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51.
Protein phosphokinase activity of rat liver nuclear membrane 总被引:3,自引:0,他引:3
The presence of protein phosphokinase activity in a purified nuclear-membrane preparation from adult rat liver was demonstrated by measuring the incorporation of 32P from γ-32P-ATP into endogenous nuclear-membrane proteins as well as into the exogenous protein substrates, dephosphophosvitin (DPV) and lysine-rich histone (LRH). The activity of this enzyme toward DPV was 60 times greater than that toward LRH. cAMP and cGMP did not appear to affect the phosphorylation of endogenous-membrane proteins. 相似文献
52.
A protein phosphatase activity has been demonstrated in nuclei of rat ventral prostate utilizing 32P-labelled phosvitin as a model acidic phosphoprotein substrate. This phosphoprotein phosphatase has a pH optimum of 6.7, is unaffected by the sulphydryl protecting agent 2-mercaptoethanol, and requires a divalent cation for maximal activity. Of the various divalent cations tested, Mg2+ is the most effective in reactivating the EDTA-inhibited enzyme. The phosphatase is inhibited by sodium flouride, sodium oxalate, N-ethylmaleimide, ATP and ADP but is relatively insensitive to ammonium molybdate. Increased ionic strength of the reaction medium also causes a reduction in the enzyme activity, e.g., by 48% at 200 mM sodium chloride. The activity of the acidic phosphoprotein phosphatase did not change significantly at 48 h or 96 h post-orchiectomy when expressed per unit of nuclear protein. However, it is reduced by approx. 30% at these times after castration if based on DNA content. The decline in activity per nucleus reflects the decrease in the realtive nuclear protein content observed at 48 h or 96 h post-orchiectomy. This suggests that the decline in the phosphorylation of prostatic nuclear acidic proteins which occurs upon androgen withdrawal is not due to increased nuclear phosphatase activity. 相似文献
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54.
Six cold-sensitive variants have been isolated from Chinese hamster ovary cells by the BUdR-visible light selection technique. The properties of one of these lines have been studied in detail. This line stops dividing immediately after a shift from 39 degrees C to 33 degrees C though its doubling time at 39 degrees C is only slightly longer than that of wild-type cells. The rates of DNA and protein synthesis are severely reduced at 33 degrees C, but the rate of RNA synthesis is not significantly different from wild-type cells. This line may be defective in protein synthesis, but the results of sedimentation analysis indicate that it probably has normal ribosomal subunit assembly. 相似文献
55.
Mohammed S. Taghour Hazem Elkady Wagdy M. Eldehna Nehal M. El-Deeb Ahmed M. Kenawy Eslam B. Elkaeed Aisha A. Alsfouk Mohamed S. Alesawy Ahmed M. Metwaly Ibrahim. H. Eissa 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1903
A thiazolidine-2,4-dione nucleus was molecularly hybridised with the effective antitumor moieties; 2-oxo-1,2-dihydroquinoline and 2-oxoindoline to obtain new hybrids with potential activity against VEGFR-2. The cytotoxic effects of the synthesised derivatives against Caco-2, HepG-2, and MDA-MB-231 cell lines were investigated. Compound 12a was found to be the most potent candidate against the investigated cell lines with IC50 values of 2, 10, and 40 µM, respectively. Furthermore, the synthesised derivatives were tested in vitro for their VEGFR-2 inhibitory activity showing strong inhibition. Moreover, an in vitro viability study against Vero non-cancerous cell line was investigated and the results reflected a high safety profile of all tested compounds. Compound 12a was further investigated for its apoptotic behaviour by assessing the gene expression of four genes (Bcl2, Bcl-xl, TGF, and Survivin). Molecular dynamic simulations authenticated the high affinity, accurate binding, and perfect dynamics of compound 12a against VEGFR-2. 相似文献
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57.
