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61.
Yi SS Hwang IK Yoo KY Park OK Yu J Yan B Kim IY Kim YN Pai T Song W Lee IS Won MH Seong JK Yoon YS 《Neurochemical research》2009,34(6):1039-1046
In the present study, we investigated the effects of a treadmill exercise on serum glucose levels and Ki67 and doublecortin
(DCX) immunoreactivity, which is a marker of cell proliferation expressed during cell cycles except G0 and early G1 and a
marker of progenitors differentiating into neurons, respectively, in the subgranular zone of the dentate gyrus (SZDG) using
a type II diabetic model. At 6 weeks of age, Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats were put on a
treadmill with or without running for 1 h/day/5 consecutive days at 22 m/min for 5 weeks. Body weight was significantly increased
in the control (without running)-ZDF rats compared to that in the other groups. In the control groups blood glucose levels
were increased by 392.7 mg/dl in the control-ZDF rats and by 143.3 mg/dl in the control-ZLC rats. However, in the exercise
groups, blood glucose levels were similar between the exercise-ZLC and ZDF rats: The blood glucose levels were 110.0 and 118.2 mg/dl,
respectively. Ki67 positive nuclei were detected in the SZDG in control and exercise groups. The number of Ki67 positive nuclei
was significantly high in exercise groups compared to that in the control groups. In addition, Ki67 positive cells were abundant
in ZLC groups compared to those in ZDF groups. DCX-immunoreactive structures in the control-ZDF rats were lower than that
in the control-ZLC rats. In the exercise groups, DCX-immunoreactive structures (somata and processes with tertiary dendrites)
and DCX protein levels were markedly increased in both the exercise-ZLC and ZDF rats compared to that in the control groups.
These results suggest that a treadmill exercise reduces blood glucose levels in ZDF rats and increases cell proliferation
and differentiation in the SZDG in ZLC and ZDF rats compared to those in control groups. 相似文献
62.
Evaluation of formulations of Bacillus licheniformis for the biological control of tomato gray mold caused by Botrytis cinerea 总被引:2,自引:0,他引:2
Jae Pil Lee Seon-Woo Lee Choul Sung Kim Ji Hee Son Ju Hee Song Kwang Youll Lee Hyun Ju Kim Soon Je Jung Byung Ju Moon 《Biological Control》2006,37(3):329-337
Bacillus licheniformis N1, which has previously exhibited potential as a biological control agent, was investigated to develop a biofungicide to control the gray mold of tomato caused by Botrytis cinerea. Various formulations of B. licheniformis N1 were developed using fermentation cultures of the bacteria in Biji medium, and their ability to control gray mold on tomato plants was evaluated. The results of pot experiments led to the selection of the wettable powder formulation N1E, based on corn starch and olive oil, for evaluation of the disease control activity of this bacterium after both artificial infection of the pathogen and natural disease occurrence under production conditions. In plastic-house artificial infection experiments, a 100-fold diluted N1E treatment was found to be the optimum biofungicide spray formulation. This treatment resulted in the significant reduction of symptom development when N1E was applied before Bo. cinerea infection, but not after the infection. Both artificial infection experiments in a plastic house and natural infection experiments under production conditions revealed that the N1E significantly reduced disease severity on tomato plants and flowers. The disease control value of N1E on tomato plants was 90.5% under production conditions, as compared to the 77% conferred by a chemical fungicide, the mixture of carbendazim and diethofencarb (1:1). The prevention of flower infection by N1E resulted in increased numbers of tomato fruits on each plant. N1E treatment also had growth promotion activity, which showed the increased number of tomato fruits compared to fungicide treatment and non-treated control and the increased fruit size compared the non-treated control under production conditions. This study suggests that the corn starch-based formulation of B. licheniformis developed using liquid fermentation will be an effective tool in the biological control of tomato gray mold. 相似文献
63.
Flavonoid glycosides are highly attractive targets due to their dominant roles in clinical, cosmetic production and in the food industry. In this research, an Escherichia coli strain bearing the reconstructed uridine-diphosphate glucose (UDP-glucose) pathway cassette and a putative glycosyltransferase from Arabidopsis thaliana, was developed as a host for the production of apigenin-7-O-β-d-glucoside (APG) and baicalein-7-O-β-d-glucoside (BCG) from exogenously supplied flavone aglycones (apigenin and baicalein, respectively). In order to improve the yield, genetic engineering of E. coli strains for optimization of intracellular UDP-glucose generation, as well as media optimization were carried out. The production was scaled up using a fed batch fermentation, and the maximal yield of products reached 90.88 μM (39.28 mg L?1) and 76.82 μM (33.19 mg L?1) of APG and BCG, respectively. And, the maximum bioconversion rate corresponded to 90.88% and 76.82% of apigenin and baicalein, respectively. 相似文献
64.
