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751.
Nigel J. Pyne Catherine M. Waters Jaclyn S. Long Noreen A. Moughal Gabor Tigyi Susan Pyne 《Advances in enzyme regulation》2007,47(1):271-280
We describe here formation of a novel functional signaling complex between RTK and GPCRπ. This permits the use of activated G-protein subunits by the RTK in response to growth factor and that are made available by the constitutive activity of the GPCR or by binding of ligand to the latter. Moreover, β-arrestin associates with the receptor complex and participates in growth factor-dependent recruitment of c-Src, whereupon the kinase is activated by Gβγ subunits. This enables signal relay to down-stream effectors such as p42/p44 mitogen-activated protein kinases. The novel RTK–GPCR complex is involved in regulating important cellular responses, such as growth and cell migration, and dysfunction of this complex might play a significant role in hyperplasic disease states. 相似文献
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Robertson G.H.; Mahoney N.E.; Goodman N.; Pavlath A.E. 《Journal of experimental botany》1995,46(6):667-673
The onium compound 2(4-chlorophenylthio)-triethylamine(CPTA) was used to increase lycopene formation to levels approximatingthose in fieldor glasshousegrown fruit, and then growthregulators, sucrose and temperature were used to regulate lycopeneaccumulation. It was found that the native auxin indole3acetic acid (IAA) was substantially more effective than 2,4-dichlorophenoxyaceticacid (2,4D) in promoting lycopene formation, sucroseinhibited lycopene formation (cell basis), and temperature produceda pattern similar to that observed in the field with a temperatureoptimum between 18 and 26 C. Suggestions for further improvementsin technique are included. Key words: Suspension culture, tomato, lycopene 相似文献
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John K. Mich Lucas T. Graybuck Erik E. Hess Joseph T. Mahoney Yoshiko Kojima Yi Ding Saroja Somasundaram Jeremy A. Miller Brian E. Kalmbach Cristina Radaelli Bryan B. Gore Natalie Weed Victoria Omstead Yemeserach Bishaw Nadiya V. Shapovalova Refugio A. Martinez Olivia Fong Shenqin Yao Boaz P. Levi 《Cell reports》2021,34(13):108754
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Chicken embryos have been proven to be an attractive vertebrate model for biomedical research. They have helped in making significant contributions for advancements in various fields like developmental biology, cancer research and cardiovascular studies. However, a non‐invasive, label‐free method of imaging live chicken embryo at high resolution still needs to be developed and optimized. In this work, we have shown the potential of photoacoustic tomography (PAT) for imaging live chicken embryos cultured in bioengineered eggshells. Laser pulses at wavelengths of 532 and 740 nm were used for attaining cross‐sectional images of chicken embryos at different developmental stages. Cross‐sections along different depths were imaged to gain knowledge of the relative depth of different vessels and organs. Due to high optical absorption of vasculature and embryonic eye, images with good optical contrast could be acquired using this method. We have thus reported a label‐free method of performing cross‐sectional imaging of chicken embryos at high resolution demonstrating the capacity of PAT as a promising tool for avian embryo imaging. 相似文献
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Effects of recombinant murine interferon-γ (rIFN-γ) on the membrane adenylate cyclase of a murine macrophage cell line (P388D1) were investigated in order to explore the nature of a signal transmitted by IFN-γ receptor. Following the incubation of P388D1 cells with 40 U/ml of rIFN-γ, the intracellular level of cAMP gradually increased about twofold over the control level within 60 min, and then began to gradually decline to about half the control level by 24 h incubation. The initial rise in cAMP level appeared to be due to the modest activation of adenylate cyclase and not due to the inhibition of cAMP-phosphodiesterase. Later decrease of intracellular cAMP may be due to quantitative down-regulation of the adenylate cyclase system. The basal enzymatic activity of the membrane prepared from P388D1 cells exposed to IFN-γ for 24 h was found to be reduced to about 20% of that of the control membrane. However, the quality of the adenylate cyclase system appeared unchanged, because the relative degree of the response of the down-regulated membrane adenylate cyclase to prostaglandin PGE2, NaF, guanylimidodiphosphate (GppNHp), cholera toxin (CT), or forskolin was found to remain unchanged. This quantitative down-regulation of adenylate cyclase must be due to the action of rIFN-γ, since the prior treatment of rIFN-γ with either acid (pH 2) or monoclonal anti-IFN-γ antibody inhibited the ability of IFN-γ to induce the down-regulation. The rIFN-γ-induced down-regulation is a reversible process, since the adenylate cyclase activity of the membrane was found to be restored when the rIFN-γ-exposed cells were cultured for 72 h in the absence of rIFN-γ. In addition, the 48 h-incubation of P388D1 cells with rIFN-β or IFN-α was found not to significantly affect the membrane adenylate cyclase system. 相似文献