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91.
Reprogramming of the activity of the activator/dissociation transposon family during plant regeneration in rice 总被引:3,自引:0,他引:3
Ki CM Je BI Piao HL Par SJ Kim MJ Park SH Park JY Park SH Lee EK Chon NS Won YJ Lee GH Nam MH Yun DW Lee MC Cha YS Le Kon H Eun MY Han CD 《Molecules and cells》2002,14(2):231-237
Many aspects of epigenetic phenomena have been elucidated via studies of transposable elements. An active transposable element frequently loses its ability to mobilize and goes into an inactive state during development. In this study, we describe the cyclic activity of a maize transposable element dissociation (Ds) in rice. In rice genome, Ds undergoes the spontaneous loss of mobility. However, an inactive state of Ds can be changed into an active state during tissue culture. The recovery of mobility accompanies not only changes in the methylation patterns of the terminal region of Ds, but also alteration in the steady state level of the activator (Ac) mRNA that is expressed by a constitutive CaMV 35S promoter. Furthermore, the Ds-reactivation process is not random, but stage-specific during plantlet regeneration. Our findings have expanded previous observations on Ac reactivation in the tissue culture of maize. 相似文献
92.
93.
Hye Won Lee Chanho Park Je-Gun Joung Minyong Kang Yun Shin Chung Won Joon Oh Seon-Yong Yeom Woong-Yang Park Tae Jin Kim Seong Il Seo 《Current issues in molecular biology》2021,43(1):226
Due to the highly immunogenic nature of renal cell carcinoma (RCC), the tumor microenvironment (TME) is enriched with various innate and adaptive immune subsets. In particular, gamma-delta (γδ) T cells can act as potent attractive mediators of adoptive cell transfer immunotherapy because of their unique properties such as non-reliance on major histocompatibility complex expression, their ability to infiltrate human tumors and recognize tumor antigens, relative insensitivity to immune checkpoint molecules, and broad tumor cytotoxicity. Therefore, it is now critical to better characterize human γδ T-cell subsets and their mechanisms in RCCs, especially the stage of differentiation. In this study, we aimed to identify γδ T cells that might have adaptive responses against RCC progression. We characterized γδ T cells in peripheral blood and tumor-infiltrating lymphocytes (TILs) in freshly resected tumor specimens from 20 RCC patients. Furthermore, we performed a gene set enrichment analysis on RNA-sequencing data from The Cancer Genome Atlas (TCGA) derived from normal kidneys and RCC tumors to ascertain the association between γδ T-cell infiltration and anti-cancer immune activity. Notably, RCC-infiltrating CD3low Vγ9Vδ1 T cells with a terminally differentiated effector memory phenotype with up-regulated activation/exhaustion molecules were newly detected as predominant TILs, and the cytotoxic activity of these cells against RCC was confirmed in vitro. In an additional analysis of the TCGA RCC dataset, γδ T-cell enrichment scores correlated strongly with those for CTLs, Th1 cells, “exhausted” T cells, and M1 macrophages, suggesting active involvement of γδ T cells in anti-tumor rather than pro-tumor activity, and Vδ1 cells were more abundant than Vδ2 or Vδ3 cells in RCC tumor samples. Thus, we posit that Vγ9Vδ1 T cells may represent an excellent candidate for adoptive immunotherapy in RCC patients with a high risk of relapse after surgery. 相似文献
94.
KS Lee RN Kim BH Yoon DS Kim SH Choi DW Kim SH Nam A Kim A Kang KH Park JE Jung SH Chae HS Park 《Bioinformation》2012,8(11):532-534
Recently, next generation sequencing (NGS) technologies have led to a revolutionary increase in sequencing speed and costefficacy. Consequently, a vast number of contigs from many recently sequenced bacterial genomes remain to be accurately mapped and annotated, requiring the development of more convenient bioinformatics programs. In this paper, we present a newly developed web-based bioinformatics program, Bacterial Genome Mapper, which is suitable for mapping and annotating contigs that have been assembled from bacterial genome sequence raw data. By constructing a multiple alignment map between target contig sequences and two reference bacterial genome sequences, this program also provides very useful comparative genomics analysis of draft bacterial genomes. AVAILABILITY: The database is available for free at http://mbgm.kribb.re.kr. 相似文献
95.
