• Plant Biotechnology Reports
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• v.2 no.1
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• pp.47-58
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• 2008

To select agronomically useful transgenic plants, a large number of transgenic events are initially produced, gene transfer confirmed, and advanced to obtain homozygous lines for testing in field trials. Direct in planta assays for identifying the transgene carriers in the segregating progeny are based on the activity of selectable marker gene and are easy, simple and inexpensive. For this purpose, expression of bar gene as measured by tolerance to damage by glufosinate ammonium, the active ingredient in the herbicide BASTA, was investigated. Dose damage curves were generated by leaf paint tests with BASTA on four genotypes of sorghum. Transgenic plants were characterized in terms of sensitivity to the concentration of glufosinate ammonium. In transgenics, symptoms of BASTA swab tests at different growth stages and PCR analysis for cry1B were carried out and correlated. Germination tests could not be employed for large scale evaluation of transgenic progeny because of mortality of tolerant seedlings after transplantation to soil. Based on the above findings, a simple, inexpensive, time-saving, two-step scheme for effective evaluation of transgenics and their progeny containing bar gene as selection marker using BASTA swab tests is described.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.305-328
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• 1991

Pig breeding programs have been very successful in the improvement of animals by the simple expedient of focusing on a few traits of economic importance, particularly growth efficiency and leanness. Further reductions in leanness may become more difficult to achieve, due to reduced genetic variation, and less desirable, due to adverse correlated effects on meat and eating quality. Best linear unbiased prediction (BLUP) of breeding values makes possible the incorporation of data from many sources and increases the value of including traits such as sow performance in the breeding objective. Advances in technology, such as electronic animal identification, electronic feeders, improved ultrasonic scanners and automated data capture at slaughter houses, increase the number of sources of information that can be included in breeding value predictions. Breeding program structures will evolve to reflect these changes and a common structure is likely to be several or many breeding farms genetically linked by A.i., with data collected on a number of traits from many sources and integrated into a single breeding value prediction using BLUP. Future developments will include the production of a porcine gene map which may make it possible to identify genes controlling economically valuable traits, such as those for litter size in the Meishan, and introgress them into nucleus populations. Genes identified from the gene map or from other sources will provide insight into the genetic basis of performance and may provide the raw material from which transgenic programs will channel additional genetic variance into nucleus populations undergoing selection.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.540-546
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• 2010

This study was conducted to understand the role of soybean pathogenesis-related 10 (GmPR10) gene in salt tolerance and to develop salt-tolerant rice using GmPR10 cDNA. GmPR10 transgene was expressed constitutively in the shoot and root of the $T_1$ transgenic rice plants. Interestingly, however, the levels of the transgene expression were increased temporally up to over four- to five-fold in the shoot and root by 125 mM NaCl treatment, peaking at six hours after the treatment and decreasing thereafter. Electrolyte leakage of leaf cells under 125 mM NaCl treatment was lower in all the transgenic lines than in the control variety, Dongjin-byeo. Ability of seedlings to recover from 125 mM NaCl treatment for two weeks was higher in the transgenic plants than in the control plants. These results demonstrated that GmPR10 had function to increase cell integrity and promote growth under the saline stress imposed by NaCl. The transgenic line GmPR10-3 which showed highest ability to recover from the saline stress could be used as a potential source for salt tolerance in rice breeding programs.

• Journal of Sericultural and Entomological Science
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• v.52 no.2
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• pp.117-122
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• 2014

On previous studies, we constructed a transgenic silkworm which produces the chimeric silk fused green fluorescent protein (EGFP), but the transgenic silkworm has decreased commercial feasible traits such as convenience of breeding and productivity of silk. In this study, we performed cross fertilization between green fluorescent silk transgenic silkworm and colored cocoon silkworm descents to make the transgenic the transgenic silkworm producing improved fluorescence cocoon. In the result, we found out a bit valuable cross fertilization manners ($female{\times}male$) in respect of silk productivity such as $T59B{\times}Jam26$, $Jam329{\times}T59W$, $T59W{\times}Jam329$, and $T59W{\times}Jam178$. The color-difference of offspring cocoons were measured according to different cross manners using by CIE Lab-based formulae with a X-rite VS450. In the result, the depth of green color of cocoons was a little high at cross manners as $Jam329{\times}T59W$, $T59W{\times}Jam178$. Meanwhile, the depth of yellow clolor of cocoons was remarkable at cross manners as $Jam178{\times}T59W$, $T59W{\times}Jam178$, respectively.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.427-438
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• 2020

Middle East respiratory syndrome coronavirus (MERS-CoV) infects the lower respiratory airway of humans, leading to severe acute respiratory failure. Unlike human dipeptidyl peptidase 4 (hDPP4), a receptor for MERS-CoV, mouse DPP4 (mDPP4) failed to support MERS-CoV infection. Consequently, diverse transgenic mouse models expressing hDPP4 have been developed using diverse methods, although some models show no mortality and/or only transient and mild-to-moderate clinical signs following MERS-CoV infection. Additionally, overexpressed hDPP4 is associated with neurological complications and breeding difficulties in some transgenic mice, resulting in impeding further studies. Here, we generated stable hDPP4-transgenic mice that were sufficiently susceptible to MERS-CoV infection. The transgenic mice showed weight loss, decreased pulmonary function, and increased mortality with minimal perturbation of overexpressed hDPP4 after MERS-CoV infection. In addition, we observed histopathological signs indicative of progressive pulmonary fibrosis, including thickened alveolar septa, infiltration of inflammatory monocytes, and macrophage polarization as well as elevated expression of profibrotic molecules and acute inflammatory response in the lung of MERS-CoV-infected hDPP4-transgenic mice. Collectively, we suggest that this hDPP4-transgenic mouse is useful in understanding the pathogenesis of MERS-CoV infection and for antiviral research and vaccine development against the virus.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.425-441
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• 2010

