• The Plant Pathology Journal
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• v.36 no.1
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• pp.87-97
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• 2020

The development of reverse transcription-polymerase chain reaction using degenerate primers against conserved regions of most potyviral genomes enabled sampling of the potyvirome. However, these assays usually involve sampling potential host plants, but identifying infected plants when they are asymptomatic is challenging, and many plants, especially wild ones, contain inhibitors to DNA amplification. We used an alternative approach which utilized aphid vectors and indicator plants to identify potyviruses capable of infecting common bean (Phaseolus vulgaris). Aphids were collected from a range of asymptomatic leguminous weeds and trees in Iran, and transferred to bean seedlings under controlled conditions. Bean plants were tested serologically for potyvirus infections four-weeks postinoculation. The serological assay and symptomatology together indicated the presence of one potyvirus, and symptomology alone implied the presence of an unidentified virus. The partial genome of the potyvirus, encompassing the complete coat protein gene, was amplified using generic potyvirus primers. Sequence analysis of the amplicon confirmed the presence of an isolate of Wisteria vein mosaic virus (WVMV), a virus species not previously identified from Western Asia. Phylogenetic analyses of available WVMV sequences categorized them into five groups: East Asian-1 to 3, North American and World. The Iranian isolate clustered with those in the World group. Multiple sequence alignment indicated the presence of some genogroup-specific amino acid substitutions among the isolates studied. Chinese isolates were sister groups of other isolates and showed higher nucleotide distances as compared with the others, suggesting a possible Eastern-Asian origin of WVMV, the main region where Wisteria might have originated.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.306-312
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• 2010

The pathotypes of Cercospora beticola, causal agent of sugar beet leaf spot disease, were identified by application of pathogenicity test using 100 isolates obtained from the provinces with intensive sugar beet cultivation. For the identification of pathotypes, five sugar beet cultivars were used each with different resistance factors. Cultivar reactions were determined by inoculation of cultivars with the isolates under controlled conditions and measuring disease severity on the $15^{th}$ day according to the 1-9 KWS Scale. Based on the reactions of the five cultivars, a total of 15 pathotypes were detected. All employed sugar beet cultivars were resistant to Pathotype no:1 comprising most of the isolates. Genetic diversity of the causal agent was characterized by AFLP reaction. The products acquired at the end of AFLP reaction were detected by means of Beckman CEQ 8800 DNA Capillary Series Analysis and the results obtained were evaluated according to the similarity index UPGMA. For the genetic analysis of C. beticola isolates, 9874 polymorphic fragments of sizes between 100 and 500 bp were analysed which were generated by nine primers. The dendrogram derived from AFLP analysis depicted the existence of five different subgroups. The polymorphism rate among isolates was 91.13% and the dendrogram distribution of the pathotypes obtained by pathogenicity indicated that pathotypes were not discriminated and did not compose any groups.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.459-466
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• 2018

In January 2017, discolored black oat seeds were found in the storage depot of a farmhouse in Jeongeup. Pyrenophora sp. was detected in 45% of the oat seeds surveyed. All Pyrenophora isolates obtained from the seeds were identified as Pyrenophora avenae based on the sequences of internal transcribed spacer (ITS) rDNA regions and glyceraldehyde 3-phosphate dehydrogenase (GPDH) gene and validated by morphological and cultural characterization. A phylogenetic tree constructed using the ITS and GPDH sequences showed that the Korean isolates of P. avenae comprise of four genetically distinct groups. Pathogenicity test validated that the fungus is an infectious agent responsible for discolored black seeds and leaf blotch in oat plants. This is the first study report that P. avenae causes leaf blotch disease of oat in Korea.

• Research in Plant Disease
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• v.28 no.4
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• pp.209-220
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• 2022

Charcoal canker of oak, which has recently increased in southern Iran, could pose a serious threat to the entire forest ecosystem in the near future. In addition, it seems that climate change and its consequences, such as drought in the southern regions of Iran, have exacerbated this phenomenon. Consequently, the objective of this study was to identify the fungal pathogens that could cause charcoal canker disease in the oak forests of South Zagros. It was also sought to find associations between changes in the occurrence/exacerbation of charcoal canker disease under non and intense drought stress in non-inoculated or inoculated Quercus brantii seedlings. In total, 120 isolates were obtained from eight oak forests located in the Zagros Mountains of Southern Iran, Kohgiluyeh & Boyer-Ahmad and Fars provinces, which were classified as Biscogniauxia mediterranea based on morphological assessment. Subsequently, molecular assay confirmed the result by phylogenetic inference of internal transcribed spacer-rDNA regions, α-actin, and β-tubulin genes. The results of the pathogenicity test showed that the response of isolates of B. mediterranea (Iran-G1 and Iran-M70) was varied in different environments for the measured necrotic lesion length. In comparison with the control moisture treatments (non-stress), the necrotic lesion length in inoculated treatments increased under intense drought stress. In general, inoculated oak seedlings' exposure to water-deficient stress by the pathogen of B. mediterranea could affect the spread/severity of the charcoal canker disease.