Multi-target-multi-drug approaches are needed to accelerate the process of drug discovery screening and to design efficient therapeutic strategies against diseases that involve alterations in multiple cellular targets. Herein we report single-cell cotransfection imaging cytometry to quantitatively screen drug-induced off-target effects. Vascular endothelial growth factor (VEGF) and histone deacetylase (HDAC) genes amplified from the genomic DNA were cloned in fluorescently tagged gene constructs (RFP-HDAC/YFP-VEGF). These gene constructs were cotransfected in HEK-293 cells to explore the possibility of off-target effects of 4-phenylbutyrate and Iressa on the expression of VEGF and HDAC through single-cell imaging cytometry. Iressa (10 μM) treatment at the time of cotransfection or 48 h after cotransfection of RFP-HDAC/YFP-VEGF plasmids in HEK-293 cells resulted in off-target effects on HDAC expression. These results suggest possible applications of Iressa in the treatment of diseases in which expression of both HDAC and VEGF should be inhibited. 4-Phenylbutyrate (2.0 mM) did not show any off-target effects on VEGF expression. The developed quantitative multicolor live single-cell cotransfection imaging can be employed to select better drug combinations for faster screening and greater accuracy in multi-target-multi-drug analysis by increasing the on-target/desired off-target effects and eliminating the undesirable off-target effects. 相似文献
96.
Iyyakkannu Sivanesan Ju Yeon Song Seung Jae Hwang Byoung Ryong Jeong 《Plant Cell, Tissue and Organ Culture》2011,105(1):55-63
A simple and efficient micropropagation system was developed for Cotoneaster wilsonii through node and shoot tip explants obtained from mature field-grown plants. Of the two explants, node explants were found
to be the most effective for axillary shoot proliferation. The highest frequency of shoot induction was achieved when nodal
explants were incubated on Murashige and Skoog (MS) medium supplemented with 0.5 mg L−1 thidiazuron (TDZ) and 0.1 mg L−1 α- naphthaleneacetic acid (NAA) with an average of 34 shoots per explant. The microshoots were separated from the multiple
shoots and subcultured on MS medium supplemented with 3% (w/v) sucrose and 0.8% (w/v) agar for further shoot growth. Maximum
rooting was obtained on half-strength MS medium supplemented with 0.5 mg L−1 indole-3-butyric acid (IBA). The in vitro-grown plantlets were successfully acclimatized in a glasshouse with 98% of survival.
High concentrations of TDZ (1.5–2.0 mg L−1) and repeated subcultures resulted hyperhydric shoots. Supplementation of the culture medium with silicon significantly reduced
the induction of hyperhydric shoots. Increasing silicon concentration significantly decreased malondialdehyde content of the
regenerated shoots. Data indicate that addition of silicon to the culture medium can effectively control hyperhydricity. 相似文献
97.
Since the late 1960s, researchers have observed that starch in the chloroplasts of the guard cells breaks down during the
day and accumulates in the dark. Based on this, carbohydrates have historically been regarded as the primary osmotica modulating
stomatal opening. However, the discovery of an important role for potassium uptake has led to the replacement of that starch-sugar
hypothesis. Current research now focuses mainly on how K+ is transported in and out of cells when the stomata open or close. However, questions remain concerning photoreceptors, and
the functioning of guard cell chloroplasts is still disputed. Coincidentally, some recent study results have again suggested
that sucrose may play a major role in guard cell osmoregulation, thus supporting the original theory of starch-sugar involvement. 相似文献
98.
