• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.3
• /
• pp.313-318
• /
• 2009

TIAF1 is a TGF-${\beta}$1-induced anti-apoptotic factor that plays a critical role in blocking TNF (tumor necrosis factor) cytotoxicity in mouse fibroblasts and participates in TGF-${\beta}$-mediated growth regulation. In this study, we obtained the full-length cDNA sequence of the porcine TIAF1 gene. Real-time PCR further revealed that the TIAF1 gene was expressed at the highest level in liver and kidney with prominent expressions detected in uterus, and lower levels detected in heart, spleen, lung, stomach, small intestine, skeletal muscle and fat of Large White pigs. Sequence analysis indicated that a 6 base-pair deletion mutation existed in the exon of the TIAF1 gene between Meishan and Large White pigs. This mutation induced deletion of Gln and Val amino acids. PCR-RFLP was used to detect the polymorphism in 394 pigs of a "Large White${\times}$Meishan" $F_{2}$ resource population and four purebred pig populations. The frequencies of the A allele (with a 6 bp deletion) were dominant in Chinese Meishan and Bamei pigs, and the frequencies of the B allele (no 6 bp deletion) were dominant in Large White and Landrace pigs. Association analyses revealed that the deletion mutation had highly significant associations (p<0.01) with meat marbling score of the thorax-waist longissimus dorsi (LD) muscle (MM1) and intramuscular fat percentage (IMF), and significant associations (p<0.05) with carcass length (CL). The results presented here supply evidence that the 6 bp deletion mutation in the TIAF1 gene affects porcine meat quality and provides useful information for further porcine breeding.

• Journal of the Korean association of regional geographers
• /
• v.16 no.2
• /
• pp.100-109
• /
• 2010

The study examines two different sites to analyze the difference of stream channel profile between two different landuse areas on Neponset River, Boston, MA. Landuse represents the current status of land in terms of human, agricultural or forest, industry and environmental activity types. According to the previous research, forest and urban area are significantly distinguished in chemical characteristic, shape and bed load of the stream. On the chosen sites, I look at the cross-section profile, the slope, velocity, and roughness of the channels. With the data collected at the site I determined the value for the channel bed material using Manning's equation, and compared with the result of HEC-RAS model with the cross-section profile data I measured. In the forest area, water surface elevation and bed material obtained through Manning's equation are very close to HEC-RAS model result. However, in the resident area the Manning's 'n' value calculated much higher than assumption which was considered as cobble whose 'n' value is 0.03-0.06. The difference could be caused by unusual steep elevation on the site and the dam present down further. With the steep elevation upside of dam, there is critical-depth condition occurs. The difference of Manning's 'n' value reflects the difference of depth. HEC-RAS model was run to analyze the difference and the result shows that depth is 0.36 much less than 0.688 what I computed when the Manning's n value is 0.03(cobble) instead of the result of the study (0.13292). Beside, dam is a major source of fragmentation and degradation of stream, and it's possibly inferred upstream water levels are increased and stream velocity is decreased. This study is meaningful for introduction of HEC-RAS in geography field to analyze different sites with channel bed material, and it is going to be used more actively to manage river and river side.

• Microbiology and Biotechnology Letters
• /
• v.30 no.3
• /
• pp.235-240
• /
• 2002

