• 한국수학교육학회지시리즈E:수학교육논문집
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• 제36권1호
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• pp.39-57
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• 2022

본 연구는 맥락에서 출발하여 추상화로 나아가는 방식으로 수학 학습을 설명하는 AiC(Abstraction in Context) 이론에 따른 수업이 부정적분과 정적분의 관계에 대한 이해를 촉진하는 지를 파악하는 데 목표를 둔다. 이를 위해 과학고등학교 2학년 학생 8명을 대상으로 설계한 적분 지도 방안에 따라 수업을 실시했으며, 전 수업 과정을 녹화, 녹음한 자료와 활동지 등의 자료를 수집하고 분석하였다. 분석 결과, 연구에 참여한 학생들은 누적 개념이 내재된 맥락에서 출발하여 동료 학생들과 상호 소통하면서 부정적분과 정적분의 관계에 연결되는 세 가지 지식 요소인 '누적함수의 순간 변화율', '부정적분을 이용한 정적분의 계산', '누적함수를 이용한 부정적분의 결정'을 구성하였다. 연구결과를 바탕으로, AiC 관점은 부정적분과 정적분 관계의 학습을 지원하는 잠재력을 가지고 있으며, 이를 다른 학습영역으로 확장하여 고등학교 수학수업을 개선하는 데에도 활용할 수 있음을 논의하였다.

• Plant Resources
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• 제1권1호
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• pp.6-12
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• 1998

The Fp1 gene, originally isolated from red pepper seedlings, encode the iron storage protein, and have a high homology with ferritin genes at DNA and amino acid level. In order to determine ferritin protein expression in vegetative tissue. Fp1 gene was constructed in plant expression vector(PIG12IHm) and introduced in red pepper(var. Bukang, Chungyang and Kalag-Kimjang 2) via Agrobacterium tumefaciensmediated transformation. After selection on MS media containing Kanamycin(Km), putatively selected transformants were confirmed by amplification of selectable marker gene(Fp1 and NPII) by polymerase chain reaction. Northern blot showed that transcripts of Fp1 gene were detected in mature leaves of the plants. In A6, A7 and A8 and A14 of transgenic plants, transcript of Fp1 gene was increased seven-fold to eight-fold than other transgenic plants. Also the proteins obtained from leaves of transgenic plants were immunologically detected by Western blot using rabbit anti-ferritin polyclonal antibody. The expression protein appeared as strong band of apparent mass of 23.5kDa. suggesting the iron accumulation in transgenic red pepper plants.

• The Plant Pathology Journal
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• 제22권2호
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• pp.139-146
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• 2006

The 3' region of Potato virus X (PVX) has the 74 nt 3'-nontranslated region (NTR) that is conserved among all potexviruses and contains several cis-acting elements for minus-strand and plus-strand RNA accumulation. Three stem-loop structures (SL1-SL3), especially formation of SL3 and U-rich sequence of SL2, and near upstream elements in the 3' NTR were previously demonstrated as important cis-acting elements. To Investigate the binding of these cis-acting elements within 3' end with host protein, we used the electrophoretic mobility shift assays (EMSA) and UV-cross linking analysis. The EMSA with cellular extracts from tobacco and RNA transcripts corresponding to the 150 nt of the 3' end of PVX RNA showed that the 3' end of PVX formed complexes with cellular proteins. The specificity of protein binding was confirmed through competition assay by using with 50-fold excess of specific and non-specific probes. We also conducted EMSA with RNAs containing various mutants on those cis-acting elements (${\Delta}10$10, SL3B, SL2A and ${\Delta}21$; J Mol Biol 326, 701-720) required for efficient PVX RNA accumulation. These analyses supported that these cis-acting elements are required for interaction with host protein(s). UV-cross linking analysis revealed that at least three major host proteins of about 28, 32, and 42 kDa in mass bound to these cis-elements. These results indicate that cis-acting elements from 3' end which are important for minus and plus-strand RNA accumulation are also required for host protein binding.

• BMB Reports
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• 제43권2호
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• pp.103-109
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• 2010

Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

• Plant Biotechnology Reports
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• 제3권3호
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• pp.225-241
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• 2009

We investigated the transcriptional profiles of Japanese indigenous grape cultivar 'Koshu' (Vitis vinifera) leaf and berry skin during ripening. In leaf, 64 genes were abundantly transcribed at the end of $v{\acute{e}}raison$ (14 weeks post-flowering), whereas the expression of 61 genes was upregulated at the end of ripening (20 weeks post-flowering). In berry skin, 67 genes were abundantly transcribed at the end of $v{\acute{e}}raison$, whereas the expression of 86 genes was upregulated at the end of ripening. Gene expression associated with biological processes was activated in both tissues at the end of ripening. The expression of genes associated with photosynthesis, sugar synthesis, anthocyanin synthesis, cinnamic acid synthesis, and amino acid metabolism was observed in leaf and berry skin during ripening, together with the accumulation of sugars, anthocyanins, cinnamic acids, and amino acids. Transcripts of AUX/IAA family proteins that repress the activities of auxin-induced proteins were expressed in berry skin at the end of $v{\acute{e}}raison$. Transcripts of genes related to the ubiquitin-proteasome system that degrades AUX/IAA family proteins were abundantly expressed in berry skin at the end of ripening, suggesting that the expansion of skin cells at $v{\acute{e}}raison$ is suppressed by AUX/IAA family proteins, and that the ubiquitin-proteasome system induces the expansion of skin cells during ripening by degrading AUX/IAA family proteins. These transcriptional profiles, which provide new information on the characteristics of 'Koshu' grapevine during ripening, may explain the unique characteristics of 'Koshu' grape in comparison with those of European grapes used for winemaking, and may contribute to the improvement of 'Koshu' grape quality.

