• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1503-1509
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• 2014

With the purpose of facilitating the process of stable strain generation, a shuttle vector for integration of genes via a double recombination event into two ectopic sites on the Sulfolobus acidocaldarius chromosome was constructed. The novel chromosomal integration and expression vector pINEX contains a pyrE gene from S. solfataricus P2 ($pyrE_{sso}$) as an auxotrophic selection marker, a multiple cloning site with histidine tag, the internal sequences of malE and malG for homologous recombination, and the entire region of pGEM-T vector, except for the multiple cloning region, for propagation in E. coli. For stable expression of the target gene, an ${\alpha}$-glucosidase-producing strain of S. acidocaldarius was generated employing this vector. The malA gene (saci_1160) encoding an ${\alpha}$-glucosidase from S. acidocaldarius fused with the glutamate dehydrogenase ($gdhA_{saci}$) promoter and leader sequence was ligated to pINEX to generate pINEX_malA. Using the "pop-in" and "pop-out" method, the malA gene was inserted into the genome of MR31 and correct insertion was verified by colony PCR and sequencing. This strain was grown in YT medium without uracil and purified by His-tag affinity chromatography. The ${\alpha}$-glucosidase activity was confirmed by the hydrolysis of $pNP{\alpha}G$. The pINEX vector should be applicable in delineating gene functions in this organism.

• Tuberculosis and Respiratory Diseases
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• v.83 no.3
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• pp.211-217
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• 2020

The gold standard method for diagnosis of tuberculosis is the isolation of Mycobacterium tuberculosis through culture, but there is a probability of cross-contamination in simultaneous cultures of samples causing false-positives. This can result in delayed treatment of the underlying disease and drug side effects. In this paper, we reviewed studies on false-positive cultures of M. tuberculosis. Rate of occurrence, effective factors, and extent of false-positives were analyzed. Ways to identify and reduce the false-positives and management of them are critical for all laboratories. In most cases, false-positive is occurring in cases with only one positive culture but negative direct smear. The three most crucial factors in this regard are inappropriate technician function, contamination of reagents, and aerosol production. Thus, to reduce false-positives, good laboratory practice, as well as use of whole-genome sequencing or genotyping of all positive culture samples with a robust, extra pure method and rapid response, are essential for minimizing the rate of false-positives. Indeed, molecular approaches and epidemiological surveillance can provide a valuable tool besides culture to identify possible false positives.

• BMB Reports
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• v.37 no.2
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• pp.206-212
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• 2004

The genes that are located within the odvp-6e/odv-e56 region of the Choristoneura fumiferana granulovirus (ChfuGV) were identified by sequencing the 11 kb BamHI restriction fragment on the ChfuGV genome. The global GC content that was calculated from the data obtained from this genomic region was 34.96%. The open-reading frames (ORFs), located within the odvp-6e/odv-e56 region, are presented and compared to the equivalent ORFs that are located at the same region in other GVs. This region is composed of 14 ORFs, including three ORFs that are unique to ChfuGV with no obvious homologues in other baculoviruses as well as eleven ORFs with homologues to granuloviral ORFs, such as granulin, CfORF2, pk-1, ie-1, odv-e18, p49, and odvp-6e/odv-e56. In this study, the conceptual products of seven major conserved ORFs (granulin, CfORF2, IE-1, ODV-E18, p49 and ODVP-6E/ODV-E56) were used in order to construct phylogenetic trees. Our results show that granuloviruses can be grouped in 2 distinct groups as follows: Group I; Choristoneura fumiferana granulovirus (ChfuGV), Cydia pomonella granulovirus (CpGV), Phthorimaea operculella granulovirus (PhopGV), and Adoxophyes orana granulovirus (AoGV). Group II; Xestia c-nigrum granulovirus (XcGV), Plutella xylostella granulovirus (PxGV), and Trichoplusia ni granulovirus (TnGV). The ChfuGV conserved proteins are most closely related to those of CpGV, PhopGV, and AoGV. Comparative studies, performed on gene arrangements within this region of genomes, demonstrated that three GVs from group I maintain similar gene arrangements.