Streptomycetes is a group of Gram-positive soil bacteria that growas a branching vegetative mycelium leading to the formation of spores, and display a physiological differenti-ation related to the synthesis of many secondary metabolites including antibiotics. Their complex life cycle and multicellular differentiation require various levels of regulation and types of signal transduction systems including eukaryotic-type serine/threonine protein kinases and prokaryotic-type histidine/aspartic acid protein kinases. Akt kinase that was found in cells is a sorine/threonine kinase controlling signal pathway for multi-tude of important cellular events. The activation or inactivation of Akt kinase in the cell is one of the critical regulatory points to deliver cell proliferation, differentiation, survival or apoptosis signal. To find the regula-tory protein homologous to Akt in Streptomyces, the fluorescien-labeled synthetic peptide (FITC-TRRSR-TESIT) was designed from the consensus sequence of target proteins for Akt kinase. From the difference of the mobility between the nonphosphorylated and phosphorylated synthetic peptides on Agarose gel electro-phoresis, the Akt-phosphorylating activity was monitored. The cell-free extract prepared from Streptomyces griseus IFO 13350 and the Akt homologous protein was purified by ammonium sulfate fractionation and many steps of column chromatographies such as, DEAE-Sepharose, Mono Q, Resource Phenyl-Soporose and Gel permeation column chromatographies. As a result, the protein phosphorylating the fluorescien-labeled Akt substrate was identified and it's molecular weight was estimated as 39 kDa on SDS-PAGE.

• Microbiology and Biotechnology Letters
• /
• v.37 no.3
• /
• pp.287-292
• /
• 2009

The nucleocapsid (N) protein of porcine reproductive and respiratory syndrome virus (PRRSV) is a basic multifunctional protein which has been reported to be a serine phosphoprotein with yet-identified functions. As a first step towards understanding the general role of N protein phosphorylation during virus replication, the non-phosphorylated mutant N gene was constructed by mutating all serine residues to alanine. This recombinant N protein was identified to be unphosphorylated, confirming that serine residues truly function as core amino acids responsible for N protein phosphorylation. The PRRSV N protein has been shown to possess the biological features of nuclear localization and N-N homodimerization which individually play critical roles in virus infection. In the present study, therefore, it was attempted to investigate whether these two properties of the N protein are modulated by its phosphorylation status. However, experimental results showed that the non-phosphorylated N protein was still present in the nucleus and nucleolus, and was able to associate with itself by non-covalent interactions. Taken together, the data suggest phosphorylation-independent regulation of N protein nuclear transport or oligomerization, thereby implying the potential involvement of phosphorylation in regulating the activities of the N protein at other levels including RNA-binding capacity.

• Journal of Nutrition and Health
• /
• v.40 no.1
• /
• pp.14-23
• /
• 2007

Elevated plasma homocysteine (Hcy) is a risk factor for cognitive dysfunction and Alzheimer disease, although the mechanism is still unknown. Both folate and betaine, a choline metabolite, play essential roles in the remethylation of Hcy to methionine. Choline deficiency may be associated with low folate status and high plasma Hcy. Alterations in DNA methylation also have established critical roles for methylation in development of the nervous system. This study was undertaken to assess the effect of choline and folate deficiency on Hcy metabolism and genomic DNA methylation status of the liver and brain. Groups of adult male Sprague Dawley rats were fed on a control, choline-deficient (CD), folate-deficient (FD) or choline/folate-deficient (CFD) diets for 8 weeks. FD resulted in a significantly lower hepatic folate (23%) (p<0.001) and brain folate (69%) (p<0.05) compared to the control group. However, plasma and brain folate remained unaltered by CD and hepatic folate reduced to 85% of the control by CD (p<0.05). Plasma Hcy was significantly increased by FD $(18.34{\pm}1.62{\mu}M)$ and CFD $(19.35{\pm}3.62{\mu}M)$ compared to the control $(6.29{\pm}0.60{\mu}M)$ (p<0.001), but remained unaltered by CD. FD depressed S-adenosylmethionine (SAM) by 59% (p<0.001) and elevated S-adenosylhomocysteine (SAM) by 47% in liver compared to the control group (p<0.001). In contrast, brain SAM levels remained unaltered in CD, FD and CFD rats. Genomic DNA methylation status was reduced by FD in liver (p<0.05) Genomic DNA hypomethylation was also observed in brain by CD, FD and CFD although it was not significantly different from the control group. Genomic DNA methylation status was correlated with folate stores in liver (r=-0.397, p<0.05) and brain (r = -0.390, p<0.05), respectively. In conclusion, our data demonsoated that genomic DNA methylation and SAM level were reduced by folate deficiency in liver, but not in brain, and correlated with folate concentration in the tissue. The fact that folate deficiency had differential effects on SAM, SAH and genomic DNA methylation in liver and brain suggests that the Hcy metabolism and DNA methylation are regulated in tissue-specific ways.

