검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 22

        1.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The Hippo pathway was originally discovered in Drosophila by genetic screening and it has been shown to be conserved in various organisms including human. Until now, the essential roles of Hippo pathway in regulating cell proliferation, apoptosis, tumorigenesis, and organ size control is extensively studied. Currently, Mats1/2 (Mob1a/1b), one of the important components in Hippo pathway, mutant mice were generated which has abnormal phenotype such as resistance to apoptosis and spontaneous tumorigenesis. Of note, Mats1/2 mutant mice also showed dental malocclusion. Therefore, in this study, we have evaluated the bone phenotype of Mats1/2 mutant mice. Although the mRNA expressions of Mats1 or Mats2 were observed in both osteoclastogenesis and osteoblastogenesis, the increase of Mats1 level was most prominent during osteoblastogenesis. The RANKL-induced osteoclast differentiation from bone marrow-derived macrophages (BMMs) was unaltered upon Mats1/2 mutation; however, the osteoblast differentiation using calvarial pre-osteoblasts was significantly reduced in Mats1/2 mutant mice compare to that of wild type mice. In accordance with in vitro results, Mats1/2 mutant mice showed decreased bone volume as well as increased trabecular separation in μCT analyses. These results may provide novel prospect of the probable linkage between Hippo pathway and bone homeostasis.
        4,000원
        3.
        2015.04 구독 인증기관·개인회원 무료
        The melon and cotton aphid Aphis gossypii Glover (Hemiptera; Aphididae) is one of the most serious pests worldwide. We surveyed insecticide susceptibility in A. gossypii field populations to 12 insecticides to examine resistance ratios. The levels of insecticide resistance were extremely high, especially to neonicotinoids. One point mutation was found in the beta1 subunit loop D region of the nicotinic acetylcholine receptor (nAChR) of the imidacloprid-resistant strain. Feeding behavior analysis using an electrical penetration graph showed that sublethal doses of imidacloprid had significant effects on the duration of phloem ingestion. In addition, higher doses of imidacloprid induced contact toxicity rather than inhibition of feeding behavior. Temperature and insecticide are two important factors that affect survival, reproduction and other physiological processes of insects. To determine interactions of temperature and insecticide treatment on susceptible and imidacloprid-resistant strains of A. gossypii, adults were exposed to three temperatures (17, 22, and 28℃) or combinations of three temperatures and imidacloprid (LC20), and the expression of several genes (heat shock protein 70, cuticle protein, cytochrome P450, and elongation factor) were analyzed. Additionally, the effect of electron beam irradiation on development, reproduction, and several gene expression of imidacloprid-resistant and -susceptible A. gossypii were compared.
        4.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Bovine coat color is decided by the melanocortin receptor 1 (MC1R) genotype mutation and melanogenesis. Specially, in the various cattle breeds, dominant black coat color is expressed by dominant genotype of ED, red or brown is expressed in the frame shift mutation of recessive homozygous e by base pair deletion and wild type of E+ is expressed in various coat colors. However, not very well known about the effected of MC1R genotype mutation on the coat color through family lines in KBC. Therefore, this study were to investigate effect of MC1R genotype mutation on the coat color, and to suggest mating breed system in accordance with of MC1R genotype for increased on brindle coat color appearance. Parents (sire 2 heads and dam 3 heads) and offspring (total : 54 heads) from crossbreeding in KBC family line with the MC1R genotype and phenotype records were selected as experimental animals. The relationship between melanocortin 1 receptor (MC1R) genotypes expression verified by PCR-RFLP, and brindle coat color appearance to the family line of the cross mating breed from MC1R genotype pattern was determined. As a result, 4MC1R genetic variations, E+/E+ (sire 1), E+/e (sire 2 and dam 3), E+/e with 4 bands of 174, 207 and 328 bp (dam 1) and E+/e with 3 bands of 174, 207, 328 and 535 bp (dam 2) from parents (sire and dam) of KBC. However, 3 genetic variations, e/e (24%), E+/E+ (22%) and E+/e (56%) were identified in offspring. Also, brindle coat color expressrated was the e/e with the 0%, E+/E+ with 67% and E+/e with 77% from MC1R genotype in offspring on the cross mating of KBC. Furthermore, when the sire had E+/e genotype and the dam had E+/E+ with the 3 bands or E+/e genotype, and both had whole body-brindle coat color, 62% of the offspring had whole body-brindle coat color. Therefore, the seresults, the mating system from MC1R genotype patterns of the sires (E+/e) and dams (E+/E+ with the 3 bands or E+/e) with brindle coat color may have the highest whole body-brindle coat color expression in their offspring.
