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91.
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93.
探讨信号转导和转录激活子5(STAT5)信号转导途径在受辐射KG-1细胞中对细胞周期的调控作用。通过转染STAT5基因的显性负突变体(DN-STAT5)阻断JAK/STAT的信号传递后,瞬间转染cyclinD1基因及cyclinB1基因,观察cyclinD1蛋白及cyclinB1蛋白对受辐射细胞周期阻滞的影响作用。转染DN-STSAT5基因的受辐射KG-1细胞即使用粒-巨噬细胞集落刺激因子(GM-CSF)刺激亦不能跳出G1期阻滞;瞬间转染cyclinD1基因及cyclinB1基因分别能促进受辐射细胞跳出G1期和G2期阻滞。GM-CS所激活的JAK/STAT信号转导途径通过促进周期蛋白cyclinD1及cyclinB1的表达而对受辐射细胞周期进行调控。 相似文献
94.
针对现有服装销售管理的现状及信息化需求,研究了基于B/S结构的服装销售管理系统,并利用asp加以实现。通过三层结构实现了系统的原型设计,介绍了基于B/S结构的服装销售管理系统的体系结构、功能及系统实现的关键技术。 相似文献
95.
数字温度测量模块LTM8003及其应用 总被引:3,自引:0,他引:3
LTM8003是一种新型数字温度传感器模块,该模块具有管理512个数字温度传感器的能力,它可利用其自身的RS-485口来和上位机一起构成数字多点测温网络系统,可广泛应用于粮食、档案库等行业的温度监测系统中,文中介绍了该模块的特点、命令集及典型应用。 相似文献
96.
97.
Miriam Baeumers Katharina Schulz Thomas Klein 《International journal of molecular sciences》2022,23(14)
The evolutionary conserved ESCRT-III complex is a device for membrane remodelling in various cellular processes, such as the formation of intraluminal vesicles (ILVs), cytokinesis, and membrane repair. The common theme of all these processes is the abscission of membrane away from the cytosol. At its heart in Drosophila is Shrub, CHMP4 in humans, which dynamically polymerises into filaments through electrostatic interactions among the protomers. For the full activity, Shrub/CHMP4 requires physical interaction with members of the Lgd protein family. This interaction is mediated by the odd-numbered DM14 domains of Lgd, which bind to the negative interaction surface of Shrub. While only one Lgd and one Shrub exist in the genome of Drosophila, mammals have two Lgd orthologs, LGD1/CC2D1B and LGD2/CC2D1A, as well as three CHMP4s in their genomes, CHMP4A, CHMP4B, and CHMP4C. The rationale for the diversification of the ESCRT components is not understood. We here use Drosophila as a model system to analyse the activity of the human orthologs of Shrub and Lgd at an organismal level. This enabled us to use the plethora of available techniques available for Drosophila. We present evidence that CHMP4B is the true ortholog of Shrub, while CHMP4A and CHMP4C have diverging activities. Nevertheless, CHMP4A and CHMP4C can enhance the activity of CHMP4B, raising the possibility that they can form heteropolymers in vivo. Our structure-function analysis of the LGD1 and LGD2 indicates that the C2 domain of the LGD proteins has a specific function beyond protein stability and subcellular localisation. Moreover, our data specify that CHMP4B interacts more efficiently with LGD1 than with LGD2. 相似文献
98.
