• The Plant Pathology Journal
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• 제15권5호
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• pp.295-301
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• 1999

Many of plant defense responses are consequence of transcriptional activation of related genes. We have developed a modified differential screening procedure to isolate tobacco genes that are involved in the defense responses against TMV infection. A cDNA library was constructed from Nicotiana glutinosa leaves infected by TMV under temperature shift conditions. Each of plasmid DNA in the library was hybridized on a set of slot blots to a pool of cDNA probes prepared from either TMV-infected or mock-treated tobacco leaves. Among 900 plasmid DNAs, 81 clones exhibiting significantly enhanced or reduced level of hybridization to either probe were selected for nucleotide sequencing. The clones were listed into 61 genes considering redundancy between the sequences. The genes were identified to be defense-related genes including PR-genes and genes involved in primary or secondary metabolisms. This results supports the implication that plant defense process entails a major shift in total cellular metabolisms rather than activation of a limited number of defense-related genes. Expression patterns of a number of defense-related genes. Expression patterns of a number of selected genes were examined in northern blot analyses. It is notable that the clone 630 of unknown function exhibits expression pattern similar to those of previously known PR-genes. Experiments to elucidate the roles in defense mechanism of a couple of genes newly identified in this study are in progress.

• 한국자원식물학회지
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• 제29권6호
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• pp.658-669
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• 2016

Rice blast, caused by a fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. Analyzing the valuable genetic resources is important in making progress towards blast resistance. Molecular screening of major rice blast resistance (R) genes was determined in 2,509 accessions of rice germplasm from different geographic regions of Asia and Europe using PCR based markers which showed linkage to twelve major blast R genes, Pik-p, Pi39, Pit, Pik-m, Pi-d(t)2, Pii, Pib, Pik, Pita, Pita/Pita-2, Pi5, and Piz-t. Out of 2,509 accessions, only two accessions had maximum nine blast resistance genes followed by eighteen accessions each with eight R genes. The polygenic combination of three genes was possessed by maximum number of accessions (824), while among others 48 accessions possessed seven genes, 119 accessions had six genes, 267 accessions had five genes, 487 accessions had four genes, 646 accessions had two genes, and 98 accessions had single R gene. The Pik-p gene appeared to be omnipresent and was detected in all germplasm. Furthermore, principal component analysis (PCA) indicated that Pita, Pita/Pita-2, Pi-d(t)2, Pib and Pit were the major genes responsible for resistance in the germplasm. The present investigation revealed that a set of 68 elite germplasm accessions would have a competitive edge over the current resistance donors being utilized in the breeding programs. Overall, these results might be useful to identify and incorporate the resistance genes from germplasm into elite cultivars through marker assisted selection in rice breeding.

• Journal of Plant Biotechnology
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• 제45권1호
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• pp.45-54
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• 2018

This research was conducted to study the gene expression of coffee (Coffea arabica L.) seedlings under salt stress condition. A solution of five percent ($2.3dS\;m^{-1}$) deep sea water was used for the salt treatment, and it was thereby compared to normal irrigation water ($0.2dS\;m^{-1}$) used for the control treatment. The mRNA was extracted from the leaves of the coffee seedlings for a comprehensive analysis. In this study, a total of 19,581 genes were identified and aligned to the reference sequences available in the coffee genome database. The gene ontology analysis was performed to estimate the number of genes associated with the identified biological processes, cellular components and molecular functions. Among the 19,581 genes, 7369 (37.64%) were associated with biological processes, 5909 (30.18%) with cellular components, and 5325 (27.19%) with molecular functions. The remaining 978 (4.99%) genes were therefore grouped as unclassified. A differential gene expression analysis was performed using the DESeq2 package to identify the genes that were differentially expressed between the treatments based on fold changes and p-values. Namely, a total of 611 differentially expressed genes were identified (treatment/control) in that case. Among these, 336 genes were up-regulated while 275 of the genes were down-regulated. Of the differentially expressed genes, 60 genes showed statistically significant (p < 0.05) expression, 44 of which were up-regulated and 16 which were down-regulated. We also identified 11 differentially expressed transcription factor genes, 6 of which were up-regulated and rest 5 genes were down-regulated. The data generated from this study will help in the continued interest and understanding of the responses of coffee seedlings genes associated with salinity stress, in particular. This study will also provide important resources for further functional genomics studies.