        4,000원
        5.
        2012.06 구독 인증기관 무료, 개인회원 유료
        Although neutrophils function in both defense and tissue destruction, their defensive roles have rarely been studied in association with periodontitis. We hypothesized that periph¬eral neutrophils are pre-activated in vivo in periodontitis and that hyperactive neutrophils would show enhanced phago-cytic ability as well as an increased production of reactive oxygen species (ROS). Peripheral blood neutrophils from patients with aggressive periodontitis and age/gender¬matched healthy subjects (10 pairs) were isolated. The levels of CD11b and CD64 expression on the neutrophils and the level of plasma endotoxin were determined by flow cytometry and a limulus amebocyte lysate test, respectively. In addition, neutrophils were subjected to a flow cytometric phagocytosis assay and luminol-enhanced chemilumines¬cence for non-opsonized Fusobacterium nucleatum in parallel. The neutrophilsfrom most patients expressed increased levels of both CD11b and CD64. In addition, the plasma from these patients tended to contain a higher level of endotoxin than the healthy controls. In contrast, no differences were found between the two groups with regard to phagocytosis or ROS generation by F. nucleatum. The ability to phagocytose F. nucleatum was found to positively correlate with the ability to produce ROS. In conclusion, peripheral neutrophils from patients with aggressive periodontitis are hyperactive but not hyperreactive to F. nucleatum.
        4,000원
        6.
        2010.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        One hundred one enterococcal isolates from feces of livestock animals in Korea were screened for the presence of bacteriocins. Sixteen of 41 (39%) E. faecalis and 4 of 56 (7.1%) E. faecium isolates showed antimicrobial activity against at least one indicator strain. Only 4 of 20 the enterococcal isolates showing antimicrobial activity possessed at least one bacteriocin gene. While entA and entB were detected in three isolates as a pair of genotype, entQ, bac31, and AS-48 were not found in the enterococcal isolates. In almost all isolates, a correlation between genotype and phenotype of these determinants was not always observed.
        4,000원
        7.
        2009.12 구독 인증기관 무료, 개인회원 유료
        Human mesenchymal stem cell (hMSCs) isolated from human adult bone marrow have self-renewal capacity and can differentiate into multiple cell types in vitro and in vivo. A number of studies have now demonstrated that MSCs can differentiate into various neuronal populations. Due to their autologous characteristics, replacement therapy using MSCs is considered to be safe and does not involve immunological complications. The basic helix-loop-helix (bHLH) transcription factor Olig2 is necessary for the specification of both oligodendrocytes and motor neurons during vertebrate embryogenesis. To develop an efficient method for inducing neuronal differentiation from MSCs, we attempted to optimize the culture conditions and combination with Olig2 gene overexpression. We observed neuron-like morphological changes in the hMSCs under these induction conditions and examined neuronal marker expression in these cells by RTPCR and immunocytochemistry. Our data demonstrate that the combination of Olig2 overexpression and neuron-specific conditioned medium facilitates the neuronal differentiation of hMSCs in vitro. These results will advance the development of an efficient stem cell-mediated cell therapy for human neurodegenerative diseases.
        4,000원
        8.