• Animal cells and systems
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• v.16 no.1
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• pp.11-19
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• 2012

A major concern regarding the collection and storage of biodiversity information is the inefficiency of conventional taxonomic approaches in dealing with a large number of species. This inefficiency has increased the demand for automated, rapid, and reliable molecular identification systems and large-scale biological databases. DNA-based taxonomic approaches are now arguably a necessity in biodiversity studies. In particular, DNA barcoding using short DNA sequences provides an effective molecular tool for species identification. We constructed a large-scale database system that holds a collection of 5531 barcode sequences from 2429 Korean species. The Korea Barcode of Life database (KBOL, http://koreabarcode.org) is a web-based database system that is used for compiling a high volume of DNA barcode data and identifying unknown biological specimens. With the KBOL system, users can not only link DNA barcodes and biological information but can also undertake conservation activities, including environmental management, monitoring, and detecting significant organisms.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.78-83
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• 2005

Recently, much attention has been focused on plant antioxidants, because they are expected to protect against oxidative damage, possibly preserving biological functions of cells. Antioxidant compounds were isolated from Angelica keiskei through extraction with 80% EtOH, and fractionations were carried out sequentially with n-hexane, chloroform, ethyl acetate, n-butanol, and water. Two active compounds were isolated from ethyl acetate fraction by silica gel column chromatography, and were identified as isoquercitrin ($quercetin-3-O-{\beta}-D-glucose$) and hyperoside ($quercetin-3-O-{\beta}-D-glucose$). Isoquercitrin and hyperoside showed strong antioxidative potency, as revealed by evaluation of their ABTS, DPPH, OH, and $H_{2}O_{2}$ radical-scavenging activities, and ex vivo DNA damage-protecting effects.

• Radiation Oncology Journal
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• v.33 no.3
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• pp.256-260
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• 2015

Purpose: Mefenamic acid (MEF) as a non-steroidal anti-inflammatory drug is used as a medication for relieving of pain and inflammation. Radiation-induced inflammation process is involved in DNA damage and cell death. In this study, the radioprotective effect of MEF was investigated against genotoxicity induced by ionizing radiation in human blood lymphocytes. Materials and Methods: Peripheral blood samples were collected from human volunteers and incubated with MEF at different concentrations (5, 10, 50, or $100{\mu}M$) for two hours. The whole blood was exposed to ionizing radiation at a dose 1.5 Gy. Lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis blocked binucleated lymphocyte. Results: A significant decreasing in the frequency of micronuclei was observed in human lymphocytes irradiated with MEF as compared to irradiated lymphocytes without MEF. The maximum decreasing in frequency of micronuclei was observed at $100{\mu}M$ of MEF (38% decrease), providing maximal protection against ionizing radiation. Conclusion: The radioprotective effect of MEF is probably related to anti-inflammatory property of MEF on human lymphocytes.

• Journal of Microbiology
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• v.42 no.3
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• pp.194-199
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• 2004

Investigation of the expression of the riboflavin (rib) genes, which are found immediately downstream of luxG in the lux operon in Photobacterium phosphoreum, provides more information relevant to the evolution of bioluminescence, as well as to the regulation of supply of flavin substrate for bacterial bioluminescence reactions. In order to answer the question of whether or not the transcriptions of lux and rib genes are integrated, a transcriptional termination assay was performed with P. phoxphoreum DNA, containing the possible stem-loop structures, located in the intergenic region of luxF and luxE ($\Omega$$\_$A/), of luxG and ribE ($\Omega$$\_$B/), and downstream of ribA ($\Omega$$\_$c/). The expression of the CAT (Chloram-phenicol Acetyl Transferase) reporter gene was remarkably decreased upon the insertion of the stem-loop structure ($\Omega$$\_$c/) into the strong lux promoter and the reporter gene. However, the insertion of the structure ($\Omega$$\_$B/) into the intergenic region of the lux and the rib genes caused no significant change in expression from the CAT gene. In addition, the single stranded DNA in the same region was protected by the P. phosphoreum mRNA from the Sl nuclease protection assay. These results suggest that lux genes and rib genes are part of the same operon in P. phosphoreum.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.8-13
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• 1992

Low doses of ionizing radiation from external or internal sources cause heterogeneous distribution of energy deposition events in the exposed biological system. With the cell being the individual element of the tissue system, the fraction of cells hit, the dose received by the hit, and the biological response of the cell to the dose received eventually determine the effect in tissue. The hit cell may experience detriment, such as change in its DNA leading to a malignant transformation, or it may derive benefit in terms of an adaptive response such as a temporary improvement of DNA repair or temporary prevention of effects from intracellular radicals through enhanced radical detoxification. These responses are protective also to toxic substances that are generated during normal metabolism. Within a multicellular system, the probability of detriment must be weighed against the probability of benefit through adaptive responses with protection against various toxic agents including those produced by normal metabolism. Because irradiation can principally induce both, detriment and adaptive responses, one type of affected cells may not be simply summed up at the expense of cells with other types of effects, in assessing risk to tissue. An inventory of various types of effects in the blood forming system of mammals, even with large ranges of uncertainty, uncovers the possibility of benefit to the system from exposure to low doses of low LET radiation. This experimental approach may complement epidemiological data on individuals exposed to low doses of ionizing radiation and may lead to a more rational appraisal of risk.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.2
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• pp.163-169
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• 2018

This study examined the expression of heat shock protein 70 (Hsp70) in red seabream Pagrus major infected by the, acanthocephalan parasites Longicollum pagrosomi. We cloned the full-length Hsp70 cDNA from the liver of the red seabream. The full-length cDNA had a 1,950 bp open reading frame (ORF) that encoded a protein of 650 amino acids. The deduced amino acid sequence of Hsp70 contained all of the conserved Hsp70 family signature sequences and an adenosine triphosphate (ATP)/guanosine triphosphate (GTP) binding motif, including the EEVD (consensus sequence that terminates in Hsp70 family) consensus sequence. The expression of Hsp70 mRNA was upregulated int the fish head-kidney and liver, as determined by quantitative real-time PCR. We quantified the Hsp70 mRNA expression in normal red seabream and fish infected fish by L. pagrosomi. The expression of Hsp70 mRNA was significantly higher in the infected red seabream. These results suggest that Hsp70 play a role of protection against stress and inflammation caused by the parasite and may help maintain homeostasis.