Britta Marko Paulina Heurich Patrick Thon Frieda Zimmer Lars Bergmann Hartmuth Nowak Katharina Rump Bjrn Koos Michael Adamzik Matthias Unterberg Tim Rahmel 《International journal of molecular sciences》2022,23(14)
The functionally important NF-κB1 promoter polymorphism (−94ins/delATTG) significantly shapes inflammation and impacts the outcome of sepsis. However, exploratory studies elucidating the molecular link of this genotype-dependent pattern are lacking. Accordingly, we analyzed lipopolysaccharide-stimulated peripheral blood mononuclear cells from both healthy volunteers (n = 20) and septic patients (n = 10). All individuals were genotyped for the −94ins/delATTG NF-κB1 promoter polymorphism. We found a diminished nuclear activity of the NF-κB subunit p50 in ID/DD genotypes after 48 h of lipopolysaccharide stimulation compared to II genotypes (p = 0.025). This was associated with higher TNF-α (p = 0.005) and interleukin 6 concentrations (p = 0.014) and an increased production of mitochondrial radical oxygen species in ID/DD genotypes (p = 0.001). Although ID/DD genotypes showed enhanced activation of mitochondrial biogenesis, they still had a significantly diminished cellular ATP content (p = 0.046) and lower mtDNA copy numbers (p = 0.010) compared to II genotypes. Strikingly, these findings were mirrored in peripheral blood mononuclear cells taken from septic patients. Our results emphasize the crucial aspect of considering NF-κB subunits in sepsis. We showed here that the deletion allele of the NF-κB1 (−94ins/delATTG) polymorphism was associated with the lower nuclear activity of subunit p50, which, in turn, was associated with aggravated inflammation and mitochondrial dysfunction. 相似文献
99.
Weizeng Lv Xue He Haojuan Guo Haibin Lan Yanqing Jiao Le Li Yanhao Lian Zhiqiang Wang Zeyu Xin Yongzhe Ren Tongbao Lin 《International journal of molecular sciences》2022,23(14)
Excessive input of nitrogen fertilizer not only causes a great waste of resources but brings about a series of ecological and environmental problems. Although Small Auxin Up-regulated RNAs (SAURs) participate in diverse biological processes, the function of SAURs in the nitrogen starvation response has not been well-studied. Here, we identified 308 TaSAURs in wheat and divided them into 10 subfamilies. The promoter regions of most TaSAURs contain hormone responsive elements, and their expression levels change under the treatment of different hormones, such as IAA, MeJA, and ABA. Interestingly, overexpression of one of the TaSAUR family members, a nitrogen starvation responsive gene, TaSAUR66-5B, can promote the growth of Arabidopsis and wheat roots. In addition, overexpression of TaSAUR66-5B in Arabidopsis up-regulates the expression levels of auxin biosynthesis related genes, suggesting that overexpression TaSAUR66-5B may promote root growth by increasing the biosynthesis of auxin. Furthermore, overexpression of TaSAUR66-5B in wheat can increase the biomass and grain yields of transgenic plants, as well as the nitrogen concentration and accumulation of both shoots and grains, especially under low nitrogen conditions. This study provides important genomic information of the TaSAUR gene family and lays a foundation for elucidating the functions of TaSAURs in improving nitrogen utilization efficiency in wheat. 相似文献
100.
Kim Ghilarducci Valrie C. Cabana Ali Harake Laurent Cappadocia Marc P. Lussier 《International journal of molecular sciences》2022,23(14)
Rab7 is a GTPase that controls late endosome and lysosome trafficking. Recent studies have demonstrated that Rab7 is ubiquitinated, a post-translational modification mediated by an enzymatic cascade. To date, only one ubiquitin E3 ligase and one deubiquitinase have been identified in regulating Rab7 ubiquitination. Here, we report that RNF167, a transmembrane endolysosomal ubiquitin ligase, can ubiquitinate Rab7. Using immunoprecipitation and in vitro ubiquitination assays, we demonstrate that Rab7 is a direct substrate of RNF167. Subcellular fractionation indicates that RNF167 activity maintains Rab7′s membrane localization. Epifluorescence microscopy in HeLa cells shows that Rab7-positive vesicles are larger under conditions enabling Rab7 ubiquitination by RNF167. Characterization of its ubiquitination reveals that Rab7 must be in its GTP-bound active form for membrane anchoring and, thus, accessible for RNF167-mediated ubiquitin attachment. Cellular distribution analyses of lysosome marker Lamp1 show that vesicle positioning is independent of Rab7 and RNF167 expression and that Rab7 endosomal localization is not affected by RNF167 knockdown. However, both Rab7 and RNF167 depletion affect each other’s lysosomal localization. Finally, this study demonstrates that the RNF167-mediated ubiquitination of Rab7 GTPase is impaired by variants of Charcot–Marie–Tooth Type 2B disease. This study identified RNF167 as a new ubiquitin ligase for Rab7 while expanding our knowledge of the mechanisms underlying the ubiquitination of Rab7. 相似文献