        2009.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Epigallocatechin-3-gallate (EGCG) and theaflavins (TF) are polyphenols included in green and black teas, respectively. Both green and black teas have been studied for their potential health benefits for cancer. Hypoxia-inducible factor (HIF) has been implicated multiple physiological and pathophysiological pathways, particularly, oncogenesis. But, the molecular pathways that govern the cell response to EGCG are not fully elucidated. The present study investigated the intracellular mechanism in oral squamous cell carcinoma (OSCC) cells treated with EGCG, focusing on HIF-1 expression and its effect on epithelial phenotype. EGCG decreased phosphorylated Raf-1 protein in YD 8 OSCC cell, but B-raf protein was not affected at all by EGCG and TF. In addition, we here found that EGCG regulated HIF-1α expression independent of Raf-1 protein. Taken together with our previous result, the result imply that EGCG is attributed to the HIF-1α expression via Raf/MEK/ERK pathway, and the HIF-1α expression is associated with the change of epithelial phenotype in OSCC cell.
        4,000원
        13.
        2015.07 서비스 종료(열람 제한)
        The wild relatives of soybean [Glycine soja Sieb. and Zucc.] have curly/wavy nature whereas cultivated varieties are upright. Such morphological characteristics have agronomic importance too. To investigate the molecular mechanism of development contributing to coiled morphology, screening was carried out to look for Arabidopsis mutants in activation tagging lines obtained by activation T-DNA treatment that have curly/wavy morphology. A mutant named Coiled Branch 1 (cbr1), is found to have a wavy and curly morphology with coiling branches. Plasmid rescue and genomic southern blot analysis revealed the site of T-DNA insertion in the genome. RT-PCR was performed to monitor expression levels of the genes adjacent to the T-DNA integration sites, and showed the activation of an E3 ubiquitin ligase gene. Database search showed that the gene with the RING domain belongs to a family of E3 ubiquitin ligases. Complementation test by overexpression and RNA interference of the gene was also carried out. The complementation test results showed that the novel gene activation tagging affected the cbr1 mutant phenotypes. Ubiquitylation has been linked virtually to every cellular process including plant development. E3 ubiquitin ligase has been reported to recognize target proteins that are to be ubiquinated for further degradation by the proteasome complex. Further, more detailed studies are needed to identify the specific substrate(s) of the novel E3 ubiquitin ligase gene.
        14.
        2015.07 서비스 종료(열람 제한)
        Map-based cloning is a basic method for identifying the mutated gene in plants. We selected the gametophytic mutant, named as AP-26-09, in activation-tagging pool. Mutant plant showed various kinds of pollen phenotype, such as the different number of nucleus or abnormal shapes. For the map-based gene cloning, we conducted phenotypic analysis of F2 mapping population through the screening of DAPI-stained pollen using fluorescence microscopy. Genomic DNA of F2 plants is prepared from leaves of approximately 1000 plants. In order to define chromosomal region where mutation is located, we designed SSLP markers and performed PCR amplification. In this study, we characterized gametophytic mutant and determined the chromosomal location using map-based approach.
        15.
        2015.07 서비스 종료(열람 제한)
        The world population is projected to reach to 9.6 billion people by 2050. With increasing population and improving living standards, the demand for food is accelerating. In order to meet increasing demand for food while the arable land and other resources are decreasing, agriculture needs all the tools available to sustainably increase crop yields. Development of effective GM traits to protect crops from abiotic and biotic stressors is a critical aspect of sustainable yield improvement. Efficient identification of traits and rapid integration of the traits into commercial elite germplasm requires robust and rapid traits testing. Monsanto have developed numerous high-throughput phenotyping platforms to support rapid trait identification and integration. Selected phenotyping platforms will be reviewed to gain understanding on how they are utilized for trait phenotyping.
        16.