Je Hyeong Jung Baskaran Kannan Hugo Dermawan Geoffrey W. Moxley Fredy Altpeter 《Plant molecular biology》2016,92(4-5):505-517
Sugarcane (Saccharum spp. hybrids) is a major feedstock for commercial bioethanol production. The recent integration of conversion technologies that utilize lignocellulosic sugarcane residues as well as sucrose from stem internodes has elevated bioethanol yields. RNAi suppression of lignin biosynthetic enzymes is a successful strategy to improve the saccharification of lignocellulosic biomass. 4-coumarate:coenzyme A ligase (4CL) is a key enzyme in the biosynthesis of phenylpropanoid metabolites, such as lignin and flavonoids. Identifying a major 4CL involved in lignin biosynthesis among multiple isoforms with functional divergence is key to manipulate lignin biosynthesis. In this study, two full length 4CL genes (Sh4CL1 and Sh4CL2) were isolated and characterized in sugarcane. Phylogenetic, expression and RNA interference (RNAi) analysis confirmed that Sh4CL1 is a major lignin biosynthetic gene. An intragenic precision breeding strategy may facilitate the regulatory approval of the genetically improved events and was used for RNAi suppression of Sh4CL1. Both, the RNAi inducing cassette and the expression cassette for the mutated ALS selection marker consisted entirely of DNA sequences from sugarcane or the sexually compatible species Sorghum bicolor. Field grown sugarcane with intragenic RNAi suppression of Sh4CL1 resulted in reduction of the total lignin content by up to 16.5?% along with altered monolignol ratios without reduction in biomass yield. Mature, field grown, intragenic sugarcane events displayed 52–76?% improved saccharification efficiency of lignocellulosic biomass compared to wild type (WT) controls. This demonstrates for the first time that an intragenic approach can add significant value to lignocellulosic feedstocks for biofuel and biochemical production. 相似文献
65.
Chae Oh Lim Soo In Lee Woo Sik Chung Sung Han Park Inhwan Hwang Moo Je Cho 《Plant molecular biology》1996,30(2):373-379
A cDNA encoding a new phytocystatin isotype named BCPI-1 was isolated from a cDNA library of Chinese cabbage flower buds. The BCPI-1 clone encodes 199 amino acids resulting in a protein much larger than other known phytocystatins. BCPI-1 has an unusually long C-terminus. A BCPI-1 fusion protein expressed in Escherichia coli strongly inhibits the enzymatic activity of papain, a cysteine proteinase. Genomic Southern blot analysis revealed that the BCPI gene is a member of a small multi-gene family in Chinese cabbage. Northern blot analysis showed that it is differentially expressed in the flower bud, leaf and root. 相似文献
66.
67.
Lee Seokjin Trịnh Cao Sơn Lee Won Je Jeong Chan Young Truong Hai An Chung Namhyun Kang Chon-Sik Lee Hojoung 《Journal of plant research》2020,133(2):231-244
Journal of Plant Research - Plant growth promoting rhizobacteria (PGPR) are a group of bacteria that promote plants growth in the rhizosphere. PGPRs are involved in various mechanisms that... 相似文献
68.
Mojca Jež Tuba Bas Matija Veber Andrej Košir Tanja Dominko Raymond Page Primož Rožman 《Histochemistry and cell biology》2013,139(1):195-204
Immunocytochemistry is a powerful tool for detection and visualization of specific molecules in living or fixed cells, their localization and their relative abundance. One of the most commonly used fluorescent DNA dyes in immunocytochemistry applications is 4′,6-diamidino-2-phenylindole dihydrochloride, known as DAPI. DAPI binds strongly to DNA and is used extensively for visualizing cell nuclei. It is excited by UV light and emits characteristic blue fluorescence. Here, we report a phenomenon based on an apparent photoconversion of DAPI that results in detection of a DAPI signal using a standard filter set for detection of green emission due to blue excitation. When a sample stained with DAPI only was first imaged with the green filter set (FITC/GFP), only a weak cytoplasmic autofluorescence was observed. Next, we imaged the sample with a DAPI filter set, obtaining a strong nuclear DAPI signal as expected. Upon reimaging the same samples with a FITC/GFP filter set, robust nuclear fluorescence was observed. We conclude that excitation with UV results in a photoconversion of DAPI that leads to detection of DAPI due to excitation and emission in the FITC/GFP channel. This phenomenon can affect data interpretation and lead to false-positive results when used together with fluorochrome-labeled nuclear proteins detected with blue excitation and green emission. In order to avoid misinterpretations, extra precaution should be taken to prepare staining solutions with low DAPI concentration and DAPI (UV excitation) images should be acquired after all other higher wavelength images. Of various DNA dyes tested, Hoechst 33342 exhibited the lowest photoconversion while that for DAPI and Hoechst 33258 was much stronger. Different fixation methods did not substantially affect the strength of photoconversion. We also suggest avoiding the use of mounting medium with high glycerol concentrations since glycerol showed the strongest impact on photoconversion. This photoconversion effect cannot be avoided even when using narrow bandpass filter sets. 相似文献
69.
