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31.
32.
Jun Hyung Seo Hyo Geun Bae Da Hee Park Beom Seok Kim Jong Wook Lee Jung In Lee Dong Hyun Kim Seok Won Lee Bong Bo Seo 《Genes & genomics.》2013,35(1):117-124
Numerous studies on Oenothera species have been investigated for the physiological and ecological characteristics. However, no such an information based on molecular cytogenetic has yet been introduced, in turn, is very essential for identifying sequence polymorphisms of rRNA genes with their loci on mitotic phases for further biological researches. In this study, sequence variations of rRNA genes in Oenothera odorata and O. laciniata were examined to identify informative factors as unique or repeat sequences in intra- and inter-specific variations. Intra-specific variation revealed that the sequences of the rRNA genes including the spacer regions were highly conserved revealing only a few variations. From the inter-specific variation, spacer regions of species were completely different as (1) non-homologous sequences in NTS and (2) different type repeat sequences in ITS 1, 2 and 5.8S rRNA, whereas the remaining coding regions were highly conserved. FISH was carried out on mitotic phases using the 5S rDNA of the analyzed sequences. From the interphase and metaphase chromosomes of the examined species, two loci of 5S rDNA in O. odorata and four loci in O. laciniata were confirmed on the telomeric region of the short arm. Due to the small size and unclear centromere of the chromosomes, karyotype could not be completed. However, we confirmed that the chromosomes are organized by meta- and acrocentric chromosomes and the chromosomes with identified loci were assumed to be paired by the location of loci at the telomeric region on the short arm with relative lengths. 相似文献
33.
34.
Suk K Kim S Kim YH Oh SH Lee MK Kim KW Kim HD Seo YS 《Biochimica et biophysica acta》2000,1501(1):63-69
The cDNA library of human pancreatic islets was screened with sera from patients with insulin-dependent diabetes mellitus (IDDM). From the library screening, we isolated a novel cDNA, RNA helicase-like protein (RHELP), which exhibited strong sequence homology to p68 RNA helicase, a prototypic member of the DEAD (Asp-Glu-Ala-Asp) box protein family. Sequence analysis of the cDNA revealed that RHELP contained DEAD sequence motif and other conserved motifs of the DEAD box protein family, indicating that RHELP is a new member of this family. DEAD box-containing proteins are involved in the RNA processing, ribosome assembly, spermatogenesis, embryogenesis, and cell growth and division. RHELP showed 42% and 44% amino acid sequence identity to human p68 RNA helicase and yeast DBP2 RNA helicase, respectively, among the DEAD box protein family. Northern blot analysis revealed that RHELP is expressed in most tissues including the liver, lung, tonsil, thymus, and muscle in addition to the pancreatic islets. In vivo or in vitro functions of RHELP as a putative RNA helicase and its potential role as a diabetic autoantigen need to be further investigated. 相似文献
35.
Jae-Bong Lee Eun-Ji Jung Hee-Bok Park Shil Jin Dong-Won Seo Moon-Suck Ko In-Cheol Cho Jun-Heon Lee Hyun-Tae Lim 《Molecular biology reports》2014,41(11):7167-7173
Most reproductive traits have low heritability and are greatly affected by environmental factors. Teat number and litter size are traits related to the reproduction ability of pigs. To identify quantitative trait loci (QTLs) for teat number traits, a genome-wide association study (GWAS) was conducted using an F2 intercross between Landrace and Korean native pigs. Genotype analysis was performed using the porcine SNP 60 K beadchip. The GWAS was performed using a mixed-effects model and linear regression approach. When a genome-wide threshold was determined using the Bonferroni method (P = 1.61 × 10?6), 38 single nucleotide polymorphism (SNP) markers in pig chromosome 7 (SSC7) were significantly associated with three teat number traits (total teat number, left teat number, and right teat number). Among these, SNPs in 5 genes (HDDC3, LOC100156276, LOC100155863, ANPEP, SCAMP2) were selected for further study based primarily on their statistical significance. A significant association was detected in SCAMP2 g.25280 G>A for total teat number (P = 2.0 × 10?12), HDDC3 g.1319 G>A SNP for left teat number (P = 2.3 × 10?7), and SCAMP2 g.14198 G>A for right teat number (P = 4.7 × 10?12). These results provide valuable information about the selective breeding for desirable teat numbers in pigs. 相似文献
36.
de Paula RM Lewis ZA Greene AV Seo KS Morgan LW Vitalini MW Bennett L Gomer RH Bell-Pedersen D 《Journal of biological rhythms》2006,21(3):159-168
In Neurospora crassa, FRQ, WC-1, and WC-2 proteins comprise the core circadian FRQ-based oscillator that is directly responsive to light and drives daily rhythms in spore development and gene expression. However, physiological and biochemical studies have demonstrated the existence of additional oscillators in the cell that function in the absence of FRQ (collectively termed FRQ-less oscillators [FLOs]). Whether or not these represent temperature-compensated, entrainable circadian oscillators is not known. The authors previously identified an evening-peaking gene, W06H2 (now called clock-controlled gene 16 [ccg-16]), which is expressed with a robust daily rhythm in cells that lack FRQ protein, suggesting that ccg-16 is regulated by a FLO. In this study, the authors provide evidence that the FLO driving ccg-16 rhythmicity is a circadian oscillator. They find that ccg-16 rhythms are generated by a temperature-responsive, temperature-compensated circadian FLO that, similar to the FRQ-based oscillator, requires functional WC-1 and WC-2 proteins for activity. They also find that FRQ is not essential for rhythmic WC-1 protein levels, raising the possibility that this WCFLO is involved in the generation of WC-1 rhythms. The results are consistent with the presence of 2 circadian oscillators within Neurospora cells, which the authors speculate may interact with each other through the shared WC proteins. 相似文献
37.