        2014.09 서비스 종료(열람 제한)
        We previously reported that DNA hypermethylation of SRY promoter is associated with emergence of male-to-female sex reversal. The normality of offspring is achieved by relatively complete and correct nuclear reprogramming during somatic cell nuclear transfer and cloning process. The purpose of this study is to determine whether DNA demethylation of SRY promoter induced by 5-aza-2'-deoxycytidine (AzC) DNA methylation inhibitor may get back phenotypic XY sex reversal female to normal male in SCNT cloning. Canine femoral skin fibroblast cells were established from SCNT-cloned XY sex reversed female (GSF335). Using bisulfite genomic sequencing analysis, DNA methylation levels of SRY promoter in non-treated (normal) and 1uM AzC-treated cells were 88.4% and 55.3% in treatment for 4 days respectively. Seven SCNT-cloned puppies were cloned using the AzC-treated cells as donor cell. Six of those clones showed phenotypically normal male, through one puppy (GSF451) was only observed into male-to-female sex reversal with female genitalia. In umbilical cord tissue, DNA methylation levels on SRY promoter of GSF451 clone and the other clones were 79.2% and 5.7% to 62.2% respectively, which was approximately similar to those of non-treated (normal) and AzC-treated cells. Also, cloned puppies originated from AzC-treated cells implied significantly multiple body weight and height compared to age-matched SCNT-cloned control, which may be underlying in size-effect of AzC-treatment. Our findings suggest that DNA demethylated status of SRY promoter induced by AzC is likely to facilitate normal development including sex differentiation through epigenetic alteration of donor cells.
        17.
        2013.07 서비스 종료(열람 제한)
        Understanding salt tolerance mechanisms is important for the increase of crop yields, and so, several screening approaches were developed to identify plant genes which are involved in salt tolerance of plants. Here, we transformed the Arabidopsis cDNA library into a salt-sensitive calcineurin (CaN)-deficient (cnbD) yeast mutant and isolated the colonies which can suppress salt-sensitive phenotype of cnbD mutant. Through this functional complementation screen, a total of 34 colonies functionally suppressed the salt-sensitive phenotype of cnbD yeast cells, and sequencing analysis revealed that these are 9 genes, including CaS, AtSUMO1 and AtHB-12. Among these genes, the ectopic expression of CaS gene increased salt tolerance in yeast, and CaS transcript was up-regulated under high salinity conditions. CaS-antisense transgenic plants showed reduced root elongation under 100 mM NaCl treatment compared to the wild type plant, which survived under 150 mM NaCl treatment, whereas CaS-antisense transgenic plant leaves turned yellow under 150 mM NaCl treatment. These results indicate that the expression of CaS gene is important for stress tolerance in yeast and plants.
        18.
        2012.07 서비스 종료(열람 제한)
        In plant, senescence is associated with various aspects of the final stage of leaf development, nutrient relocation from leaves to reproducing seeds and stress resistance, and yield which is the most important trait in crops. Thus, the increase of knowledge on the regulatory processes of plant senescence will allow us to manipulate senescence for agronomic benefit in the future. of genetic studies have been conducted with mutants, where most of studies were focused on the delayed senescence mutants which are associated with positive factors on senescence by treating EMS to Koshikari, we induced a mutant showing early senescence phenotype, which possibly enable us to identify a negative factor of senescence. The appearance of the mutant is identical before booting stage and then the mutant showed senescence phenotype rignt before booting stage whereas Koshikari have health green leaves. The clumn length of the mutant is 98cm and the panicle length is 23cm as same as those of Koshikari. The chlorophyl contents of the mutant leaves, measured by SPAD, decreased during senescence. The soluble protein contents in the mutant leaves also decreased but no differences in the constitution reolved 1D-SDS-PAGE was detected. However, an additional shotgun proteomic approach to detect the differences of the protein constitutions during the senescence in the mutant leaves will be conducted.
        20.
        2009.12 KCI 등재 서비스 종료(열람 제한)
        Sweetpotato is one of the important starch crops, current more considered as an industrial crop rather than food because it has higher starch content (over 80% of biomass), it is used for bio resources for industrial area. In this study, we generated S598A (a mutant gene of oat phytochrome A) sweetpotato plant using Agrobacterium-transformation method. Morphological characteristics of S598A plant were compared with the wild type sweetpotato, S598A had darker green leaves, increased chlorophyll content higher than to two-fold, delayed leaf senescence, shorter plant height (60% shorter than that of the wild type), more number of leaves and petioles about 1.8-fold, shorter petiole length (30% shorter), 1.2-fold more branches and 1.6-fold thicker stem diameters. From this study, S598A plants with such phenotypic characteristics might be able to use the solar energy efficiently, to have increased tolerance to biotic and abiotic stresses and finally to increase productivity (not only starch yield but also root biomass yield). S598A sweetpotato lines are under field trials.
        1 2