The plants of Nicotiana tabacum L. cv. NC2326 were germinated in 10 cm D$\times$20 cm H polyethylene pot, and sand-cultured with Hoagland solution near by the window of laboratory room(26$\pm$5$^{\circ}C$). The growing plants were sprayed with various concentrations of ABA around 9 : 00 a.m. once in every two days for 12 weeks in summer. As the results, frequency of stomatal number, stomatal opening, chlorophyll content, respiration rate, and protein content in the leaves were decreased with the increasing of concentrations of ABA, respectively. The plant growth was inhibited by exogenous ABA, but leaf abscission was not found during the experimental period. The ratio of three to one in chlorophyll a to b was not altered by exogenous ABA. All the stomata were closed within three minutes by 100 $\mu\textrm{g}$ ml-1 ABA and within seven minutes by 1-10 $\mu\textrm{g}$ ml-1 ABA after the spraying of ABA, and then reopended after a few hours in 1-10 $\mu\textrm{g}$ ml-1 ABA and after 24 hours in 100 $\mu\textrm{g}$ ml-1 ABA. The polar movement of chloroplast within the guard cells was found in the higher concentrations of 10 and 100 $\mu\textrm{g}$ ml-1 ABA, but not found in the lower concentrations than 1 $\mu\textrm{g}$ ml-1 ABA. During the night and weak light, it was fond that the inhibition of respiration rate by the higher concentration of ABA was owing to firstly the stomatal closure by the spraying of ABA and secondly the decrease of stomatal frequency by the inhibition of stomatal development with exogenous ABA for the long period of 12 weeks. In the band number of leaf protein by the electrophoresis, most of the protein bands were disappeared by the higher concentration of 100 $\mu\textrm{g}$ ml-1 ABA, but were not altered by the lower concentration of ABA in comparison with control.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.187-187
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• 2022

Purple-discoloration of the uppermost leaves has been observed in some soybean cultivars in recent years. The purpose of this study was to characterize the novel phenotypic changes between the uppermost and middle leaves via multiple approaches. First, quantitative trait loci mapping was conducted to detect loci associated with the novel phenotype using 85 recombinant inbred lines (RILs) of the 'Daepung' × PI 96983 population. 180K SNP data, a major quantitative trait locus (QTL) was identified at around 60 cM of chromosome 6, which accounts for 56% of total phenotypic variance. The genomic interval is about ~700kb, and a list of annotated genes includes the T-gene which is known to control pubescence and seed coat color and is presumed to encode flavonoid 35-hydroxylase (F3'H). Based on Hyperspectral imaging, the reflectance at 528-554 nm wavelength band was extremely reduced in the uppermost leaves compared to the middle (green leaves), which is presumed die to the accumulation of anthocyanins. In addition, purple-discolored leaf tissues were observed and compared to normal leaves using a transmission electronic microscope (TEM). Base on observations of the cell organelles, the purple-discolored uppermost leaves had many pigments formed in the epidermal cells unlike the normal middle leaves, and the cell wall thickness was twice as thick in the discolored leaves. The thickness of the thylakoid layer in the chloroplast the number of starch grains, the size of starch all decreased in the discolored leaves, while the number of plastoglobule and mitochondria increased.

• 생명과학회지
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• 제21권10호
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• pp.1452-1459
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• 2011

귤나무속은 운향과(Rutaceae)에 속한다. 동남아시아, 미얀마, 중국 운남에서 기원된 것으로 알려져 있다. 이 속의 분류관계는 복잡한데 클론번식과 야생식물과 교잡이 빈번하다. 식물에서 속간 속내 계통관계 추론을 위해 널리 이용되고 있는 엽록체 trnL-trnF 부위가 있다. 이 귤나무속과 두 근연한 탱자나무속과 금감속에 속하는 7종간 계통 관계를 평가하였다. 많은 삽입이 발견되었고 속내 종간 변이는 결실/삽입에 의한 것으로 밝혀졌다. 이 속의 레몬과 당귤나무은 네 계통도(MP, ML, ME, and NJ)에서 모두 같은 분지군을 형성하여 가장 근연관계에 있었고 광귤나무(향귤나무)과 자매군을 형성하였다. 유자나무는 이들과 많은 서열 차이를 나타내었다. 외부 분지군은 낮은 지지도를 나타내었다.

• 한국초등과학교육학회지:초등과학교육
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• 제17권2호
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• pp.79-90
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• 1998

The purpose of this study is to investigate degree of the concept formation on cell in elementary school teachers and to clarify the patterns of their misconceptions. Data were collected by interview with 120 elementary school teachers, ranged from twenties to fifties in age, working in Taegu city. The instrument was developed by researchers and was categorized into four: cell as the basic units of life, morphology of cell, function of cell, growth of individual from the viewpoint of cell. The results are as follows: First, about 80% of teachers had two perspective outcome of cell: Cells are the basic units of life on earth. But the potato and meat, which we used to eat as food, are not constructed of cells but aggregated of nutrients. Second, most of elementary school teachers recognized that shapes of the cell in organisms were diverse, but some of them only could present several kinds of shape on cell. The 35% of teachers had misconception that shape of cell is all the same in a individual. It shows that this result is caused by lack of opportunity to observe the various kinds of cells. Third, most teachers understood tell can be seen only through a microscope. Yet in comparison with relative size, it was revealed that misconception of cell size was induced by the term of 'basic unit'. In addition, they thought that large organisms are built from large cells, and small organisms from small cells. Fourth, Elementary school teachers used to confuse the terms between chloroplast and chlorophyll, and believed that the genetic material was contained only in the reproductive cells and seeds. It was also revealed that they thought the nutrients such as starch and fat are located at intercellular space. Fifth, the 60% of teachers conceived correctly that growth of individual depends on mitosis and increase in cell number. The rest of them, however, misunderstood that it is due to the increase of tell volume.