• Korean Journal of Plant Resources
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• v.30 no.3
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• pp.323-330
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• 2017

Eleutherococcus senticosus (Siberian ginseng) is an important medicinal tree found in northeast Asia. In this study, we analyzed the genome-wide distribution of microsatellites in E. senticosus. By sequencing 711 clones from an SSR-enriched genomic DNA library, we obtained 12 polymorphic SSR markers, which also revealed successful amplicons in E. senticosus accessions. Using the developed SSR markers, we estimated genetic diversity and population structure among 131 E. senticosus accessions in Korea and China. The number of alleles ranged from 2 to 11, with an average of 7.4 alleles. The mean values of observed heterozygosity ($H_O$) and expected heterozygosity ($H_E$) were 0.59 and 0.56, respectively. The average polymorphism information content (PIC) was 0.51 in all 131 E. senticosus accessions. E. senticosus accessions in Korea and China showed a close genetic similarity. Significantly low pairwise genetic divergence was observed between the two regions, suggesting a relatively narrow level of genetic basis among E. senticosus accessions. Our results not only provide molecular tools for genetic studies in E. senticosus but are also helpful for conservation and E. senticosus breeding programs.

• Genomics & Informatics
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• v.7 no.4
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• pp.195-202
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• 2009

BIRC5 (Survivin) belongs to the inhibitor of apoptosis gene family. The BIRC5 protein inhibits caspases and consequently blocks apoptosis. Thus, BIRC5 contributes to the progression of cancer allowing for continued cell proliferation and survival. In this study, we identified eight sequence variants of BIRC5 through direct DNA sequencing. Among the eight single nucleotide polymorphisms (SNPs), six common variants with frequencies higher than 0.05 were selected for larger-scale genotyping (n=1,066). Results of the study did not show any association between the promoter region polymorphisms and the clearance of hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) occurrence. This is in line with a previous study in which polymorphisms in the promoter region does not influence the function of BIRC5. Initially, we were able to detect a signal with the ＋9194A>G, which disappeared after multiple corrections but led to a change in amino acid. Similarly, we were also able to detect an association signal between two haplotypes (haplotype-2 and haplotype-5) on the onset age of HCC and/or HCC occurrence, but the signals also disappeared after multiple corrections. As a result, we concluded that there was no association between BIRC5 polymorphisms and the clearance HBV infection and/or HCC occurrence. However, our results might useful to future studies.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1398-1403
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• 2016

The simultaneous detection and accurate identification of hepatitis A virus (HAV) is critical in food safety and epidemiological studies to prevent the spread of HAV outbreaks. Towards this goal, a one-step duplex reverse-transcription (RT)-PCR method was developed targeting the VP1/P2B and VP3/VP1 regions of the HAV genome for the qualitative detection of HAV. An HAV RT-qPCR standard curve was produced for the quantification of HAV RNA. The detection limit of the duplex RT-PCR method was 2.8 × 10¹ copies of HAV. The PCR products enabled HAV genotyping analysis through DNA sequencing, which can be applied for epidemiological investigations. The ability of this duplex RT-PCR method to detect HAV was evaluated with HAV-spiked samples of fresh lettuce, frozen strawberries, and oysters. The limit of detection of the one-step duplex RT-PCR for each food model was 9.4 × 10² copies/20 g fresh lettuce, 9.7 × 10³ copies/20 g frozen strawberries, and 4.1 × 10³ copies/1.5 g oysters. Use of a one-step duplex RT-PCR method has advantages such as shorter time, decreased cost, and decreased labor owing to the single amplification reaction instead of four amplifications necessary for nested RT-PCR.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.267-279
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• 2020

Fig mosaic is a viral disease (FMD) that spreads in Palestinian common fig (Ficus carica L.) orchards. Recognizing the economic value of fig plants and the harmful nature of FMD, the disease poses a significant threat to the economy of the fig production in Palestine. We applied the reverse transcription and amplification (RT-PCR) and PCR technique to leaf samples of 77 trees and 14 seedlings of 17 fig cultivars. The samples were collected from orchards in the main fig-growing provinces of the Palestinian West Bank, to assess the prevalence of viruses associated with FMD, and confirm a possible link of symptoms with viruses detected. Four viruses were detected: Fig mosaic virus (FMV), Fig badnavirus-1 (FBV-1), Fig leaf mottle-associated virus 2 (FLMaV-2), and Fig fleck-associated virus (FFkaV). FMV and FBV-1 were found in all tested fig plants (100%), while FLMaV-2 and FFkaV were detected in 61.5% and 33% of the fig samples, respectively. The high incidence of FBV-1 in the newly propagated symptomatic and symptomless seedlings from different cultivars may be an indication that FBV-1 is integrated into the genome of the fig in a cultivar nondiscriminatory manner. Very weak or no association was detected between FMD symptoms severity in the 17 Palestinian fig cultivars with the various viruses' combinations observed (i.e., number of the viruses infecting the plant). These results support the notion that FMD symptom severity expression is likely to be controlled by a combination of FMV infection, cultivars, and environmental factors, rather than the number of viruses infecting the plant.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.194-204
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• 2009

