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61.
Hemocytes of the last larva of the Japanese rhinoceros beetle A. dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) were classified as granulocytes, plasmatocytes, oenocytoids, spherulocytes, prohemocytes, and adipohemocytes. Among these cell types, only the granulocytes became immunologically activated with obvious morphological changes, displaying large amoeba-like, lobopodia-like, and fan-like structures. In addition, their cytoplasmic granules became larger and greatly increased in number. To explore whether these granules could be immunologically generated as phagosomes, total hemocytes were stained with LysoTracker. Greater than 90% of the granulocytes retained the LysoTracker dye at 4 h post-bacterial infection. In flow cytometry analysis, the red fluorescent signal was highly increased at 4 h post-bacterial infection (60.36%) compared to controls (5.08%), as was confirmed by fluorescent microscopy. After 12 h post-infection, these signals returned to basal levels. The uptake of pathogens by granulocytes rapidly triggered the translocation of the microtubule-associated protein 1 light chain 3 alpha (LC3) to the phagosome, which may result in enhanced pathogen killing.  相似文献   
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IL-35 subunit EBI3 is up-regulated in pulmonary fibrosis tissues. In this study, we investigated the pathological role of EBI3 in pulmonary fibrosis and dissected the underlying molecular mechanism. Bleomycin-induced pulmonary fibrosis mouse model was established, and samples were performed gene expression analyses through RNAseq, qRT-PCR and Western blot. Wild type and EBI3 knockout mice were exposed to bleomycin to investigate the pathological role of IL-35, via lung function and gene expression analyses. Primary lung epithelial cells were used to dissect the regulatory mechanism of EBI3 on STAT1/STAT4 and STAT3. IL-35 was elevated in both human and mouse with pulmonary fibrosis. EBI3 knockdown aggravated the symptoms of pulmonary fibrosis in mice. EBI3 deficiency enhanced the expressions of fibrotic and extracellular matrix-associated genes. Mechanistically, IL-35 activated STAT1 and STAT4, which in turn suppressed DNA enrichment of STAT3 and inhibited the fibrosis process. IL-35 might be one of the potential therapeutic targets for bleomycin-induced pulmonary fibrosis.  相似文献   
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The platelet microparticle proteome   总被引:4,自引:0,他引:4  
Platelet-derived microparticles are the most abundant type of microparticle in human blood and contribute to many biologically significant processes. Here, we report the first proteomic analysis of microparticles generated from activated platelets. Using 1D SDS-PAGE and liquid chromatography coupled to a linear ion trap mass spectrometer, the identification of 578 proteins was accomplished using a minimum of 5 MS/MS detections of at least two different peptides for each protein. These microparticles displayed many proteins intrinsic to and well-characterized on platelets. For example, microparticles in these experiments were found to contain membrane surface proteins including GPIIIa, GPIIb, and P-selectin, as well other platelet proteins such as the chemokines CXCL4, CXCL7, and CCL5. In addition, approximately 380 of the proteins identified were not found in two previous studies of the platelet proteome. Since several of the proteins detected here have been previously implicated in microparticle formation and/or pathological function, it is hoped that this study will help fuel future work concerning the possible role of microparticles in various disease states.  相似文献   
66.