• 대한미생물학회지
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• 제35권4호
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• pp.299-308
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• 2000

Recently developed cDNA microarray or DNA chip technology allows expression monitoring of expression of hundreds and thousands of genes simultaneously and provides a format for identifying genes as well as changes in their activity. In order to search for changes in gene expression after X irradiation in HL60 cells, cDNA microarray technique was done. In this study, expression of 588 human genes (including oncogenes, tumor suppressor genes, cell cycle regulator genes, intracellular signal transduction modulator genes, apoptosis related genes, transcription factor genes, growth factors and receptor genes, cytokine genes, etc) were analyzed. For cDNA microarray analysis mRNAs were extracted from control and 8 Gy-irradiated HL60 cells. As a result the changes in expression of several genes were observed. This alteration of gene expression was confirmed by reverse transcription-polymerase chain reaction. The expression of heat shock 60 KD protein, c-jun, erythroid differentiation factor, CPP32, myeloid cell nuclear differentiation antigen, MAP kinase-activated protein kinase, interleukin-8, monocyte chemotactic peptide 1 and RANTES genes was increased, but the expression of p55CDC gene was decreased after X irradiation.

• Entomological Research
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• 제48권5호
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• pp.390-399
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• 2018

In order to precisely assess gene expression levels, the suitable internal reference genes must be served to quantify real-time reverse transcription polymerase chain reaction (RT-qPCR) data. For armyworm, Mythimna separata, which reference genes are suitable for assessing the level of transcriptional expression of target genes have yet to be explored. In this study, eight common reference genes, including ${\beta}$-actin (${\beta}$-ACT), 18 s ribosomal (18S), 28S ribosomal (28S), glyceraldehyde-3-phosphate (GAPDH), elongation fator-alpha ($EF1{\alpha}$), TATA box binding protein (TBP), ribosomal protein L7 (RPL7), and alpha-tubulin (${\alpha}$-TUB) that in different developmental stages, tissues and insecticide treatments of M. separata were evaluated. To further explore whether these genes were suitable to serve as endogenous controls, three software-based approaches (geNorm, BestKeeper, and NormFinder), the delta Ct method, and one web-based comprehensive tool (RefFinder) were employed to analyze and rank the tested genes. The optimal number of reference genes was determined using the geNorm program, and the suitability of particular reference genes was empirically validated according to normalized HSP70, and MsepCYP321A10 gene expression data. We found that the most suitable reference genes for the different experimental conditions. For developmental stages, 28S/RPL7 were the optimal reference genes, both $RPL7/EF1{\alpha}$ were suitable for experiments of different tissues, whereas for insecticide treatments, $28S/{\alpha}-TUB$ were suitable for normalizations of expression data. In addition, $28S/{\alpha}-TUB$ were the suitable reference genes because they have the most stable expression among different developmental stages, tissues and insecticide treatments. Our work is the first report on reference gene selection in M. separata, and might serve as a precedent for future gene expression studies.

• The Plant Pathology Journal
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• 제15권1호
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• pp.8-13
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• 1999

Hypersensitive cell death of plants during incompatible plant-pathogen interactions is one of the efficient defense mechanisms of plants against pathogen infections. For better understanding of the molecular mechanisms involved in the plant hypersensitive response (HR), TMV-induced biotic plant cell death and CuSO4-induced abiotic plant cell death were compared in terms of expression patterns of ten different defense-related genes as molecular markers. The genes include five pathogenesis-related protein genes, two plant secondary metabolite-associated genes, two oxidative stress-related genes and one wound-inducible gene isolated from tobacco. Northern blot analyses revealed that a same set of defense-related genes was induced during both biotic and abiotic cell death but with different time and magnitude. The expression of defense-related genes in tobacco plants was temporarily coincided with the time of cell death. However, when suspension cell cultures was used to monitor the expression of defense-related genes, different patterns of the gene expression were detected. This result implies that three are common and, in addition, also different branches of signaling pathways leading to the induced expression of defense-related genes in tobacco during the pathogen- and heavy metal-induced cell death.

