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排序方式: 共有590条查询结果,搜索用时 15 毫秒
541.
Mohammad Tajfard Latiffah A. Latiff Hamid Reza Rahimi Mohsen Moohebati Mehdi Hasanzadeh Ahmad Sarreshtehdar Emrani Habibollah Esmaeily Ali Taghipour Sayed Reza Mirhafez Gordon A. Ferns Maryam Mardan-Nik Elham Mohammadzadeh Amir Avan Parichehr Hanachi Majid Ghayour-Mobarhan 《Molecular and cellular biochemistry》2017,425(1-2):37-45
The UBA–UBX domain-containing proteins can interact with ubiquitinated substrates and p97 during endoplasmic reticulum-associated degradation (ERAD). Here, we found that the expressions of all UBA–UBX genes p47, SAKS1, UBXD8, FAF1, and UBXD7 were elevated upon ER stress, albeit with different levels. Of which p47, SAKS1, and UBXD8 are ‘immediate’ respondents whereas FAF1 and UBXD7 were ‘late’ respondents to ER stress. Interestingly, the expression of specific UBA–UBX genes were altered in cells stably expressing three different ERAD substrates such as α-TCR, α1-antitrypsin, and δCD3. We first found that p47 and UBXD8 expression levels were increased in α-TCR and α1-antitrypsin stable cell lines, respectively, whereas SAKS1 expression level was reduced in all the three ERAD substrates tested. Of note, we also found p47 promotes, whereas SASK1 delays the degradation of a single ERAD substrate, α-TCR. Additionally, we found that SAKS1 selectively inhibits the degradation of ERAD substrates without affecting cytosolic proteasomal substrates. Taken together, our results identified that UBA–UBX proteins possess substrate selectivity and opposite role of two different UBA–UBX proteins in the degradation of a single ERAD substrate. 相似文献
542.
Maryam Safari Rana Amache Elham Esmaeilishirazifard Tajalli Keshavarz 《Applied microbiology and biotechnology》2014,98(8):3401-3412
The cell-to-cell communication of microorganisms is known to be via exertion of certain chemical compounds (signal molecules) and is referred to as quorum sensing (QS). QS phenomenon is widespread in microbial communities. Several Gram-positive and Gram-negative bacteria and fungi use lactone-containing compounds (e.g. acyl-homoserine lactones (AHLs), γ-heptalactone, butyrolactone-I) as signalling molecules. The ability of microorganisms to metabolise these compounds and the mechanisms they employ for this purpose are not clearly understood. Many studies, however, have focused on identifying AHL and other lactone-degrading enzymes produced by bacteria and fungi. Various strains that are able to utilise these signalling molecules as carbon and energy sources have also been isolated. In addition, several reports have provided evidence on the involvement of lactones and lactone-degrading enzymes in numerous biological functions. These studies, although focused on processes other than metabolism of lactone signalling molecules, still provide insights into further understanding of the mechanisms employed by various microorganisms to metabolise the QS compounds. In this review, we consider conceivable microbial strategies to metabolise AHL and other lactone-containing signalling molecules such as γ-heptalactones. 相似文献
543.
544.
Elham Masoumi Asad Mirzaei Haniyeh Ghaffari-Nazari Sahar Tahaghoghi-Hajghorbani Seyed Amir Jalali Jalil Tavakkol-Afshari 《Reports of Biochemistry & Molecular Biology》2021,9(4):394
Background:The precise responsible mechanism of pre-eclampsia remains controversial however, recent data suggest a main role of the abnormal activation of the adaptive immune system and Apoptosis. In this study, we have measured serum levels of Fas/Fasl as two important members of extrinsic apoptotic pathway in patient with pre-eclampsia.Methods:207 participants including 99 pre-eclampsia patients and 108 age and sex-matched normal pregnant women were involved in the case-control study. Plasma sample from each participant was collected and stored at –20 °C until batch processing.Serum levels of Fas and Fas ligand were measured by ELISA for each participant including 99 pre-eclampsia patients and 108 normal pregnant women. Following a test of statistical normality, nonparametric data were analyzed by Mann-Whitney.Results:sFas levels in case group was significantly higher than controls; 584 (397-892) pg/ml in cases opposed to 341 (213-602) pg/ml in controls (p value< 0.01). sFasL in pre-eclampsia women was a little lower than controls; 255 (173-318) pg/ml and in case group compared to 265.5 (184-381.5) pg/ml in controls.Conclusion:We have found the increased levels of sFas in patients with pre-eclampsia in compare with the healthy pregnant women. It seems that abnormality in sFAS is related with pre-eclampsia.Key Words: Pre-eclampsia, Pregnancy, sFAS, sFASL, Apoptosis 相似文献
545.