This study was undertaken in order to demonstrate the extent to which the activity of the plasmalemma H+-ATPase compensates for the charge and acidity flow caused by the sugar-proton symport in cells of chlorella vulgaris Beij.. Detailed analysis of H+ and K+ fluxes from and into the medium together with measurements of respiration, cytoplasmic pH, and cellular ATP-levels indicate three consecutive phases after the onset of H+ symport. Phase 1 occurred immediately after addition of sugar, with an uptake of H+ by the hexoseproton symport and charge compensation by K+ loss from the cells and, to a smaller degree, by loss of another ion, probably a divalent cation. This phase coincided with strong membrane depolarization. Phase 2 started approximately 5 s after addition of sugar, when the acceleration of the H+-ATPase caused a slow-down of the K+ efflux, a decrease in the cellular ATP level and an increase in respiration. The increased respiration was most probably responsible for a pronounced net acidification of the medium. This phase was inhibited in deuterium oxide. In phase 3, finally, a slow rate of net H+ uptake and K+ loss was established for several further minutes, together with a slight depolarization of the membrane. There was hardly any pH change in the cytoplasm, because the cytoplasmic buffering capacity was high enough to stabilize the pH for several minutes despite the net H+ fluxes. The quantitative participation of the several phases of H+ and K+ flow depended on the pH of the medium, the ambient Ca2+ concentration, and the metabolic fate of the transported sugar. The results indicate that the activity of the H+-ATPase never fully compensated for H+ uptake by the sugar-symport system, because at least 10% of symport-caused charge inflow was compensated for by K+ efflux. The restoration of pH in the cytoplasm and in the medium was probably achieved by metabolic reactions connected to increased glycolysis and respiration.Abbreviations DMO dimethyloxazolidinedione - EDTA ethylcnediaminetetraacetic acid - p.c. packed cell volume  相似文献   
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A fungal mycelium is typically composed of radially extending hyphal filaments interconnected by bridges created through anastomoses. These bridges facilitate the dissemination of nutrients, water, and signaling molecules throughout the colony. In this study, we used targeted gene deletion and nitrate utilization mutants of the cruciferous pathogen Alternaria brassicicola and two closely related species to investigate hyphal fusion (anastomosis) and its role in the ability of fungi to cause disease. All eight of the A. brassicicola isolates tested, as well as A. mimicula and A. japonica, were capable of self-fusion, with two isolates of A. brassicicola being capable of non-self-fusion. Disruption of the anastomosis gene homolog (Aso1) in A. brassicicola resulted in both the loss of self-anastomosis and pathogenicity on cabbage. This finding, combined with our discovery that a previously described nonpathogenic A. brassicicola mutant defective for a mitogen-activated protein kinase gene (amk1) also lacked the capacity for self-anastomosis, suggests that self-anastomosis is associated with pathogenicity in A. brassicicola.  相似文献   
69.
IFN-kappa is a recently identified type I IFN that exhibits both structural and functional homology with the other type I IFN subclasses. In this study, we have investigated the effect of IFN-kappa on cells of the innate immune system by comparing cytokine release following treatment of human cells with either IFN-kappa or two recombinant IFN subtypes, IFN-beta and IFN-alpha2a. Although IFN-alpha2a failed to stimulate monocyte cytokine secretion, IFN-kappa, like IFN-beta, induced the release of several cytokines from both monocytes and dendritic cells, without the requirement of a costimulatory signal. IFN-kappa was particularly effective in inhibiting inducible IL-12 release from monocytes. Unlike IFN-beta, IFN-kappa did not induce release of IFN-gamma by PBL. Expression of the IFN-kappa mRNA was observed in resting dendritic cells and monocytes, and it was up-regulated by IFN-gamma stimulation in monocytes, while IFN-beta mRNA was minimally detectable under the same conditions. Monocyte and dendritic cell expression of IFN-kappa was also confirmed in vivo in chronic lesions of psoriasis vulgaris and atopic dermatitis. Finally, biosensor-based binding kinetic analysis revealed that IFN-kappa, like IFN-beta, binds strongly to heparin (K(d): 2.1 nM), suggesting that the cytokine can be retained close to the local site of production. The pattern of cytokines induced by IFN-kappa in monocytes, coupled with the unique induction of IFN-kappa mRNA by IFN-gamma, indicates a potential role for IFN-kappa in the regulation of immune cell functions.  相似文献   
70.
In plants, reactive oxygen species (ROS) are short-lived molecules produced through various cellular mechanisms in response to biotic and abiotic stimuli. ROS function as second messengers for hormone signaling, development, oxygen deprivation, programmed cell death, and plant–pathogen interactions. Recent research on ROS-mediated responses has produced stimulating findings such as the specific sources of ROS production, molecular elements that work in ROS-mediated signaling and homeostasis, and a ROS-regulated gene network (Neill et al., Curr Opin Plant Biol 5:388–395, 2002a; Apel and Hirt, Annu Rev Plant Biol 55:373–399, 2004; Mittler et al., Trends Plant Sci 9:490–498, 2004; Mori and Schroeder, Plant Physiol 135:702–708, 2004; Kwak et al., Plant Physiol 141:323–329, 2006; Torres et al., Plant Physiol 141:373–378, 2006; Miller et al., Physiol Plant 133:481–489, 2008). In this review, we highlight new discoveries in ROS-mediated abscisic acid (ABA) signaling. Drs. Daeshik Cho and June M. Kwak are the corresponding authors for this paper.  相似文献   
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