• The Plant Pathology Journal
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• 제27권4호
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• pp.301-309
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• 2011

The filamentous fungus Fusarium graminearum is an important cereal pathogen. Although quantitative realtime PCR (qRT-PCR) is commonly used to analyze the expression of important fungal genes, no detailed validation of reference genes for the normalization of qRT-PCR data has been performed in this fungus. Here, we evaluated 15 candidate genes as references, including those previously described as housekeeping genes and those selected from the whole transcriptome sequencing data. By a combination of three statistical algorithms (BestKeeper, geNorm, and NormFinder), the variation in the expression of these genes was assessed under different culture conditions that favored mycelial growth, sexual development, and trichothecene mycotoxin production. When favoring mycelial growth, GzFLO and GzUBH expression were most stable in complete medium. Both EF1A and GzRPS16 expression were relatively stable under all conditions on carrot agar, including mycelial growth and the subsequent perithecial induction stage. These two genes were also most stable during trichothecene production. For the combined data set, GzUBH and EF1A were selected as the most stable. Thus, these genes are suitable reference genes for accurate normalization of qRT-PCR data for gene expression analyses of F. graminearum and other related fungi.

• 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.

• The Plant Pathology Journal
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• 제27권3호
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• pp.272-279
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• 2011

Root colonization of Arabidopsis thaliana with Pseudomonas chlororaphis O6 induces systemic tolerance against diverse pathogens, as well as drought and salt stresses. In this study, we demonstrated that 11 genes in the leaves were up-regulated, and 5 genes were down-regulated as the result of three- to five-days root colonization by P. chlororaphis O6. The identified priming genes were involved in cell signaling, transcription, protein synthesis, and degradation. In addition, expression of selected priming genes were induced in P. chlororaphis O6-colonized plants subjected to water withholding. Genes encoding defense proteins in signaling pathways regulated by jasmonic acid and ethylene, such as VSP1 and PDF1.2, were additional genes with enhanced expression in the P. chlororaphis O6-colonized plants. This study indicated that the expression of priming genes, as well as genes involved in jasmonic acid- and ethylene-regulated genes may play an important role in the systemic induction of both abiotic and biotic stress due to root colonization by P. chlororaphis O6.

• Animal cells and systems
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• 제13권2호
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• pp.235-245
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• 2009

Embryonic stem (ES) cells have a capability to generate all types of cells. However, the mechanism by which ES cells differentiate into specific cell is still unclear. Using microarray technology, the differentiation process in mouse embryonic stem cells was characterized by temporal gene expression changes of mouse ES cells during differentiation in a monolayer culture. A large number of genes were differentially regulated from 1 day to 14 days, and less number of genes were differentially expressed from 14 days to 28 days. The number of up-regulated genes was linearly increased throughout the 28 days of in vitro differentiation, while the number of down-regulated genes reached the plateau from 14 days to 28 days. Most differentially expressed genes were functionally classified into transcriptional regulation, development, extra cellular matrix (ECM),cytoskeleton organization, cytokines, receptors, RNA processing, DNA replication, chromatin assembly, proliferation and apoptosis related genes. While genes encoding ECM proteins were up-regulated, most of the genes related to proliferation, chromatin assembly, DNA replication, RNA processing, and cytoskeleton organization were down-regulated at 14 days. Genes known to be associated with embryo development or transcriptional regulation were differentially expressed mostly after 14 days of differentiation. These results indicate that the altered expression of ECM genes constitute an early event during the spontaneous differentiation, followed by the inhibition of proliferation and lineage specification. Our study might identify useful time-points for applying selective treatments for directed differentiation of mouse ES cells.