Mahmudul Hasan Rifat Jamil Ahmed Milad Ahmed Foeaz Ahmed Airin Gulshan Mahmudul Hasan 《PLoS computational biology》2022,18(6)
Accelerated cell death 11 (ACD11) is an autoimmune gene that suppresses pathogen infection in plants by preventing plant cells from becoming infected by any pathogen. This gene is widely known for growth inhibition, premature leaf chlorosis, and defense-related programmed cell death (PCD) in seedlings before flowering in Arabidopsis plant. Specific amino acid changes in the ACD11 protein’s highly conserved domains are linked to autoimmune symptoms including constitutive defensive responses and necrosis without pathogen awareness. The molecular aspect of the aberrant activity of the ACD11 protein is difficult to ascertain. The purpose of our study was to find the most deleterious mutation position in the ACD11 protein and correlate them with their abnormal expression pattern. Using several computational methods, we discovered PCD vulnerable single nucleotide polymorphisms (SNPs) in ACD11. We analysed the RNA-Seq data, identified the detrimental nonsynonymous SNPs (nsSNP), built genetically mutated protein structures and used molecular docking to assess the impact of mutation. Our results demonstrated that the A15T and A39D mutations in the GLTP domain were likely to be extremely detrimental mutations that inhibit the expression of the ACD11 protein domain by destabilizing its composition, as well as disrupt its catalytic effectiveness. When compared to the A15T mutant, the A39D mutant was more likely to destabilize the protein structure. In conclusion, these mutants can aid in the better understanding of the vast pool of PCD susceptibilities connected to ACD11 gene GLTP domain activation. 相似文献
58.
Proper balance between self-renewal and differentiation of lung-specific progenitors is absolutely required for normal lung morphogenesis/regeneration. Therefore, understanding the behavior of lung epithelial stem/progenitor cells could identify innovative solutions for restoring normal lung morphogenesis and/or regeneration. The Notch inhibitor Numb is a key determinant of asymmetric or symmetric cell division and hence cell fate. Yet Numb proximal-distal expression pattern and symmetric versus asymmetric division are uncharacterized during lung epithelial development. Herein, the authors find that the cell fate determinant Numb is highly expressed and asymmetrically distributed at the apical side of distal epithelial progenitors and segregated to one daughter cell in most mitotic cells. Knocking down Numb in MLE15 epithelial cells significantly increased the number of cells expressing the progenitor cell markers Sox9/Id2. Furthermore, cadherin hole analysis revealed that most distal epithelial stem/progenitor cells in embryonic lungs divide asymmetrically; with their cleavage, planes are predicted to bypass the cadherin hole, resulting in asymmetric distribution of the cadherin hole to the daughter cells. These novel findings provide evidence for asymmetric cell division in distal epithelial stem/progenitor cells of embryonic lungs and a framework for future translationally oriented studies in this area. 相似文献
59.
Eman M. Alissa Suhad M. Bahjri Waqar H. Ahmed Nabeel Al-Ama Gordon A. A. Ferns 《Biological trace element research》2009,131(3):215-228
Chromium deficiency is associated with impaired glucose tolerance (IGT) and dyslipidemia. Hence, the objective of the current
study was to investigate chromium status among Saudi men with and without established cardiovascular disease (CVD) and its
relationship to glucose tolerance, lipid profile and other established CVD risk factors. We measured serum and urine chromium
concentrations, fasted lipid profile, plasma glucose, and serum lipid peroxide in 130 Saudi men with an established history
of myocardial infarction and 130 age-matched controls without established CVD. Patients with established CVD had higher serum
triglycerides (p < 0.05) and plasma glucose (p < 0.0001) and lower serum and urinary chromium concentrations (p < 0.0001) than controls. Serum chromium was inversely correlated with plasma glucose among cases and controls (r = −0.189, p < 0.05 and r = −0.354, p < 0.00001, respectively). Plasma glucose (OR 1.127, CI 1.0–1.269, p < 0.05), serum chromium (OR 0.99, CI 0.985–0.995, p < 0.0001), and urinary chromium (OR 0.988, CI 0.981–0.995, p < 0.001) were independently associated with the presence of established coronary disease applying this model. While chromium
metabolism appears to be altered in individuals with CVD, it is unclear whether chromium supplementation would be effective
in CVD prevention among patients with IGT. This would need to be tested in long-term outcome trials. 相似文献
60.