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861.
Jing Shen Zhangang Xiao Qijie Zhao Mingxing Li Xu Wu Lin Zhang Wei Hu Chi H. Cho 《Cell proliferation》2018,51(4)
Tumour necrosis factor alpha (TNFα) and interferon gamma (IFNγ) were originally found to be produced by inflammatory cells and play important roles in the immune system and surveillance of tumour growth. By activating distinct signalling pathways of nuclear factor‐κB (NF‐κB), mitogen‐activated protein kinase (MAPK), and JAK/STAT, TNFα and IFNγ were reported to effectively trigger cell death and perform powerful anti‐cancer effects. In this review, we will discuss the new advancements of TNFα and IFNγ in anti‐cancer therapy. 相似文献
862.
863.
Eun Jung Thak Jungho Kim Dong-Jik Lee Jeong Yoon Kim Hyun Ah Kang 《Journal of microbiology (Seoul, Korea)》2018,56(1):11-23
Protein glycosylation, the most universal and diverse post-translational modification, can affect protein secretion, stability, and immunogenicity. The structures of glycans attached to proteins are quite diverse among different organisms and even within yeast species. In yeast, protein glycosylation plays key roles in the quality control of secretory proteins, and particularly in maintaining cell wall integrity. Moreover, in pathogenic yeasts, glycans assembled on cell-surface glycoproteins can mediate their interactions with host cells. Thus, a comprehensive understanding of protein glycosylation in various yeast species and defining glycan structure characteristics can provide useful information for their biotechnological and clinical implications. Yeast-specific glycans are a target for glyco-engineering; implementing human-type glycosylation pathways in yeast can aid the production of recombinant glycoproteins with therapeutic potential. The virulenceassociated glycans of pathogenic yeasts could be exploited as novel targets for antifungal agents. Nowadays, several glycomics techniques facilitate the generation of species-and strain-specific glycome profiles and the delineation of modified glycan structures in mutant and engineered yeast cells. Here, we present the protocols employed in our laboratory to investigate the N-and O-glycan chains released from purified glycoproteins or cell wall mannoproteins in several yeast species. 相似文献
864.
Nan Kang Yu Wang Shichao Guo Yunwei Ou Guangchao Wang Jie Chen Dan Li Qimin Zhan 《BMC cell biology》2018,19(1):16
Background
TP53 gene mutations occur in more than 50% of human cancers and the vast majority of these mutations in human cancers are missense mutations, which broadly occur in DNA binding domain (DBD) (Amino acids 102–292) and mainly reside in six “hotspot” residues. TP53 G245C and R273H point mutations are two of the most frequent mutations in tumors and have been verified in several different cancers. In the previous study of the whole genome sequencing (WGS), we found some mutations of TP53 DBD in esophageal squamous cell carcinoma (ESCC) clinical samples. We focused on two high-frequent mutations TP53 p.G245C and TP53 p.R273H and investigated their oncogenic roles in ESCC cell lines, p53-defective cell lines H1299 and HCT116 p53?/?.Results
MTS and colony formation assays showed that mutant TP53 G245C and R273H increased cell vitality and proliferation. Flow cytometry results revealed inhibition of ultraviolet radiation (UV)- and ionizing radiation (IR)- induced apoptosis and disruption of TP53-mediated cell cycle arrest after UV, IR and Nocodazole treatment. Transwell assays indicated that mutant TP53 G245C and R273H enhanced cell migration and invasion abilities. Moreover, western blot revealed that they were able to suppress the expression of TP53 downstream genes in the process of apoptosis and cell cycle arrest induced by UV, which suggests that these two mutations can influence apoptosis and growth arrest might be due, at least in part, to down-regulate the expression of P21, GADD45α and PARP.Conclusions
These results indicate that mutant TP53 G245C and R273H can lead to more aggressive phenotypes and enhance cancer cell malignancy, which further uncover TP53 function in carcinogenesis and might be useful in clinical diagnosis and therapy of TP53 mutant cancers.865.
