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991.
Objectives: Epstein-Barr virus (EBV) transformation has been described as a routine method to establish human B lymphoblastoid cell lines. Each established lymphoblastoid cell line represents one unique genetic information carrier and can produce unlimited quantities of DNA materials available for downstream applications and research. Undoubtedly, it is of great value to human clinical and experimental genetic studies. However, the current process of EBV transformation requires much manpower in the routine renewal of medium, which is time-consuming. This situation can become a serious problem especially when establishing a human B lymphoblastoid cell bank. A modified and cost-effective protocol for EBV transformation should be considered.
Materials and methods: In the present study, process in EBV transformation was modified to fit the requirements of robot handling.
Results: 1 mL of whole blood was demonstrated to be sufficient to perform EBV transformation. Additionally, EBV transformation can performed in 96-deep-well plates that are directly and widely used with automatic work platforms.
Conclusions: Based on these facts, a process of EBV transformation can be modified to fit the requirements of robot handling. 相似文献
Materials and methods: In the present study, process in EBV transformation was modified to fit the requirements of robot handling.
Results: 1 mL of whole blood was demonstrated to be sufficient to perform EBV transformation. Additionally, EBV transformation can performed in 96-deep-well plates that are directly and widely used with automatic work platforms.
Conclusions: Based on these facts, a process of EBV transformation can be modified to fit the requirements of robot handling. 相似文献
992.
Hyung Keun Oh Hyung Joo Yoon Min Jee Kim Hyung Uk Jeong Seong Ryul Kim Jae Sam Hwang Chang Hwan Bae Iksoo Kim 《Genes & genomics.》2009,31(4):293-303
The bumblebee species,Bombus, is an invaluable natural resource for greenhouse pollination. Low levels of genetic variation ofBombus ardens have been reported in a previous mitochondrial (mt) gene study. In this study, we sequenced the complete internal transcribed spacer 2 (ITS2) of the nuclear rDNA obtained from 100B. ardens individuals collected from several Korean localities, in an effort to assess its usefulness in characterizing the genetic diversity and relationships among populations of B. ardens. The ITS2 sequences ofB. ardens were shown to be longest among known insects, ranging in size from 1,971–1,984 bp. The sequences harbor four duplicated repeats-≈27 bp repeats, ≈20 bp repeats, ≈33 bp repeats, and ≈34 bp repeats-which have never before been reported in other insect ITS2 rDNA. The maximum sequence divergence of 1.01% among 96 sequence types confirmed the applicability of this molecule to the study of intraspecific variation, revealing higher sequence variation as compared to the previously studied mt COI gene. Overall, a very high per generation migration ratio (Nm = 5.83 ≈ infinite) and a very low level of genetic fixation (FST =0 –0.08) were noted to exist among populations ofB. ardens. The high estimation of gene flow among most populations-in particular, between the remote island Ulleungdo and several inland populations-suggest that historical events may be more responsible for the contemporary population structure of B. ardens. The finding of the lowest genetic diversity (π) in the population on Ulleungdo Island (π = 0.007434) may be reflective of a relatively small population size and the geographical isolation of the population as compared with other inland populations. 相似文献
993.
Han Song Junghyun Hwang Jaehee Myung Hyoseok Seo Hyojeong Yi Hee-Sun Sim Bong-Su Kim William C. Nierman Heenam Stanley Kim 《Molecules and cells》2009,27(2):237-241
Pathogens Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm) contain a large number (> 12,000) of Simple Sequence Repeats (SSRs). To study the extent to which these features have
contributed to the diversification of genes, we have conducted comparative studies with nineteen genomes of these bacteria.
We found 210 genes with characteristic types of SSR variations. SSRs with nonamer repeat units were the most abundant, followed
by hexamers and trimers. Amino acids with smaller and nonpolar R-groups are preferred to be encoded by the variant SSRs, perhaps
due to their minimal impacts to protein functionality. A majority of these genes appears to code for surface or secreted proteins
that may directly interact with the host factors during pathogenesis or other environmental factors. There also are others
that encode diverse functions in the cytoplasm, and this protein variability may reflect an extensive involvement of phase
variation in survival and adaptation of these pathogens. 相似文献
994.