Cho YR Lee SJ Jeon HB Park ZY Chun JS Yoo YJ 《Biochemical and biophysical research communications》2004,323(3):769-775
Sulfation of proteoglycans is an important post-translational modification in chondrocytes. We previously found that 3'-phosphoadenosine 5'-phosphosulfate (PAPS) synthetase-2 levels increased more than 10-fold during mesenchymal cell chondrogenesis. Given that PAPS is the sole sulfur donor, and is produced only by PAPS synthetase in all cells, increased expression of PAPS synthetase-2 should be a prerequisite for increased sulfation activity of chondrocytes. We found that sodium chlorate, a specific inhibitor of PAPS synthetase, inhibited proteoglycan sulfation during chondrogenesis. In contrast, sodium chlorate unexpectedly induced early expression of type II collagen and increased the number of cartilage nodules during chondrogenesis. Inhibition of sulfation also accelerated the down-regulation of N-cadherin and fibronectin during chondrogenesis. These findings suggest that sulfation has an important regulatory role in coordinating the timely expression of extracellular matrix molecules during chondrogenesis, and that under-sulfation may cause the breakdown of this coordination, leading to premature chondrogenesis. 相似文献
99.
Yong Un Kang Ha Yeon Kim Joon Seok Choi Chang Seong Kim Eun Hui Bae Seong Kwon Ma Soo Wan Kim 《PloS one》2014,9(5)
Background
This study was aimed to examine the prevalence of metabolic syndrome (MS) and chronic kidney disease (CKD), and the association between MS and its components with CKD in Korea.Methods
We excluded diabetes to appreciate the real impact of MS and performed a cross-sectional study using the general health screening data of 10,253,085 (48.86±13.83 years, men 56.18%) participants (age, ≥20 years) from the Korean National Health Screening 2011. CKD was defined as dipstick proteinuria ≥1 or an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2.Results
The prevalence of CKD was 6.15% (men, 5.37%; women, 7.15%). Further, 22.25% study population had MS (abdominal obesity, 27.98%; hypertriglyceridemia, 30.09%; low high-density cholesterol levels, 19.74%; high blood pressure, 43.45%; and high fasting glucose levels, 30.44%). Multivariate-adjusted analysis indicated that proteinuria risk increased in participants with MS (odds ratio [OR] 1.884, 95% confidence interval [CI] 1.867–1.902, P<0.001). The presence of MS was associated with eGFR<60 mL/min/1.73 m2 (OR 1.364, 95% CI 1.355–1.373, P<0.001). MS individual components were also associated with an increased CKD risk. The strength of association between MS and the development of CKD increase as the number of components increased from 1 to 5. In sub-analysis by men and women, MS and its each components were a significant determinant for CKD.Conclusions
MS and its individual components can predict the risk of prevalent CKD for men and women. 相似文献100.
Seunghun Lee Won Yeong Park Hoonchul Chang Bumju Kim Won Hyuk Jang Seonghan Kim Younghoon Shin Myoung Joon Kim Kyung Hwa Lee Eui Hyun Kim Euiheon Chung Ki Hean Kim 《Journal of biophotonics》2020,13(1)
Delineation of brain tumor margins during surgery is critical to maximize tumor removal while preserving normal brain tissue to obtain optimal clinical outcomes. Although various imaging methods have been developed, they have limitations to be used in clinical practice. We developed a high‐speed cellular imaging method by using clinically compatible moxifloxacin and confocal microscopy for sensitive brain tumor detection and delineation. Moxifloxacin is a Food and Drug Administration (FDA) approved antibiotic and was used as a cell labeling agent through topical administration. Its strong fluorescence at short visible excitation wavelengths allowed video‐rate cellular imaging. Moxifloxacin‐based confocal microscopy (MBCM) was characterized in normal mouse brain specimens and visualized their cytoarchitecture clearly. Then, MBCM was applied to both brain tumor murine models and two malignant human brain tumors of glioblastoma and metastatic cancer. MBCM detected tumors in all the specimens by visualizing dense and irregular cell distributions, and tumor margins were easily delineated based on the cytoarchitecture. An image analysis method was developed for automated detection and delineation. MBCM demonstrated sensitive delineation of brain tumors through cytoarchitecture visualization and would have potentials for human applications, such as a surgery‐guiding method for tumor removal. 相似文献