Cytoplasmic male sterility (CMS) and fertility restoration have been utilized as valuable tools for $F_1$-hybrid seed production in many crops despite laborious breeding processes. Molecular markers for the selection of CMS-related genes help reduce the expenses and breeding times. A previously reported genomic region containing the Ppr-B gene, which is responsible for restoration of fertility and corresponds to the Rfo locus, was used to develop gene-based or so-called "functional" markers for allelic selection of the restorer-of-fertility gene (Rfo) in $F_1$-hybrid breeding of radish (Raphanus sativus L.) Polymorphic sequences among Rfo alleles of diverse breeding lines of radish were examined by sequencing the Ppr-B alleles. However, presence of Ppr-B homolog, designated as Ppr-D, interferes on specific PCR amplification of Ppr-B in certain breeding lines. The organization of Ppr-D, resolved by genome walking, revealed extended homology with Ppr-B even in the promoter region. Interestingly, PCR amplification of Ppr-D was repeatedly unsuccessful in certain breeding lines implying the lack of Ppr-D in these radishes. Ppr-B could only be successfully amplified for analysis through designing primers based on the sequences unique to Ppr-B that exclude interference from Ppr-D gene. Four variants of Rfo alleles were identified from 20 breeding lines. A combination of three molecular markers was developed in order to genotype the Rfo locus based on polymorphisms among four different variants. These markers will be useful in facilitating $F_1$-hybrid cultivar development in radish.

• Molecules and Cells
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• v.44 no.10
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• pp.723-735
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• 2021

Spemann organizer is a center of dorsal mesoderm and itself retains the mesoderm character, but it has a stimulatory role for neighboring ectoderm cells in becoming neuroectoderm in gastrula embryos. Goosecoid (Gsc) overexpression in ventral region promotes secondary axis formation including neural tissues, but the role of gsc in neural specification could be indirect. We examined the neural inhibitory and stimulatory roles of gsc in the same cell and neighboring cells contexts. In the animal cap explant system, Gsc overexpression inhibited expression of neural specific genes including foxd4l1.1, zic3, ncam, and neurod. Genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) and promoter analysis of early neural genes of foxd4l1.1 and zic3 were performed to show that the neural inhibitory mode of gsc was direct. Site-directed mutagenesis and serially deleted construct studies of foxd4l1.1 promoter revealed that Gsc directly binds within the foxd4l1.1 promoter to repress its expression. Conjugation assay of animal cap explants was also performed to demonstrate an indirect neural stimulatory role for gsc. The genes for secretory molecules, Chordin and Noggin, were up-regulated in gsc injected cells with the neural fate only achieved in gsc uninjected neighboring cells. These experiments suggested that gsc regulates neuroectoderm formation negatively when expressed in the same cell and positively in neighboring cells via soluble factors. One is a direct suppressive circuit of neural genes in gsc expressing mesoderm cells and the other is an indirect stimulatory circuit for neurogenesis in neighboring ectoderm cells via secreted BMP antagonizers.

• Korean Journal of Environmental Agriculture
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• v.40 no.3
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• pp.179-185
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• 2021

BACKGROUND: Tomato genome editing using CRISPR-Cas9 is being actively conducted in recent days, and lots of plant researches have been aiming to develop high valued crops by editing target genes without inserting foreign genes. Many researchers have been involved in the manipulation of the crop ripening process because fruit ripening is an important fruit phenotype for increasing fruit shelf life, taste, and texture of crops. This paper intends to evaluate target sgRNA to edit the two ripening-related genes encoding pectate lyase (PL) and phytoene synthase (Psy) with the CRISPR-Cas9 system. METHODS AND RESULTS: The CRISPR-Cas9 expression vector was cloned to target the PL (Solyc03g111690), Psy1 (Solyc03g031860), and Psy2 (Solyc02g081330) genes, which are the ripening genes of tomatoes. Tomatoes injected with Agrobacterium containing the CRISPR-Cas9 expression vector were further cultured for 5 days and used to check gene editing efficiency. As a result of the target gene sequence analysis by the next generation sequencing method, gene editing efficiency was calculated, and the efficient target location was selected for the PL and Psy genes. CONCLUSION: Therefore, this study was aimed to establish target sgRNA data that could have higher efficiency of the CRISPR-Cas9 system to obtain the delayed ripening phenotype of tomato. The developed method and sgRNA information is expected to be utilized in the development of various crops to manage its ripening processes.