JeeNa Hwang Jinjie Li Wing-Yee Liu Song-Ji An Hwajin Cho Nam Han Her Inhwa Yeam Dosun Kim Byoung-Cheorl Kang 《Molecules and cells》2009,27(3):329-336
To evaluate the involvement of translation initiation factors eIF4E and eIFiso4E in Chilli veinai mottle virus (ChiVMV) infection in pepper, we conducted a genetic analysis using a segregating population derived from a cross between
Capsicum annuum ‘Dempsey’ containing an eIF4E mutation (pvr1
2
) and C. annuum ‘Perennial’ containing an eIFiso4E mutation (pvr6). C. annuum ‘Dempsey’ was susceptible and C. annuum ‘Perennial’ was resistant to ChiVMV. All F1 plants showed resistance, and F2 individuals segregated in a resistant-susceptible ratio of 166:21, indicating that many resistance loci were involved. Seventy-five
F2 and 329 F3 plants of 17 families were genotyped with pvr1
2
and pvr6 allele-specific markers, and the genotype data were compared with observed resistance to viral infection. All plants containing
homozygous genotypes of both pvr1
2
and pvr6 were resistant to ChiVMV, demonstrating that simultaneous mutations in eIF4E and eIFiso4E confer resistance to ChiVMV in pepper. Genotype analysis of F2 plants revealed that all plants containing homozygous genotypes of both pvr1
2
and pvr6 showed resistance to ChiVMV. In protein-protein interaction experiments, ChiVMV viral genome-linked protein (VPg) interacted
with both eIF4E and eIFiso4E. Silencing of eIF4E and eIFiso4E in the VIGS experiment showed reduction in ChiVMV accumulation. These results demonstrated that ChiVMV can use both eIF4E
and eIFiso4E for replication, making simultaneous mutations in eIF4E and eIFiso4E necessary to prevent ChiVMV infection in pepper.
These authors contributed equally to this work. 相似文献
995.
Juneyoung Lee Hyun Joo Hong Jin-Kyoung Kim Jae-Sam Hwang Yangmee Kim Dong Gun Lee 《Molecules and cells》2009,28(5):473-477
Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated
from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited
that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides
and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner.
As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled
giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active
mechanism of 9Pbw4 could have originated from the poreforming action and the radii of pores was presumed to be anywhere from
1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential
of 9Pbw4 as a novel antifungal peptide. 相似文献
996.
Jae-Jun Kee Sang Eun Jun Seung-A Baek Tae-Soo Lee Myung Rae Cho Hyun-Sik Hwang Suk-Chan Lee Jongkee Kim Gyung-Tae Kim Kyung-Hoan Im 《Molecules and cells》2009,28(2):93-98
A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology. 相似文献
997.
The promoter of the pepper pathogen-induced membrane protein gene CaPIMP1 was analyzed by an Agrobacterium-mediated transient expression assay in tobacco leaves. Several stress-related cis-acting elements (GT-1, W-box and ABRE) are located within the CaPIMP1 promoter. In tobacco leaf tissues transiently transformed with a CaPIMP1 promoter-β-glucuronidase (GUS) gene fusion, serially 5′-deleted CaPIMP1 promoters were differentially activated by Pseudomonas syringae pv. tabaci, ethylene, methyl jasmonate, abscisic acid, and nitric oxide. The −1,193 bp region of the CaPIMP1 gene promoter sequence exhibited full promoter activity. The −417- and −593 bp promoter regions were sufficient for GUS gene activation by ethylene and methyl jasmonate treatments, respectively. However, CaPIMP1 promoter sequences longer than −793 bp were required for promoter activation by abscisic acid and sodium nitroprusside treatments.
CaPIMP1 expression was activated in pepper leaves by treatment with ethylene, methyl jasmonate, abscisic acid, β-amino-n-butyric acid, NaCl, mechanical wounding, and low temperature, but not with salicylic acid. Overexpression of CaPIMP1 in Arabidopsis conferred hypersensitivity to mannitol, NaCl, and ABA during seed germination but not during seedling development. In contrast,
transgenic plants overexpressing CaPIMP1 exhibited enhanced tolerance to oxidative stress induced by methyl viologen during germination and early seedling stages.
These results suggest that CaPIMP1 expression may alter responsiveness to environmental stress, as well as to pathogen infection.
The nucleotide sequence data reported here has been deposited in the GenBank database under the accession number DQ356279. 相似文献
998.
999.
1000.
Investigating the adaptive model of thermal comfort for naturally ventilated school buildings in Taiwan 总被引:1,自引:0,他引:1
Ruey-Lung Hwang Tzu-Ping Lin Chen-Peng Chen Nai-Jung Kuo 《International journal of biometeorology》2009,53(2):189-200
Divergence in the acceptability to people in different regions of naturally ventilated thermal environments raises a concern
over the extent to which the ASHRAE Standard 55 may be applied as a universal criterion of thermal comfort. In this study,
the ASHRAE 55 adaptive model of thermal comfort was investigated for its applicability to a hot and humid climate through
a long-term field survey performed in central Taiwan among local students attending 14 elementary and high schools during
September to January. Adaptive behaviors, thermal neutrality, and thermal comfort zones are explored. A probit analysis of
thermal acceptability responses from students was performed in place of the conventional linear regression of thermal sensation
votes against operative temperature to investigate the limits of comfort zones for 90% and 80% acceptability; the corresponding
comfort zones were found to occur at 20.1–28.4°C and 17.6–30.0°C, respectively. In comparison with the yearly comfort zones
recommended by the adaptive model for naturally ventilated spaces in the ASHRAE Standard 55, those observed in this study
differ in the lower limit for 80% acceptability, with the observed level being 1.7°C lower than the ASHRAE-recommended value.
These findings can be generalized to the population of school children, thus providing information that can supplement ASHRAE
Standard 55 in evaluating the thermal performance of naturally ventilated school buildings, particularly in hot-humid areas
such as Taiwan. 相似文献