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111.
112.
Julie Tan 《Critical reviews in biochemistry and molecular biology》2014,49(1):33-58
AbstractPhosphatidylinositol lipids are signaling molecules involved in nearly all aspects of cellular regulation. Production of phosphatidylinositol 4-phosphate (PI4P) has long been recognized as one of the first steps in generating poly-phosphatidylinositol phosphates involved in actin organization, cell migration, and signal transduction. In addition, progress over the last decade has brought to light independent roles for PI4P in membrane trafficking and lipid homeostasis. Here, we describe recent advances that reveal the breadth of processes regulated by PI4P, the spectrum of PI4P effectors, and the mechanisms of spatiotemporal control that coordinate crosstalk between PI4P and cellular signaling pathways. 相似文献
113.
Weicheng Zhao Shaoli Zhou Weifeng Yao Xiaoliang Gan Guangjie Su Dongdong Yuan Ziqing Hei 《Life sciences》2014
Aims
Both mast cells and oxidative stress are involved in acute lung injury (ALI) induced by intestinal ischemia–reperfusion (IIR). The aim of this study was to investigate whether propofol could improve IIR-induced ALI through inhibiting their interaction.Main methods
Repetitive, brief IIR or IIR + compound 48/80 was performed in adult Sprague–Dawley rats pretreated with saline, apocynin or propofol. And their lungs were excised for histology, ELISA and protein-expression measurements 2 h after reperfusion.Key findings
Rats pretreated with saline developed critical ALI 2 h after IIR. We found significant elevations in lung injury scores, lung wet/dry ratio and gp91phox, p47phox, intercellular cell adhesion molecule-1 protein expressions and higher level of malondialdehyde, interleukin-6 contents, and myeloperoxidase activities, as well as significant reductions in superoxide dismutase activities, accompanied with increases in mast cell degranulation evidenced by significant increases in mast cell counts, β-hexosaminidase concentrations, and tryptase expression. And the lung injury was aggravated in the presence of compound 48/80. However, pretreated with propofol and apocynin not only ameliorated the IIR-mediated pulmonary changes beyond the biochemical changes but also reversed the changes that were aggravated by compound 48/80.Significance
Propofol protects against IIR-mediated ALI, most likely by inhibiting the interaction between oxidative stress and mast cell degranulation. 相似文献114.
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117.
Phosphorylation of Pkp1 by RIPK4 regulates epidermal differentiation and skin tumorigenesis 下载免费PDF全文
Philbert Lee Shangwen Jiang Yuanyuan Li Jiping Yue Xuewen Gou Shao‐Yu Chen Yingming Zhao Markus Schober Minjia Tan Xiaoyang Wu 《The EMBO journal》2017,36(13):1963-1980
Tissue homeostasis of skin is sustained by epidermal progenitor cells localized within the basal layer of the skin epithelium. Post‐translational modification of the proteome, such as protein phosphorylation, plays a fundamental role in the regulation of stemness and differentiation of somatic stem cells. However, it remains unclear how phosphoproteomic changes occur and contribute to epidermal differentiation. In this study, we survey the epidermal cell differentiation in a systematic manner by combining quantitative phosphoproteomics with mammalian kinome cDNA library screen. This approach identified a key signaling event, phosphorylation of a desmosome component, PKP1 (plakophilin‐1) by RIPK4 (receptor‐interacting serine–threonine kinase 4) during epidermal differentiation. With genome‐editing and mouse genetics approach, we show that loss of function of either Pkp1 or Ripk4 impairs skin differentiation and enhances epidermal carcinogenesis in vivo. Phosphorylation of PKP1's N‐terminal domain by RIPK4 is essential for their role in epidermal differentiation. Taken together, our study presents a global view of phosphoproteomic changes that occur during epidermal differentiation, and identifies RIPK‐PKP1 signaling as novel axis involved in skin stratification and tumorigenesis. 相似文献
118.
In this paper, photosynthetic characteristics of green leaves (GL) and green pseudobulbs (GPSB) of C3 orchid Oncidium Golden Wish were first studied. Light saturation for photosynthesis and maximum photosynthetic rates (P
max) were significantly higher in GL than in GPSB. The results of the optimal PSII quantum yield (Fv/Fm ratio), electron transport rate (ETR), the effective photochemical quantum yield (ΔF/Fm′) and nonphotochemical quenching (NPQ) of Chl fluorescence revealed that GPSB had lower light utilization than that of GL.
Significantly higher photosynthetic pigments were found in GL than in GPSB. Alteration of source/sink ratio had no impact
on all photosynthetic parameters for both GL and GPSB after a short term of 3 days or even a long term of 2 weeks of treatments
although there were significant decreases in GL carbohydrate concentration of GL-darkened plants by the end of the day. However,
decreases of all photosynthetic parameters of GL were observed in GL-darkened plants after 4 weeks of treatment compared to
those of fully illuminated (FI) and GPSB-darkened plants. These results indicate that the level of carbohydrates in GL plays
an important role in regulating their photosynthesis. Due to their lower photosynthetic capacities, GPSB function mainly as
sinks. Darkening GPSB up to 2 weeks did not affect their own P
max and the P
max of GL and thus, did not result in significant decreases of total carbohydrate concentration of GPSB. As GPSB store a large
amount of carbohydrates, it could also act as a source when the level of carbohydrates decreased. Thus, GL could depend on
GPSB carbohydrates to regulate their photosynthesis when their source capacity was removed. However, 4 weeks after treatments,
photosynthetic capacities of GL were significantly lower in GL- and GPSB-darkened plants than in FI plants, which could be
due to the lower total soluble and insoluble sugar concentrations of both GL and GPSB in these plants. 相似文献
119.
Li J Dong Z Liu B Zhuo Y Sun X Yang Z Ge J Tan Z 《Biochemical and biophysical research communications》2011,(1):40-44
Beta-amyloid (Aβ) derived from amyloid precursor protein (APP) has been associated with retinal degeneration in Alzheimer’s disease (AD) and glaucoma. This study examined whether hypoxia exposure induces Aβ accumulation in RGC-5 cells. While levels of APP mRNA and protein significantly increased in the cells, elevated abundance of Aβ was also observed in cells and culture medium between 12 or 24 and 48 h after 5% O2 hypoxia treatment. Additionally, there is a close relationship between induction of APP and Aβ and intracellular accumulation of ROS along with loss of mitochondrial membrane potential followed by the death of RGC-5 cells in culture under hypoxia. These results suggest a possible involvement of APP and Aβ in the death of RGCs challenged by hypoxia. 相似文献
120.