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91.
As a newly discovered E3 ubiquitin ligase, ZNRF1 protein participates in controlling Wallerian degeneration, but the role in cancer biology has been seldom reported. We analyzed the change of proliferation, apoptosis, stemness and protein levels of AKT and STAT5 after leukemia NB4 cells were treated with ZNRF1 siRNA and with expression vector. The results showed that over-expression of ZNRF1 inhibited proliferation and increased apoptosis of NB4 cells, but ZNRF1 siRNA did not influence the proliferation and apoptosis. Over-expression of ZNRF1 diminished cancer stem cell properties and down-regulated AKT and STAT5. This is the first study to show that ZNRF1 inhibited proliferation and stemness properties of leukemia NB4 cells possibly through AKT signal and STAT5 signal. 相似文献
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Xueyin Qi Shuai Zhou Xiaoguang Shang Xinyu Wang 《Journal of Phytopathology》2016,164(11-12):1064-1074
Verticillium dahliae infection leads to Verticillium wilt in cotton and other dicotyledon crops. To reduce the loss of economic crops, more attention has been focused on the key genes involved in pathogenicity of this soil‐borne plant fungal pathogen. Sho1 encodes a conserved tetraspan transmembrane protein which is a key element of the two upstream branches of the HOG‐MAPK pathway in fungi. Sho1 is required for full virulence in a wide variety of pathogenic fungi. In this study, sho1 mutant in V. dahliae (designated ΔVdsho1) was generated by Agrobacterium tumefaciens‐mediated transformation. ΔVdsho1 strain was highly sensitive to menadione (at concentration of 120 μm ) and hydrogen peroxide (at concentration of 250 μm ), displayed delayed spore germination and reduced spore production compared with the wild type and the complemented strains. During infection of host cotton plants, ΔVdsho1 exhibited impaired ability of root attachment and invasive growth. Results from the present work suggest that VdSho1 controls external sensing, virulence and multiple growth‐related traits in V. dahliae and might serve as a potential target for control of Verticillium wilt. 相似文献
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Hongrui Sun Jing Zhang Xinlei Gan Luting Yu Haobo Yuan Minghui Shang Chaojie Lu Dagang Hou Ziyang Hu Yuejin Zhu Liyuan Han 《Liver Transplantation》2019,9(25)
Fabrication of efficient Pb reduced inorganic CsPbI2Br perovskite solar cells (PSC) are an important part of environment‐friendly perovskite technology. In this work, 10% Pb reduction in CsPb0.9Zn0.1I2Br promotes the efficiency of PSCs to 13.6% (AM1.5, 1sun), much higher than the 11.8% of the pure CsPbI2Br solar cell. Zn2+ has stronger interaction with the anions to manipulate crystal growth, resulting in size‐enlarged crystallite with enhanced growth orientation. Moreover, the grain boundaries (GBs) are passivated by the Cs‐Zn‐I/Br compound. The high quality CsPb0.9Zn0.1I2Br greatly diminishes the GB trap states and facilitates the charge transport. Furthermore, the Zn4s‐I5p states slightly reduce the energy bandgap, accounting for the wider solar spectrum absorption. Both the crystalline morphology and energy state change benefit the device performance. This work highlights a nontoxic and stable Pb reduction method to achieve efficient inorganic PSCs. 相似文献
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Ting Wang Yanjun Li Juan Li Dezhi Zhang Ningyun Cai Guihong Zhao Hongkun Ma Can Shang Qian Ma Qingyang Xu Ning Chen 《Microbial biotechnology》2019,12(5):907-919
Corynebacterium glutamicum is an important industrial microorganism, but the availability of tools for its genetic modification has lagged compared to other model microorganisms such as Escherichia coli. Despite great progress in CRISPR-based technologies, the most feasible genome editing method in C. glutamicum is suicide plasmid-mediated, the editing efficiency of which is low due to high false-positive rates of sacB counter selection, and the requirement for tedious two-round selection and verification of rare double-cross-over events. In this study, an rpsL mutant conferring streptomycin resistance was harnessed for counter selection, significantly increasing the positive selection rate. More importantly, with the aid of high selection efficiencies through the use of antibiotics, namely kanamycin and streptomycin, the two-step verification strategy can be simplified to just one-step verification of the final edited strain. As proof of concept, a 2.5-kb DNA fragment comprising aroGfbrpheAfbr expressing cassettes was integrated into the genome of C. glutamicum, with an efficiency of 20% out of the theoretical 50%. The resulting strain produced 110 mg l−1 l -tyrosine in shake-flask fermentation. This updated suicide plasmid-mediated genome editing system will greatly facilitate genetic manipulations including single nucleotide mutation, gene deletion and gene insertion in C. glutamicum and can be easily applied to other microbes. 相似文献
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