Soung-Woo Park Jin-Kee Jung Eun-A Choi Jin-Kyung Kwon Jin-Ho Kang Molly Jahn Byoung-Cheorl Kang 《Molecular breeding : new strategies in plant improvement》2014,34(3):963-975
To facilitate marker-assisted breeding and analysis of the structure and/or organization of Capsicum (pepper) genomes, this study utilized expressed sequence tags (ESTs) to develop single-nucleotide polymorphism (SNP) markers. Three different types of PCR-based markers derived from pepper ESTs were developed: intron-based polymorphic markers (IBPs), conserved ortholog sets (COSIIs), and eSNPs (EST–SNPs). For scanning and detection of SNPs, high-resolution melting analysis was performed and the resultant markers were used for linkage analysis. A total of 512 markers, comprising 214 IBP, 143 COSII, 48 eSNP, and 107 previously reported markers, were mapped on 12 linkage groups (LGs) of the “AC99” F2 population. This newly constructed interspecific map (AC2) covered 2,335.6 cM with an average marker interval distance of 4.5 cM and was aligned directly with another interspecific map (AF) for validation. Most LGs showed collinear relationships, except for the alignment of chromosomes 1 and 8 of the AC2 map to LG P1 of the AF map. Using our newly developed SNP markers, we generated chromosome-specific markers, and the previously predicted reciprocal translocation event between chromosomes 1 and 8 was revealed between wild and cultivated Capsicum by fluorescent in situ hybridization analysis. The results from this study will promote subsequent evolutionary studies of Capsicum species. 相似文献
866.
Hye Suck An Jae Kwon Cho Kyong Min Kim Maeng Hyun Son Jeong In Myeong Chul Min An 《Genes & genomics.》2014,36(5):661-669
The seven-band grouper (Epinephelus septemfasciatus) is an important fishery resource of a target for prospective aquaculture diversification and maintenance of stock quality is thus important. To explore the sustainability of fry production, genetic variations in 83 seven-band groupers from two broodstock and offspring populations of a hatchery strain were analyzed using 13 polymorphic nuclear microsatellite DNA loci; 133 alleles were identified. Allelic variability ranged from 4 to 18 in the broodstock and from 3 to 11 in the offspring. The average observed and expected heterozygosities were 0.669 and 0.734 in broodstock and 0.674 and 0.649 in offspring, respectively. Although no statistically significant reductions in heterozygosity or allelic diversity were evident in offspring, considerable loss of rare alleles was apparent. The broodstock and offspring populations exhibited significant genetic differences (F ST = 0.033, P < 0.001) indicating that genetic drift has likely promoted differentiation between the two populations, which may have negative effects on sustainable fry production. Therefore, genetic variations between broodstock and offspring should be monitored, and inbreeding should be controlled, to ensure the success of commercial breeding programs. Our data provide a useful genetic basis for future planning of sustainable culture and management of E. septemfasciatus in fisheries. 相似文献
867.
Characterization and molecular mapping of stripe rust resistance gene Yr61 in winter wheat cultivar Pindong 34 总被引:1,自引:0,他引:1
X. L. Zhou D. J. Han X. M. Chen H. L. Gou S. J. Guo L. Rong Q. L. Wang L. L. Huang Z. S. Kang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(11):2349-2358
Key message
We report a new stripe rust resistance gene on chromosome 7AS in wheat and molecular markers useful for transferring it to other wheat genotypes.Abstract
Several new races of the stripe rust pathogen have established throughout the wheat growing regions of China in recent years. These new races are virulent to most of the designated seedling resistance genes limiting the resistance sources. It is necessary to identify new genes for diversification and for pyramiding different resistance genes in order to achieve more durable resistance. We report here the identification of a new resistance gene, designated as Yr61, in Chinese wheat cultivar Pindong 34. A mapping population of 208 F2 plants and 128 derived F2:3 lines in a cross between Mingxian 169 and Pindong 34 was evaluated for seedling stripe rust response. A genetic map consisting of eight resistance gene analog polymorphism (RGAP), two sequence-tagged site (STS) and four simple sequence repeat (SSR) markers was constructed. Yr61 was located on the short arm of chromosome 7A and flanked by RGAP markers Xwgp5467 and Xwgp5765 about 1.9 and 3.9 cM in distance, which were successfully converted into STS markers STS5467 and STS5765b, respectively. The flanking STS markers could be used for marker-assisted selection of Yr61 in breeding programs. 相似文献868.