Ming Shun Li Jong Yul Roh Xueying Tao Zi Niu Yu Zi Duo Liu Qin Liu Hong Guang Xu Hee Jin Shim Yang-Su Kim Yong Wang Jae Young Choi Yeon Ho Je 《Journal of microbiology (Seoul, Korea)》2009,47(4):466-472
Bacillus thuringiensis, an entomopathogenic bacterium belonging to the B. cereus group, harbors numerous extra-chromosomal DNA molecules whose sizes range from 2 to 250 kb. In this study, we used a plasmid capture system (PCS) to clone three small plasmids from B. thuringiensis subsp. kurstaki Kl which were not found in B. thuringiensis subsp. kurstaki HD-1, and determined the complete nucleotide sequence of plasmid pKlS-1 (5.5 kb). Of the six putative open reading frames (ORF2-ORF7) in pKlS-1, ORF2 (MobKl) showed approximately 90% aa identity with the Mob-proteins of pGI2 and pTX14-2, which are rolling circle replicating group VII (RCR group VII) plasmids from B. thuringiensis. In addition, a putative origin of transfer (oriT) showed 95.8% identity with those of pGI2 and pTX14-2. ORF3 (RepK1) showed relatively low aa identity (17.8~25.2%) with the Rep protein coded by RCR plasmids, however. The putative double-strand origin of replication (dso) and single-strand origin of replication (sso) of pKlS-1 exhibited approximately 70% and 64% identities with those of pGI2 and pTX14-2. ORF6 and 7 showed greater than 50% similarities with alkaline serine protease, which belongs to the subtilase family. The other 2 ORFs were identified as hypothetical proteins. To determine the replicon of pKlS-1, seven subclones were contructed in the B. thuringiensis ori-negative pHTIK vector and were electroporated into a plasmid cured B. thuringiensis strain. The 1.6 kb region that included the putative ORF3 (ReplK), dso and ORF4, exhibited replication ability. These findings identified pKlS-1 as a new RCR group VII plasmid, and determined its replication region. 相似文献
70.
Dayeon Yu Hyun-Soo Shin Go Choi Yong Chan Lee 《Molecular and cellular biochemistry》2014,396(1-2):213-220
CD44 is a cell surface protein and it is widely used as a cancer stem cell marker in various cancer types including gastric cancer. We conducted proteomic analysis in CD44(+) and CD44(?) gastric cancer cells to understand characteristics of CD44(+) and CD44(?) cells. In the present study, we sorted cells from the gastric cancer cell line MKN45 according to CD44 expression to separate out CD44(+) and CD44(?) cells. And we conducted RT-PCR to identify mRNA expression of cancer stem cell markers in CD44(+) and CD44(?) cells. Cancer stem cell markers showed upregulated expression in CD44(+) cells. Next, we performed two-dimensional electrophoresis analysis to determine the differential expression pattern of proteins in each group; control, CD44(+), and CD44(?) MKN45 cells. We found a total of 113 spots that varied in expression between CD44(+) and CD44(?) cells, and subjected 20 of those protein spots to MALDI-MS. We selected the three proteins (HSPA8; heat shock cognate 71 kDa protein isoform 1, ezrin, α-enolase) upregulated in CD44(+) cells than CD44(?) cells and one protein (prohibitin) showed increased expression in CD44(?) cells. We validated the protein expression levels of four selected proteins by Western blot. We suggest that our study could be a helpful background to study CD44(+) cancer stem-like cells and differences between CD44(+) and CD44(?) cells in gastric cancer. 相似文献