• Plant Biotechnology Reports
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• 제4권2호
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• pp.149-155
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• 2010

Expression of the genes for carotenoid bio-synthesis (crt) is dependent on light, but little is known about the underlying mechanism of light sensing and signalling in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter, Synechocystis). In the present study, we investigated the light-induced increase in the transcript levels of Synechocystis crt genes, including phytoene synthase (crtB), phytoene desaturase (crtP), ${\zeta}$-carotene desaturase (crtQ), and ${\beta}$-carotene hydroxylase (crtR), during a darkto-light transition period. During the dark-to-light shift, the increase in the crt transcript levels was not affected by mutations in cyanobacterial photoreceptors, such as phytochromes (cph1, cph2 and cph3) and a cryptochrome-type photoreceptor (ccry), or respiratory electron transport components NDH and Cyd/CtaI. However, treatment with photosynthetic electron transport inhibitors significantly diminished the accumulation of crt gene transcripts. Therefore, the light induction of the Synechocystis crt gene expression is most likely mediated by photosynthetic electron transport rather than by cyanobacterial photoreceptors during the dark-to-light transition.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.100.2-101
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• 2003

The global regulator, GacS (global antibiotic and cyanide sensor kinase), was required for the increased resistance to hydrogen peroxide occurring as cultures of the rhizobacterium, P. chlororaphis O6, matured. Specific stationary-phase peroxidase and catalase isozymes were absent in the GacS mutant, whereas a manganese-superoxide dismutase isozyme was expressed earlier and to a great extent than wild type. In the wild type cell, transcript accumulation of rpoS was higher in late logarithmic-phase cells than cells from mid logarithmic- or stationary-phase. Transcripts from rpoS in the GacS mutant were reduced in each of these growth phases compared to the wild type expression. The down stream sequence from rpoS lacked sequences encoding a small RNA, rsmZ, found in other pseudomonads and implicated in control of genes activated by the GacS system. These findings suggest that GacS-mediated regulation of RpoS plays role in control of oxidative stress in P. chlororaphis O6 by as yet an unknown mechanism.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1510-1517
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• 2008

Expresssed sequence tag (EST) analysis was developed from three cDNA libraries constructed from cells of the digestive tract, gonad, and liver of sea squirt. Randomly selected cDNA clones were partially sequenced to generate a total of 922 ESTs, in which 687 unique ESTs were identified respectively. Results of BLASTX search showed that 612 ESTs (89%) have homology to genes of known function whereas 75 ESTs (11%) were unidentified or novel. Based on the major function of their encoded proteins, the identified clones were classified into ten broad categories. We also identified several kinds of immune-related genes as identifying novel genes. Sequence analysis of ESTs revealed the presence of microsatellite-containing genes that may be valuable for further gene mapping studies. The accumulation of a large number of identified cDNA clones is invaluable for the study of sea squirt genetics and developmental biology. Further studies using cDNA microarrays are needed to identify the differentially expressed transcripts after disease infection.

• 한국초지조사료학회지
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• 제38권3호
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• pp.170-174
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• 2018

Environmental stresses caused by climate change, such as high temperature, drought and salinity severely impact plant growth and productivity. Among these factors, high temperature stress will become more severe during summer. In this study, we examined physiological and molecular responses of maize plants to high temperature stress during summer. Highest level of $H_2O_2$ was observed in maize leaves collected July 26 compared with June 25 and July 12. Results indicated that high temperature stress triggers production of reactive oxygen species (ROS) in maize leaves. In addition, photosynthetic efficiency (Fv/Fm) sharply decreased in leaves with increasing air temperatures during the day in the field. RT-PCR analysis of maize plants exposed to high temperatures of during the day in field revealed increased accumulation of mitochondrial and chloroplastic small heat shock protein (HSP) transcripts. Results demonstrate that Fv/Fm values and organelle-localized small HSP gene could be used as physiological and molecular indicators of plants impacted by environmental stresses.

• The Plant Pathology Journal
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• 제28권1호
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• pp.75-80
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• 2012

$Potato$ $virus$ $X$ (PVX) contains $cis$-acting elements including stem-loop 1 (SL1) RNA at the 5' region; SL1 is conserved among all potexviruses. The SL1 at the positive-sense RNA, SL1(+), is required for PVX RNA replication, cell-to-cell movement, and translation. Previous research demonstrated that SL1(+) RNA also serves as the origin of assembly for encapsidation of PVX RNA. To identify the essential sequences and/or regions for capsid protein (CP) subunit recognition within SL1(+) RNA, we used electrophoretic mobility shift assays (EMSA), UV cross-linking, and yeast three-hybrid analyses. The EMSA and UV cross-linking analyses with PVX CP subunits and RNA transcripts corresponding to the SL1(+) RNA showed that the SL1(+) RNA formed complexes with CP subunits. We also conducted EMSA and yeast three-hybrid analyses with RNAs containing various mutations of SL1(+) RNA elements. These analyses indicated that SL1(+) RNA is required for the interaction with PVX CP and that the RNA sequences located at the loop C and tetra loop of the SL1(+) are crucial for CP binding. These results indicate that, in addition to being important for RNA accumulation, the SL1(+) RNA from the 5' region of the PVX genome is also required for specific binding of PVX CP.