• Journal of Nutrition and Health
• /
• v.14 no.2
• /
• pp.59-70
• /
• 1981

The objective of this study is to induce the primary characteristics of phenylketonuria in infant rats during the first 2 weeks after birth. The critical biochemical parameter in the development of phenylketonuria is the elevation of plasma phenylalanine while tyrosine is maintained at a relatively low level. A PKU-like condition was induced in infant rats during the first 2 weeks after birth using a modification of our previously published procedure for the development of a temporary (1 to 3 days) PKU-like condition. Phenylalanine was administered by stomach intubation every 6 hours (starting at 6:00 a.m.) at a dose level of 400mg per kg body weight (after birth-day 2 thru 5) and 500mg per kg body weight (day 6 thru 14). Amethopterin was given at 0.00625 or 0.0125mg per kg body weight (day 3 thru 14) and p-chlorophenylalanine at 50 mg per kg body weight (day 5 thru 14) at 9:00 a.m. and 9:00 p.m. At the times measured (6,10 and 14 days) plasma phenylalanine/tyrosine (P/T) ratios were elevated from a normal value of the or less to values ranging from 6 to 15. During the second week after birth a staggering gait, abnormal stance and decreased social behavior were also observed. None of these PKU-like characteristics were apparent in the three control groups receiving (a) no phenylalanine or inhibitors, (b) phenylalanine alone, or (c) inhibitors alone. The establishment of these primary biochemical characteristics of phenylketonuria by stomach intubation of phenylalanine and a combination of low dose levels of enzyme inhibitors to infant rats provides an experimental system which should he valuable for extensive biochemical, histological and behavioral studies in phenylketonuria.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.8
• /
• pp.1461-1471
• /
• 2017

Escherichia coli heat-labile enterotoxin (LT) and its non-toxic mutant (LTm) are well-known powerful mucosal adjuvants and immunogens. However, the yields of these adjuvants from genetically engineered strains remain at extremely low levels, thereby hindering their extensive application in fundamental and clinical research. Therefore, efficient production of these adjuvant proteins from genetically engineered microbes is a huge challenge in the field of molecular biology. In order to explore the expression bottlenecks of LTm in E. coli, we constructed a series of recombinant plasmids based on various considerations and gene expression strategies. After comparing the protein expression among strains containing different recombinant plasmids, the signal sequence was found to be critical for the expression of LTm and its subunits. When the signal sequence was present, the strong hydrophobicity and instability of this amino acid sequence greatly restricted the generation of subunits. However, when the signal sequence was removed, abundantly expressed subunits formed inactive inclusion bodies that could not be assembled into the hexameric native form, although the inclusion body subunits could be refolded and the biological activity recovered in vitro. Therefore, the dilemma choice of signal sequence formed bottlenecks in the expression of LTm. These results reveal the expression bottlenecks of LTm, provide guidance for the preparation of LTm and its subunits, and certainly help to promote efficient preparation of this mucosal adjuvant protein.

• Journal of Korean Society of Environmental Engineers
• /
• v.34 no.12
• /
• pp.855-862
• /
• 2012

Caenorhabditis elegans, a free-living nematode mainly found in the soil pore water, roles the critical function in trophic levels, energy flow, and decomposition in soil ecosystem. C. elegans is commonly used species to test soil toxicity. Recently, they are employed broadly as a test organism in nanotoxicology. In this study, a review of the toxicity of nanomaterials for C. elegans was presented based on SCI (E) papers. The nanotoxicity studies using C. elegans have been reported in 20 instances including the mechanism of toxicity. Most studies used K-medium, S-medium, and NGM (Nematode Growth Medium) plate as an exposure medium to test toxicity of nanoparticles. The effects observed include anti aging, phototoxicity, genotoxicity, and dermal effects on C. elegans exposed to nanoparticles. We found that the toxic mechanisms were related with various aspects such as lifespan abnormality, oxidative stress, distribution of particles on inter-organisms, and stress-related gene analysis. C. elegans has advantage to test toxicity of nanoparticles due to various cellular activities, full genome information, and easy observation of transparent body. C. elegans was considered to be a good test species to evaluate the nanotoxicity.

