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Yuan Zhang Wei Zou Fenggong Cui Nan Wang Dongyan Zhang Yuying Cui Peng Liu Jing Liu 《The Journal of membrane biology》2014,247(1):73-80
The absorption of phospholipid may improve the fluidity of membrane and enzyme activities. Phospholipids also play a role in promoting Caveolae formation and membrane synthesis. Caveolin-1 has a significant effect on signaling pathways involved in regulating cell proliferation and stress responsiveness. Thus, we can speculate that Caveolin-1 could affect the sense of environmental stress. We use Chang liver cell line to investigate the ability of Caveolin-1 to modulate the cellular response to ethanol injury. Caveolin-1 downregulate cells (Cav-1?/?) were established by stable transfecting with psiRNA-CAV1 plasmids, which were more sensitive to toxic effects of ethanol than the untransfected parental cells (WT). Releasing of ALT and electric conductivity were changed significantly in Cav-1?/? cells compared with WT. Caveolin-1 gene silencing could obviously down-regulate the activities of protein kinase C-α (PKC-α) and phospho-p42/44 MAP kinase, indicating cell proliferation and self-repairing abilities were inhibited. However, the levels of Caveolin-1 and PKC-α were increased by phosphatidylcholine administration. The results indicated that the inhibition of lipid peroxidation by phosphatidylcholine could lead to the prevention of membrane disruption, which closely correlated with the level of Caveolin-1. Since the protective effects of phosphatidylcholine against ethanol-induced lipid peroxidation might be regulated by phospholipid-PKC-α signaling pathway, related with Caveolin-1, the potential effects of phosphatidylcholine on membranes need to be verified. 相似文献
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Xóchitl Trujillo Enrique Sánchez-Pastor Felipa Andrade Miguel Huerta 《The Journal of membrane biology》2014,247(11):1199-1205
Using polyclonal and monoclonal antibodies to visualize under a confocal microscope type-1 cannabinoid receptors (CB1) and acetylcholine (ACh) receptors, respectively, or α-bungarotoxin conjugated to Alexa-Fluor 555 for Ach receptors, we found that they colocalize on twitch muscle fibers in the frog (Rana pipiens). We show that both the CB1 and ACh receptors are present on the fast skeletal muscle motor end-plate. The CB1 receptor is present along the entire membrane of the muscle fiber, whereas the ACh receptor is expressed primarily at the motor end-plate. Analysis of the colocalization produced a cross-correlation coefficient of 0.519 ± 0.021 (n = 9) for both receptors at the muscle motor end-plate. This study suggests a close proximity between these two types of receptor proteins and that they could interact. CB1 could function at some stage of excitation–contraction coupling in these muscle fibers. However, further investigation is needed in order to clarify these issues. 相似文献
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Frugivorous and nectarivorous bats rely largely on hepatic glycogenesis and glycogenolysis for postprandial blood glucose disposal and maintenance of glucose homeostasis during short time starvation, respectively. The glycogen synthase 2 encoded by the Gys2 gene plays a critical role in liver glycogen synthesis. To test whether the Gys2 gene has undergone adaptive evolution in bats with carbohydrate-rich diets in relation to their insect-eating sister taxa, we sequenced the coding region of the Gys2 gene in a number of bat species, including three Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our results showed that the Gys2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to OWFBs and NWFBs. Our explicit convergence test showed that posterior probabilities of convergence between several branches of OWFBs, and the NWFBs were markedly higher than that of divergence. Three parallel amino acid substitutions (Q72H, K371Q, and E666D) were detected among branches of OWFBs and NWFBs. Tests for parallel evolution showed that two parallel substitutions (Q72H and E666D) were driven by natural selection, while the K371Q was more likely to be fixed randomly. Thus, our results suggested that the Gys2 gene has undergone parallel evolution on amino acid level between OWFBs and NWFBs in relation to their carbohydrate metabolism. 相似文献
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Honglei Sun Yipeng Sun Juan Pu Yi Zhang Qingyu Zhu Jing Li Jiang Gu Kin-Chow Chang Jinhua Liu 《Journal of virology》2014,88(1):725-729
Highly pathogenic avian influenza H5N1 virus clades 2.3.4, 2.3.2, and 7 are the dominant cocirculating H5N1 viruses in poultry in China. However, humans appear to be clinically susceptible mostly to the 2.3.4 virus clade. Here, we demonstrated that A549 cells and human macrophages infected with clade 2.3.4 viruses produced significantly more viruses than those infected with the other two clades. Likewise, clade 2.3.4-infected macrophages caused the most severe cellular damage and strongest proinflammatory response. 相似文献
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毛茛科类叶升麻(Actaea asiatica)有2种开花方式, 一种与同属其它植物相同, 花萼片在开花早期脱落, 花药远离柱头; 而另一种较为特殊, 能使该植物进行自花授粉, 即在花开放前, 花萼从花托上脱离, 但萼片并不张开, 部分雄蕊的花丝伸长, 将花药推入萼片和柱头之间, 收缩的花萼片将开裂的花药压在宽大的柱头上, 进而完成自花授粉。套袋实验结果表明, 类叶升麻自发自交具有很高的结籽率, 不具有孤雌生殖和风媒传粉。繁育系统估测分析结果显示, 类叶升麻自交亲和,为兼性自交的繁育系统。 相似文献
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调亏灌溉对菘蓝水分利用及产量的影响 总被引:4,自引:0,他引:4
通过探究水分调亏对河西地区膜下滴灌菘蓝(Isatis indigotica)各项生理指标、产量和水分利用的影响,为菘蓝高效节水种植提供理论指导。于2016年在河西走廊中部张掖市民乐县益民灌溉试验站进行菘蓝水分调亏研究,在保持苗期和肉质根成熟期充分灌溉的情况下,在菘蓝营养生长期和肉质根生长期分别进行轻度、中度和重度的水分亏缺处理,并测定各项光合生理指标、产量和水分利用率。结果表明,营养生长期和肉质根生长期的中度与重度水分亏缺显著降低了菘蓝叶片净光合速率、叶面积指数、株高及主根长,并且随水分亏缺程度加重降幅增大;而轻度水分亏缺与对照组的差异不显著。营养生长期和肉质根生长期轻度水分亏缺处理的菘蓝产量与水分利用效率最高,分别达到8 239.56 kg·hm~(–2)和24.11kg·hm~(–2)·mm~(–1);其它水分亏缺处理组产量和水分利用效率均有所降低,与对照组之间差异显著(P0.05),重度水分亏缺处理各项指标均最低。因此,最优的菘蓝水分调控处理为营养生长期和肉质根生长期的轻度水分调亏,能够降低菘蓝耗水量,提高水分利用效率且其产量不会降低。 相似文献