Nam Jin Noh Yowhan Son Sue Kyoung Lee Tae Kyung Yoon Kyung Won Seo Choonsig Kim Woo-Kyun Lee Sang Won Bae Jaehong Hwang 《Journal of plant research》2010,123(4):411-419
We investigated the influence of stand density [938 tree ha−1 for high stand density (HD), 600 tree ha−1 for medium stand density (MD), and 375 tree ha−1 for low stand density (LD)] on soil CO2 efflux (R
S) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R
S measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature
(ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R
S (t C ha−1 year−1) and leaf litterfall (t C ha−1 year−1) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In
addition, R
S was correlated with ST (R
2 = 0.77–0.80, P < 0.001) and SWC (R
2 = 0.31–0.35, P < 0.001). It appeared that stand density influenced R
S via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R
2 = 0.71), TBCA (R
2 = 0.64–0.87), and total soil N contents in 2007 (R
2 = 0.94) explained a significant amount of the variance in R
S (P < 0.01). The current study showed that stand density is one of the key factors influencing R
S due to the changing biophysical and environmental factors in P. densiflora. 相似文献
38.
Ji-Hyeon Park Ji Hae Seo Hee-Jun Wee Tam Thuy Lu Vo Eun Ji Lee Hoon Choi Jong-Ho Cha Bum Ju Ahn Min Wook Shin Sung-Jin Bae Kyu-Won Kim 《PloS one》2014,9(8)
Arrest defective 1 (ARD1) is an acetyltransferase that is highly conserved across organisms, from yeasts to humans. The high homology and widespread expression of ARD1 across multiple species and tissues signify that it serves a fundamental role in cells. Human ARD1 (hARD1) has been suggested to be involved in diverse biological processes, and its role in cell proliferation and cancer development has been recently drawing attention. However, the subcellular localization of ARD1 and its relevance to cellular function remain largely unknown. Here, we have demonstrated that hARD1 is imported to the nuclei of proliferating cells, especially during S phase. Nuclear localization signal (NLS)-deleted hARD1 (hARD1ΔN), which can no longer access the nucleus, resulted in cell morphology changes and cellular growth impairment. Notably, hARD1ΔN-expressing cells showed alterations in the cell cycle and the expression levels of cell cycle regulators compared to hARD1 wild-type cells. Furthermore, these effects were rescued when the nuclear import of hARD1 was restored by exogenous NLS. Our results show that hARD1 nuclear translocation mediated by NLS is required for cell cycle progression, thereby contributing to proper cell proliferation. 相似文献
39.
Abu Hena Mostafa Kamal Ki-Hyun Kim Kwang-Hyun Shin Hyung-Seok Seo Hisashi Tsujimoto Hwa-Young Heo Jong-Soon Choi Chul-Soo Park Sun-Hee Woo 《Journal of Plant Biology》2009,52(6):533-542
Glutenin is a major determinant of baking performance and viscoelasticity, which are responsible for high-quality bread with
a light porous crumb structure of a well-leavened loaf. We analyzed the diversity of glutenin genes from six wheat cultivars
(Korean cvs. Keumgang and Jinpum, Chinese cvs. China-108 and Yeonnon-78, and Japanese cvs. Norin-61 and Kantou-107). Glutenins
contain two types of isoforms such as high molecular weight glutenin subunit (HMW-GS) and low molecular weight glutenin subunit
(LMW-GS). Glutenin fractions were extracted from wheat endosperm using Osborne solubility method. A total of 217 protein spots
were separated on two-dimensional gel electrophoresis with isoelectric focusing (wide range of pH 3–10). The proteins spots
were subjected to tryptic digestion and identified by matrix assisted laser desorption/ionization–time of flight mass spectrometry.
HMW-GS (43 isoforms) and LMW-GS (seven isoforms) are directly responsible for producing high-quality bread and noodles. Likewise,
all the seed storage proteins are digested to provide nutrients for the embryo during seed germination and seedling growth.
We identified the diverse glutenin subunits in wheat cultivars and compared the gluten isoforms among different wheat cultivars
according to quality. This work gives an insight on the quality improvement in wheat crop. 相似文献
40.
Nayoung Kim Soo‐Heon Park Geom Seog Seo Sang Woo Lee Jae Woo Kim Kwang Jae Lee Won‐Chang Shin Tae Nyeun Kim Moo‐In Park Jong‐Jae Park Su Jin Hong Ki‐Nam Shim Sang Wook Kim Yong‐Woon Shin Young‐Woon Chang Hoon Jai Chun Ok‐Jae Lee Won‐Joong Jeon Chan‐Guk Park Chang‐Min Cho Cheol Hee Park Sun Young Won Gin Hyug Lee Kyung Sik Park Jeong Eun Shin Heung Up Kim Joon Yong Park Hiun Suk Chae Geun Am Song Jae Gyu Kim Byung Chul Yoon Sangyong Seol Hyun Chae Jung In‐Sik Chung 《Helicobacter》2008,13(6):542-549
Background and Aims: Lafutidine is a novel H2‐receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7‐ or 14‐day lafutidine–clarithromycin–amoxicillin therapy versus a lansoprazole‐based regimen for Helicobacter pylori eradication. Methods: Four hundred and sixty‐three patients with H. pylori‐infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared. Results: The eradication rates by the intention‐to‐treat and per‐protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention‐to‐treat and per‐protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups. Conclusion: The results of this study showed that lafutidine–clarithromycin–amoxicillin therapy was a safe and effective as lansoprazole‐based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option. 相似文献