• Korean Journal of Veterinary Service
• /
• v.25 no.2
• /
• pp.117-126
• /
• 2002

Contamination levels of pathogenic microorganisms in 145 cases of beef, which were distributed in Gwangju province, had been investigated in each distributed stage and also monitored by general bacterial count and E coli count index. General bacterial count of beef from the slaughterhouse was 10$^4$cfu/g less than the level of promotion(10 cfu/$\textrm{cm}^2$) and E coli count index was also under the level of 10$^2$cfu/$\textrm{cm}^2$ recommended level of the ministry of agriculture and forestry. Pathogenic microorganisms were detected from 23.2% of samples in the consumption stage, 12.5% in the slaughtering stage and 5.6% in the transporting and processing stage. Staphylococcus aureus was isolated in the largest number and its ratio was 9.0%, listeria monocytogenes 5.5% and salmonella spp 1.4%. There were no samples that bacteria had been detected dually. E coli O157:H7 and campylobacter jejuni were not isolated. In raw and chilled beef, isolation rate of pathogenic microorganisms were 13.3% and 16.5% each. Especially in raw beef, L monocytogenes was. isolated in 3 samples among 30 cases (10%) and S aureus in one sample (3.3%). According to a scale of meat store, isolation rates of pathogenic microorganisms were different. It was 28.6% in the small-scale meat store and 16.7% in the large-scale meat store each. Four cases (16.7%) of S aureus were isolated in the large-scale meat store and seven cases (20.0%) of L monocytogenes and 2 cases (5.7%) of salmonella spp were isolated in the small-scale meat store. S aureus was isolated in two places among 10 feeding facilities of the elementary school. This result shows that the sanitation of elementary school feeding facilities is so poor and more careful policy consideration is needed. Eleven strains of S aureus isolated showed ${\beta}$-hemolysis on blood agar, 1 strain ${\alpha}$-hemolysis, and 1 strain ${\gamma}$-hemolysis. Isolated strains of L monocytogenes were reconfirmed in 560 bp by PCR. Conclusively, these results show that the sanitary condition in the stages of slaughtering, transportation-processing and consumption influences the degree of pathogenic microorganisms contamination in beef severely It is necessary to apply thoroughly hazard analysis critical control point in a process of beef distribution and also to develop rapid test methods for microorganism diagnosis. This effort is very important for the supply of safe and clean meat from farm to table and helpful for the improvement of public health.

• Korean Journal of Weed Science
• /
• v.2 no.2
• /
• pp.114-121
• /
• 1982

Sagittaria pygmaea Miquel is widely infested and is the most dominant perennial weed in paddy field in Korea. This study was carried out in order to clarify the factors influencing tuber production and the competition ecology. The tuberization capacity in the paddy field transplanted with the small seedlings of rice was higher than in the paddy field transplanted with the vigor seedlings of rice. The stage which rice plants were most damaged by S. pygmaea plants was the period from 31 to 37 days after transplanting. According to the increasing of Eleocharis acicularis Roem. in the condition of rice cultivation, the number of S. pygmaea plants was remarkably reduced. Small size tubers planted within deep soil produced less tubers than large size tubers did. The number of plants and tubers were remarkably increased under the high levels of fertilization. Phosphorus was essential as well as nitrogen for tuberization. And the tuberization capapcity was different with the organic matter content in soil and with the soil moisture.