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81.
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FERONIA receptor kinase interacts with S‐adenosylmethionine synthetase and suppresses S‐adenosylmethionine production and ethylene biosynthesis in Arabidopsis
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Dandan Mao Feng Yu Jian Li Bram Van de poel Dan Tan Jianglin Li Yanqionq Liu Xiushang Li Mengqiu Dong Liangbi Chen Dongping Li Sheng Luan 《Plant, cell & environment》2015,38(12):2566-2574
Environmental inputs such as stress can modulate plant cell metabolism, but the detailed mechanism remains unclear. We report here that FERONIA (FER), a plasma membrane receptor‐like kinase, may negatively regulate the S‐adenosylmethionine (SAM) synthesis by interacting with two S‐adenosylmethionine synthases (SAM1 and SAM2). SAM participates in ethylene, nicotianamine and polyamine biosynthetic pathways and provides the methyl group for protein and DNA methylation reactions. The Arabidopsis fer mutants contained a higher level of SAM and ethylene in plant tissues and displayed a dwarf phenotype. Such phenotype in the fer mutants was mimicked by over‐expressing the S‐adenosylmethionine synthetase in transgenic plants, whereas sam1/2 double mutant showed an opposite phenotype. We propose that FER receptor kinase, in response to environmental stress and plant hormones such as auxin and BR, interacts with SAM synthases and down‐regulates ethylene biosynthesis. 相似文献
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Li Y Tan C Gao C Zhang C Luan X Chen X Liu H Chen Y Jiang Y 《Bioorganic & medicinal chemistry》2011,19(15):4529-4535
Multi-target EGFR, VEGFR-2 and PDGFR inhibitors are highly useful anticancer agents with improved therapeutic efficacies. In this work, we used two virtual screening methods, support vector machines (SVM) and molecular docking, to identify a novel series of benzimidazole derivatives, 2-aryl benzimidazole compounds, as multi-target EGFR, VEGFR-2 and PDGFR inhibitors. 2-Aryl benzimidazole compounds were synthesized and their biological activities against a tumor cell line HepG-2 and specific kinases were evaluated. Among these compounds, compounds 5a and 5e exhibited high cytotoxicity against HepG-2 cells with IC?? values at ~2 μM. Further kinase assay study showed that compound 5a have good EGFR inhibitory activity and moderate VEGFR-2 and PDGFR inhibitory activities, while 5e have moderate EGFR inhibitory activity and slightly weaker VEGFR-2 and PDGFR inhibitory activities. Molecular docking analysis suggested that compound 5a more tightly interacts with EGFR and PDGFR than compound 5e. Our study discovered a novel series of benzimidazole derivatives as multi-target EGFR, VEGFR-2 and PDGFR kinases inhibitors. 相似文献
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Li Yu Dan Peng Jiang Liu Pengtao Luan Lu Liang Hang Lee Muyeong Lee Oliver A Ryder Yaping Zhang 《BMC evolutionary biology》2011,11(1):92
Background
Mustelidae, as the largest and most-diverse family of order Carnivora, comprises eight subfamilies. Phylogenetic relationships among these Mustelidae subfamilies remain argumentative subjects in recent years. One of the main reasons is that the mustelids represent a typical example of rapid evolutionary radiation and recent speciation event. Prior investigation has been concentrated on the application of different mitochondrial (mt) sequence and nuclear protein-coding data, herein we employ 17 nuclear non-coding loci (>15 kb), in conjunction with mt complete genome data (>16 kb), to clarify these enigmatic problems. 相似文献88.
89.
Background
The dorsal raphe nucleus (DRN) of the mesencephalon is a complex multi-functional and multi-transmitter nucleus involved in a wide range of behavioral and physiological processes. The DRN receives a direct input from the retina. However little is known regarding the type of retinal ganglion cell (RGC) that innervates the DRN. We examined morphological characteristics and physiological properties of these DRN projecting ganglion cells.Methodology/Principal Findings
The Mongolian gerbils are highly visual rodents with a diurnal/crepuscular activity rhythm. It has been widely used as experimental animals of various studies including seasonal affective disorders and depression. Young adult gerbils were used in the present study. DRN-projecting RGCs were identified following retrograde tracer injection into the DRN, characterized physiologically by extracellular recording and morphologically after intracellular filling. The result shows that DRN-projecting RGCs exhibit morphological characteristics typical of alpha RGCs and physiological response properties of Y-cells. Melanopsin was not detected in these RGCs and they show no evidence of intrinsic photosensitivity.Conclusions/Significance
These findings suggest that RGCs with alpha-like morphology and Y-like physiology appear to perform a non-imaging forming function and thus may participate in the modulation of DRN activity which includes regulation of sleep and mood. 相似文献90.
Véronique Vincourt Luan Nguyen Jean-Claude Chaumeil Gilles Dumortier 《Cryobiology》2010,60(3):262-270
Concerning the instability of ATP liposomes formulated to easily diffuse through the liver (size ~100 nm), this work targets the key parameters that influence the freeze-drying of a preparation that combines cholesterol, DOTAP and phosphatidylcholine (either natural soybean or egg (SPC or EPC) or hydrogenated (HSPC)). After freeze-drying blank liposomes, size increased significantly when initial lipid concentration was lowered from 20 to 5 mM (p = 0.0018). With low lipid concentration preparation (5 mM), SPC limited size increase (SI) more efficiently compared to EPC or HSPC. With SPC and EPC, sucrose showed better size results compared to trehalose (Lyoprotectant/Lipid ratio (w/w) avoiding any SI: ~5 and ~10 (for SPC), ~10 and ~15 (for EPC), for sucrose and trehalose, respectively), but the opposite was evidenced with HSPC liposomes where a Trehalose/Lipid ratio of 25 barely prevented SI. In addition, slow versus quick cooling rate led to limiting SI for HSPC liposomes (p = 0.0035). With sucrose or trehalose at both Lyoprotectant/Lipid ratios ensuring size stabilisation (10:1 and 15:1, respectively), ATP leakage ranged between 38.8 ± 7.9% and 58.2 ± 1.4%. In conclusion, this study emphasizes that using strict size maintenance as the primary objective does not result in drug complete retention inside the liposome core. 相似文献