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11.
William J. Sames Terry A. Klein Heung Chul Kim Sung Tae Chong In Yong Lee Se Hun Gu Yon Mi Park Ji Hye Jeong Jin‐Won Song 《Journal of vector ecology》2009,34(2):225-231
The Twin Bridges Training Area (TBTA) in the Republic of Korea consists of dirt roads, barren training areas, and forested hillsides adjacent to linear and broad expanses of tall grasses, herbaceous, and scrub vegetation. Of the six species of small mammals, the striped field mouse, Apodemus agrarius, was the most frequently captured (96.1%). Apodemus agrarius capture rates varied from 17.7 to 33.2% during three trapping periods. Gravid females were observed during November‐December 2006 (8.4%) and March 2007 (5.1%). In 2005, the overall seroprevalence of Hantaan virus (HTNV) was high (34.4%) and lower during surveys in 2006 (14.2%) and 2007 (13.8%). Seroprevalence was directly correlated with weight increase of A. agrarius. 相似文献
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Jun Seong Jeong Min Jee Kim Jeong Sun Park Keon Hee Lee Yong Hun Jo Jun-ichi Takahashi Yong Soo Choi Iksoo Kim 《Journal of Asia》2021,24(2):135-147
The yellow-legged hornet, Vespa velutina nigrithorax (Hymenoptera: Vespidae), invaded South Korea in 2003 through Busan metropolitan city, which is located in the southeast region of the country. Previous studies aiming to trace the origin of V. velutina in Korea used a portion of mitochondrial (mt) COI and detected a single haplotype common to the site of origin. However, no subsequent study on invasive dynamics such as additional entry and/or another site of entry has been performed. In this study, segments of mt COI, CytB, and lrRNA were sequenced from 238 individuals collected in 11 Korean and two Japanese localities, but no variation in each gene was observed. Thus, we developed two intergenic spacer (IGS) sequences from the publicly available mt genome of V. velutina, which provided substantially increased variability (i.e., 19 haplotypes with 1.74% maximum sequence divergence in 1,129–1,146-bp-long concatenated sequences). Population genetic analyses using the concatenated sequences unexpectedly provided higher genetic diversity estimates in the northwest and southwest regions, both of which also harbor international cargo ports, than in the southeast region, in which Busan is located. Furthermore, this genetic result was roughly concordant with our questionnaire survey demonstrating that V. velutina was observed in apiaries located in the northwest and southwest regions up to 2012, when there was no reported prevalent distribution of the hornet beyond the southeast region. These results collectively suggest that the northwest and southwest regions of Korea are additional sites of V. velutina entry to the country, independent from the southeast region origin. 相似文献
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Dong Hyun Jo Chang Sik Cho Jin Hyoung Kim Hyoung Oh Jun Jeong Hun Kim 《Journal of biomedical science》2013,20(1):38
Effective and validated animal models are valuable to investigate the pathogenesis and potential therapeutics for human diseases. There is much concern for diabetic retinopathy (DR) in that it affects substantial number of working population all around the world, resulting in visual deterioration and social deprivation. In this review, we discuss animal models of DR based on different species of animals from zebrafish to monkeys and prerequisites for animal models. Despite criticisms on imprudent use of laboratory animals, we hope that animal models of DR will be appropriately utilized to deepen our understanding on the pathogenesis of DR and to support our struggle to find novel therapeutics against catastrophic visual loss from DR. 相似文献