Forages are the backbone of sustainable agriculture. They includes a wide variety of plant species ranging from grasses, such as tall fescue and bermudagrass, to herbaceous legumes, such as alfalfa and white clover. Abiotic stresses, especially salinity, drought, temperature extremes, high photon irradiance, and levels of inorganic solutes, are the limiting factors in the growth and productivity of major cultivated forage crops. Given the great complexity of forage species and the associated difficulties encountered in traditional breeding methods, the potential from molecular breeding in improving forage crops has been recognized. Plant engineering strategies for abiotic stress tolerance largely rely on the gene expression for enzymes involved in pathways leading to the synthesis of functional and structural metabolites, proteins that confer stress tolerance, or proteins in signaling and regulatory pathways. Genetic engineering allows researchers to control timing, tissue-specificity, and expression level for optimal function of the introduced genes. Thus, the use of either a constitutive or stress-inducible promoter may be useful in certain cases. In this review, we summarize the recent progress made towards the development of transgenic forage plants with improved tolerance to abiotic stresses.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.4
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• pp.482-485
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• 2006

Korean native goats have lived on the Korean peninsula for more than 2,000 years and are regarded as a valuable genetic resource for the world. As an initial step to investigate the genetic structures of this breed, phylogenetic analysis and calculation of genetic diversities have been performed using mitochondrial DNA (mtDNA) sequence variations. A total of 19 Korean native goats were grouped into six haplotypes and the large majority of haplotypes were present in 13 animals. All mtDNA of these Korean goats belonged to the mitochondrial (mt) lineage A and revealed remarkably small genetic distances within the population when compared with other Asian goat populations, indicating less genetic variation in the Korean native goats. These results indicate high-inbred status of the Korean native goats and will influence breeding and conservation strategies adopted for this breed.

• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.88-101
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• 2013

Eating quality of rice attracts more and more attention from rice-eating consumers in the recent years. Thus, improvement of eating quality of cooked rice has become one of the most important breeding goals in japonica rice. Here, the generation of transgenic japonica rice with improved eating quality and grain yield are reported. Overexpression of OsSbe1 gene encoding rice starch branching enzyme 1 was driven by 35S promoter. Eleven independent homozygous $T_3$ transgenic lines were characterized and had shown higher palatability (71.2 ~ 72.6) than wild type Gopum (70.4). Moreover, transgenic rice lines showed an increase in 1000-grain weight and number of spikelets per panicle compared with the wild type. The yield of milled rice was 562.8 ~ 596.7 kg/10a in eight $T_3$ lines, but 542.1 kg/10a in wild type. Gene expression analyses in mRNA transcription and enzyme activity levels suggest that improved eating quality is due to the up-regulation of OsSbe1 gene.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.261-270
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• 2009

Oxidative stress is a major damaging factor for plants exposed to environmental stresses. In order to develop transgenic rice plants with enhanced tolerance to various environmental stresses, PsAPX1, the gene of ascorbate peroxidase isolated from Pisum sativum was expressed in chloroplast under the control of an oxidative stress inducible sweet potato peroxidase2 (SWPA2) promoter (referred to as PsAPX1 plants). PsAPX1 transgenic plants showed enhanced tolerance to various environmental stresses, such as 170 mM NaCl, UV-B, ozone, 20% PEG, and drought in compared with non-transgenic (NT) plants. These results suggest that chloroplast-targeted over-expression of PsAPX1 gene could be very useful strategy for developing transgenic rice plants with increased tolerance to environmental stresses.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.534-539
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• 2010

'Hongro' is early-mid maturing cultivar with good quality like 'Tsugaru' and it has not preharvest drop. The CAX1 gene was introduced into Korean apple cultivar 'Hongro' by Agrobacterium tumefaciens LBA4404 harboring pBI121 to obtain transgenic apple with enhanced Ca level. The CAX1 gene playing the role of $H^+/Ca^{2+}$ transporter from Arabidopsis thaliana increases Ca concentration in several plants. Regenerated transgenic lines were confirmed by polymerase chain reaction (PCR) analysis and Southern blot analysis of genomic DNA for the existence of CAX1 gene. Southern blot analysis of 'Hongro' transformants showed that two putative transgenic lines were integrated with CAX1 gene in genomic DNA. The CAX1 comparative expression levels of two transgenic lines were higher than that of non-transformant evaluated by comparative quantification analysis using a real-time PCR. These two lines were multiplied in vitro, and micro-grafted on apple rootstocks 'M.9' in the isolated greenhouse. Since two years after micro-grafting, the fruits came into bearing. Compared to Ca level of the non-transgenic 'Hongro', that of the CAX1 transgenic 'Hongro' in the flesh and leaves was higher.