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321.
Li Zhibin Hua Zetian Dong Li Zhu Wei He Guangsheng Qu Lijun Qi Na Xu Zhengjin Wang Fang 《Journal of Plant Growth Regulation》2020,39(1):60-71
Journal of Plant Growth Regulation - RAD-seq method is a recently developed, cost-effective, and high-throughput approach for detecting genetic variability based on single-nucleotide polymorphisms... 相似文献
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Ju Wen Sun Tiantian Lu Wenyi Smith Alhaji Osman Bao Yurong Adzraku Seyram Yao Qi Kunming Xu Kailin Qiao Jianlin Zeng Lingyu 《Molecular biology reports》2020,47(4):2735-2748
Molecular Biology Reports - Murine bone marrow-derived macrophages (M0) and M1- and M2-polarized macrophages are being widely used as a laboratory model for polarized macrophages related molecular... 相似文献
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Mycopathologia - A case of fungal keratitis due to Coprinellus radians is reported. To our knowledge, fungal keratitis caused by this species was rare. Fungal hyphae were detected in corneal... 相似文献
326.
Qi Wang Monica Pujol-Canadell Maria Taveras Guy Garty Jay Perrier Carlos Bueno-Beti Igor Shuryak David J. Brenner Helen C. Turner 《Radiation and environmental biophysics》2020,59(1):89-98
Environmental contamination and ingestion of the radionuclide Cesium-137 (137Cs) is a large concern in fallout from a nuclear reactor accident or improvised nuclear device, and highlights the need to develop biological assays for low-dose rate, internal emitter radiation. To mimic low-dose rates attributable to fallout, we have developed a VAriable Dose-rate External 137Cs irradiatoR (VADER), which can provide arbitrarily varying and progressive low-dose rate irradiations in the range of 0.1–1.2 Gy/day, while circumventing the complexities of dealing with radioactively contaminated biomaterials. We investigated the kinetics of mouse peripheral leukocytes DNA damage response in vivo after variable, low-dose rate 137Cs exposure. C57BL/6 mice were placed in the VADER over 7 days with total accumulated dose up to 2.7 Gy. Peripheral blood response including the leukocyte depletion, apoptosis as well as its signal protein p53 and DNA repair biomarker γ-H2AX was measured. The results illustrated that blood leukocyte numbers had significantly dropped by day 7. P53 levels peaked at day 2 (total dose = 0.91 Gy) and then declined; whereas, γ-H2AX fluorescence intensity (MFI) and foci number generally increased with accumulated dose and peaked at day 5 (total dose = 2.08 Gy). ROC curve analysis for γ-H2AX provided a good discrimination of accumulated dose < 2 Gy and ≥ 2 Gy, highlighting the potential of γ-H2AX MFI as a biomarker for dosimetry in a protracted, environmental exposure scenario. 相似文献
327.
Mixed lineage leukemia protein (MLL1 protein) recognizes the CpG site via its CXXC domain and is frequently associated with leukemia. The specific recognition is abolished by C1188D mutation, which also prevents MLL-related leukemia. In this paper, multiple molecular dynamic (MD) simulations were performed to investigate the mechanism of recognition and influences of C1188D mutation. Started from fully dissociated DNA and MLL1-CXXC domain, remarkably, the center of mass (COM) of MLL1-CXXC domain quickly concentrates on the vicinity of the CpG site in all 53 short MD simulations. Extended simulations of the wild type showed that the native complex formed in 500 ns among 4 of 53 simulations. In contrast, the C1188D mutant COM distributed broadly around the DNA and the native complex was not observed in any of the extended simulations. Simulations on the apo MLL1-CXXC domain further suggest that the wild type protein remained predominantly in an open form that closely resembles its structure in the native complex whereas C1188D mutant formed predominantly compact structures in which the N- terminal bends to D1188. This conformational switch hinders the formation of encounter complex, thus abolishes the recognition. Our study also provides clues to the study mechanism of recognition, by the CXXC domain from proteins like DNA methyltransferase and ten-eleven translocation enzymes. 相似文献
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Lin Xin Li Liu Chuan Liu Li-Qiang Zhou Qi Zhou Yi-Wu Yuan Shi-Hao Li Hou-Ting Zhang 《Journal of cellular physiology》2020,235(3):2643-2654
Cancer stem cells are undifferentiated cancer cells that have self-renewal ability, a high tumorigenic activity, and a multilineage differentiation potential. MicroRNAs play a critical role in regulating gene expression during carcinogenesis. Here, we investigated the role of miR-7 and the mechanism by which it is dysregulated in gastric cancer stem cells (GCSCs). The stem cell marker, CD44, was used to sort GCSCs by fluorescence-activated cell sorting. We found that CD44 (+) cells have higher invasiveness and form more number of sphere colonies than CD44 (−) cells. Quantitative real-time polymerase chain reaction (PCR) revealed that the miR-7-5p expression was remarkably downregulated in GCSCs but was significantly increased in the methionine-deprived medium. The downregulation of miR-7-5p results from the increased DNA methylation in the promoter region using the methylation-specific PCR. Overexpression of miR-7-5p reduced the formation of colony and decreased the invasion of GCSCs through targeting Smo and Hes1 and subsequent repressing Notch and Hedgehog signaling pathways in vitro. Notably, upregulating miR-7-5p inhibited the growth of tumor in the xenograft model. Hence, these data demonstrated that miR-7-5p represses GCSC invasion through inhibition of Smo and Hes1, which provides a potential therapeutic target of gastric cancer treatment. 相似文献
330.
Wei Gao Chao-Qun Qi Mao-Guo Feng Peng Yang Li Liu Shu-Hong Sun 《Journal of cellular physiology》2020,235(10):6684-6696
Long noncoding RNAs (lncRNAs) have been shown to have critical regulatory roles in tumorigenesis. lncRNA LINC01561 (LINC01561) is a newly identified tumor-related lncRNA and its dysregulation has been demonstrated in several tumors. However, whether LINC01561 is involved in the progression of non-small-cell lung carcinoma (NSCLC) and its underlying mechanisms remain unknown. In this study, we first provided evidence that LINC01561 expressions were distinctly upregulated in NSCLC tissues and cell lines. Combining with bioinformatics assays and mechanism experiments, our group demonstrated that LINC01561 was activated by SOX2 in NSCLC. Clinical research revealed that upregulation of LINC01561 was related to poorer clinicopathologic features and shorter survival time. Functionally, suppression of LINC01561 exhibited tumor-suppressive functions through impairing cell proliferation, migration, and invasion as well as inducing apoptosis. Moreover, we verified that LINC01561 could directly bind to miR-760, isolating miR-760 from its target gene SHC SH2 domain-binding protein 1 (SHCBP1). We also found that SHCBP1 was lowly expressed in NSCLC and served as a tumor promoter. A functional study indicated that LINC01561 regulated SHCBP1 expression by competitively binding to miR-760. In summary, our findings indicated that SOX2-induced overexpression of LINC01561 promoted the proliferation and metastasis by acting as a competing endogenous RNA to modulate SHCBP1 by sponging miR-760. 相似文献