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Defining the molecular composition of caveolae is essential in establishing their molecular architecture and functions. Here, we identify a high affinity monoclonal antibody that is specific for caveolin-1alpha and rapidly binds caveolin oligomerized around intact caveolae. We use this antibody (i) to develop a new simplified method for rapidly isolating caveolae from cell and tissue homogenates without using the silica-coating technology and (ii) to analyze various caveolae isolation techniques to understand how they work and why they yield different compositions. Caveolae are immunoisolated from rat lung plasma membrane fractions subjected to mechanical disruption. Sonication of plasma membranes, isolated with or without silica coating, releases caveolae along with other similarly buoyant microdomains and, therefore, requires immunoisolations to purify caveolae. Shearing of silica-coated plasma membranes provides a homogeneous population of caveolae whose constituents (i) remain unchanged after immunoisolation, (ii) all fractionate bound to the immunobeads, and (iii) appear equivalent to caveolae immunoisolated after sonication. The caveolae immunoisolated from different low density fractions are quite similar in molecular composition. They contain a subset of key signaling molecules (i.e. G protein and endothelial nitric oxide synthase) and are markedly depleted in glycosylphosphatidylinositol-anchored proteins, beta-actin, and angiotensin-converting enzyme. All caveolae isolated from the cell surface of lung microvascular endothelium in vivo appear to be coated with caveolin-1alpha. Caveolin-1beta and -2 can also exist in these same caveolae. The isolation and analytical procedures as well as the time-dependent dissociation of signaling molecules from caveolae contribute to key compositional differences reported in the literature for caveolae. This new, rapid, magnetic immunoisolation procedure provides a consistent preparation for use in the molecular analysis of caveolae. 相似文献
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Plant gene responses to frequency-specific sound signals 总被引:1,自引:0,他引:1
Mi-Jeong Jeong Chang-Ki Shim Jin-Ohk Lee Hawk-Bin Kwon Yang-Han Kim Seong-Kon Lee Myeong-Ok Byun Soo-Chul Park 《Molecular breeding : new strategies in plant improvement》2008,21(2):217-226
We identified a set of sound-responsive genes in plants using a sound-treated subtractive library and demonstrated sound regulation
through mRNA expression analyses. Under both light and dark conditions, sound up-regulated expression of rbcS and ald. These are also light-responsive genes and these results suggest that sound could represent an alternative to light as a
gene regulator. Ald mRNA expression increased significantly with treatment at 125 and 250 Hz, whereas levels decreased significantly with treatment
at 50 Hz, indicating a frequency-specific response. To investigate whether the ald promoter responds to sound, we generated transgenic rice plants harboring a chimeric gene comprising a fusion of the ald promoter and GUS reporter. In three independent transgenic lines treated with 50 or 250 Hz for 4 h, GUS mRNA expression was up-regulated at 250 Hz, but down-regulated at 50 Hz. Thus, the sound-responsive mRNA expression pattern
observed for the ald promoter correlated closely with that of ald, suggesting that the 1,506 bp ald promoter is sound-responsive. Therefore, we propose that in transgenic plants, specific frequencies of sound treatment could
be used to regulate the expression of any gene fused to the ald promoter. 相似文献
20.
Seong-Ok Lee Kwangmin Cho Sunglim Cho Ilkwon Kim Changhoon Oh Kwangseog Ahn 《The EMBO journal》2010,29(2):363-375
The human cytomegalovirus glycoprotein US2 induces dislocation of MHC class I heavy chains from the endoplasmic reticulum (ER) into the cytosol and targets them for proteasomal degradation. Signal peptide peptidase (SPP) has been shown to be integral for US2-induced dislocation of MHC class I heavy chains although its mechanism of action remains poorly understood. Here, we show that knockdown of protein disulphide isomerase (PDI) by RNA-mediated interference inhibited the degradation of MHC class I molecules catalysed by US2 but not by its functional homolog US11. Overexpression of the substrate-binding mutant of PDI, but not the catalytically inactive mutant, dominant-negatively inhibited US2-mediated dislocation of MHC class I molecules by preventing their release from US2. Furthermore, PDI associated with SPP independently of US2 and knockdown of PDI inhibited SPP-mediated degradation of CD3δ but not Derlin-1-dependent degradation of CFTR DeltaF508. Together, our data suggest that PDI is a component of the SPP-mediated ER-associated degradation machinery. 相似文献