Li GQ Xia HH Chen MH Tsukamoto T Tatematsu M Gu Q Qiao L Cho CH So WH Yuen MF Hu PJ Liang YJ Lin HL Chan AO Wong BC 《Helicobacter》2008,13(1):20-29
Background: Helicobacter pylori infection is a major cause of gastritis and gastric carcinoma. Aspirin has anti‐inflammatory and antineoplastic activity. The aim of the present study was to determine the effects of aspirin on H. pylori‐induced gastritis and the development of heterotopic proliferative glands. Methods: H. pylori strain SS1 was inoculated into the stomachs of Mongolian gerbils. Two weeks after inoculation, the animals were fed with the powder diets containing 0 p.p.m. (n = 10), 150 p.p.m. (n = 10), or 500 p.p.m. (n = 10) aspirin. Mongolian gerbils were killed after 36 weeks of infection. Uninfected Mongolian gerbils (n = 10) were used as controls. Histologic changes, epithelial cell proliferation and apoptosis, and prostaglandin E2 (PGE2) levels of gastric tissue were determined. Results: H. pylori infection induced gastric inflammation. Administration of aspirin did not change H. pylori‐induced gastritis, but alleviated H. pylori‐induced hyperplasia and the development of heterotopic proliferative glands. Administration of aspirin accelerated H. pylori‐associated apoptosis but decreased H. pylori‐associated cell proliferation. In addition, the increased gastric PGE2 levels due to H. pylori infection were suppressed by treatment with aspirin, especially at the dose of 500 p.p.m. Conclusions: Aspirin alleviates H. pylori‐induced hyperplasia and the development of heterotopic proliferative glands. Moreover, aspirin increases H. pylori‐induced apoptosis. We demonstrated the antineoplastic activities of aspirin in H. pylori‐related gastric carcinogenesis. 相似文献
869.
Photosynthetic characteristics and tolerance to photo-oxidation of transgenic rice expressing C4 photosynthesis enzymes 总被引:16,自引:0,他引:16
The photosynthetic characteristics of four transgenic rice lines over-expressing rice NADP-malic enzyme (ME), and maize phosphoenolpyruvate carboxylase (PC), pyruvate,orthophosphate dikinase (PK), and PC+PK (CK) were investigated using outdoor-grown plants.
Relative to untransformed wild-type (WT) rice, PC transgenic rice exhibited high PC activity (25-fold increase) and enhanced
activity of carbonic anhydrase (more than two-fold increase), while the activity of ribulose-bisphosphate carboxylase/oxygenase
(Rubisco) and its kinetic property were not significantly altered. The PC transgenic plants also showed a higher light intensity
for saturation of photosynthesis, higher photosynthetic CO2 uptake rate and carboxylation efficiency, and slightly reduced CO2 compensation point. In addition, chlorophyll a fluorescence analysis indicates that PC transgenic plants are more tolerant to photo-oxidative stress, due to a higher capacity
to quench excess light energy via photochemical and non-photochemical means. Furthermore, PC and CK transgenic rice produced
22–24% more grains than WT plants. Taken together, these results suggest that expression of maize C4 photosynthesis enzymes in rice, a C3 plant, can improve its photosynthetic capacity with enhanced tolerance to photo-oxidation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
870.
This paper reports the results of reproduction with 45 wild African green monkeys (Cercopithecus aethiops) (36 females and 9 males) during the nine years from 1981 to 1989 under indoor individually-caged conditions. In 206 cases of menstruation observed, menstrual discharge lasted for 2.5 +/- 1.2 days in cycles of 22-48 days, and the length of each menstrual cycle was 31.2 +/- 6.5 days. Females who had regular menstrual cycles were subjected to "one-to-one timed mating"; females and males were put together on a one-to-one basis daily only for a certain period of time on and after the day of ovulation. Females who had irregular menstrual cycles or had no menstruation were subjected to "every-other-day mating"; females and males were put together on a one-to-one basis every other day for at least 16 weeks. The pregnancy rate (No. of pregnant females/No. of mated females) by one-to-one timed mating was 48.9% (116/237); 2.0 mating trials were needed to obtain one case of pregnancy. On the other hand, the pregnancy rate (No. of pregnant females/No. of mating trials) by every-other-day mating was 96% (48/50). Females who delivered normally totaled 129. The mean gestation period was 165 days when males, weighing 343 g on average at birth, were delivered, and 166 days when females, weighing 318 g on average at birth, were delivered. The male and female newborns were nursed for 131 and 138 days, respectively, on average. Details are summarized in Table 3. This paper also reports 23 cases of abortion, 6 stillbirths, and 6 cases of Caesarean section, by which three live fetuses and three dead fetuses were obtained. 相似文献