Talaei Andisheh Mazaheri Somayeh Bayat Elham Bakhshandeh Behnaz Sabzalinejad Masoumeh Damough Shadi Mahboudi Fereidoun Nematollahi Leila Talebkhan Yeganeh 《The protein journal》2021,40(5):786-798
The Protein Journal - With the increasing dominance of monoclonal antibodies (mAbs) in the biopharmaceutical industry and smaller antibody fragments bringing notable advantages over full-length... 相似文献
546.
Elham Hasanzadeh Ghassem Amoabediny Nooshin Haghighipour Nasim Gholami Javad Mohammadnejad Shahrokh Shojaei Nasim Salehi-Nik 《In vitro cellular & developmental biology. Animal》2017,53(9):818-826
Adipose-derived mesenchymal stem cells (ADSCs) are adult multipotent cells able to differentiate into several cell lineages. Vascular endothelial growth factor (VEGF) and the shear stress associated with blood flow are considered as the most important chemical and mechanical cues that play major roles in endothelial differentiation. However, the stability of endothelial-specific gene expression has not been completely addressed yet. ADSCs in passage 3 were cultured inside the tubular silicon tubes and then exposed to VEGF or shear stress produced in a perfusion bioreactor. To investigate the differentiation, the expression levels of Flk-1, von Willebrand factor (vWF), and vascular endothelial-cadherin (VE-cadherin) were studied using Real-Time PCR. For studying the endothelial differentiation stability, mRNA levels of the genes were evaluated in certain time intervals after completion of the tests so as to determine whether the expression level of each gene in different time points was stable and remained constant or not. Application of VEGF and shear stress caused an elevation in endothelial cells’ specific genes. Although there are some changes following the days after application of mechanical and chemical stimuli, the gene expression results depicted significantly higher gene expression between sequential chemically and mechanically incited groups. In conclusion, stress alone can be a differentiating factor, by itself. Our results verified the efficient stable differentiation ability of the chemical and mechanical factors. 相似文献
547.
548.
Formation of Carbon-Carbon Bonds in the Photochemical Alkylation of Polycyclic Aromatic Hydrocarbons
Mahajan Tania B. Elsila Jamie E. Deamer David W. Zare Richard N. 《Origins of life and evolution of the biosphere》2003,33(1):17-35
The reaction of polycyclic aromatic hydrocarbons (PAHs) withalkanes was examined in the presence of ultraviolet (UV) lightunder model prebiotic Earth and interstellar medium (ISM)conditions. We observed the formation of alkylated PAHs from avariety of PAHs and alkanes, which was caused by the absorptionof UV light by the PAH molecule. Photoalkylation occurred inPAHs and alkanes in solution, in thin films in contact withsimulated ocean water, and in matrices simulating ISMconditions. Photoalkylation occurred readily, with significantproduct yields within 5 h of irradiation. Because alkanes andPAHs are presumed to be part of the organic inventory in the ISMand on the early Earth, we propose that this photoalkylation reactionis a plausible pathway for the formation of carbon-carbon bondsin both these environments. 相似文献
549.
Elham Hatami Ying Mu Deanna N. Shields Subhash C. Chauhan Santosh Kumar Theodore J. Cory Murali M. Yallapu 《Biochemistry and Biophysics Reports》2019
Our goal was to design nanocarriers that specifically target and deliver therapeutics to polarized macrophages. Mannose receptors are highly overexpressed on polarized macrophages. In this study, we constructed Pluronic® -F127 polymer and tannic acid (TA) based nanoparticles (F127-TA core nanoparticles) with varying mannose densities. The particle size of the optimized mannose-decorated F127-TA hybrid nanoparticles (MDNPs) was found to be ~ 265 nm with a negative zeta potential of ~ ? 4.5 mV. No significant changes in the size and zeta potentials of nanoparticles were observed, which demonstrated structural integrity and stability of the nanoformulation. Physicochemical characteristics of MDNPs were evaluated by FTIR and TGA and demonstrated the presence of mannose units on surface nanoparticles. A mannose-dependent cellular targeting and uptake of MDNPs was found in U937 macrophages. The uptake process was found to vary directly with time and volume of MDNPs nanoparticles. The uptake pattern is higher in M2 than M1. This behavior was also evident from the instantaneous and superior binding profile of M2 macrophage lysate protein with MDNPs over that of M1 macrophage lysate protein. These results demonstrated that an appropriate mannose ligand density was confirmed, suggesting efficient targeting of M2. Altogether, these data support that the MDNPs formulation could serve as a targeted therapeutic guide in the generation of nanomedicine to treat various conditions as an anti-inflammation therapy. 相似文献
550.
Hormonal regulation of oligopeptide transporter Pept-1 in a human intestinal cell line 总被引:12,自引:0,他引:12
Thamotharan Manikkavasagar; Bawani Shahab Zare; Zhou Xiaodong; Adibi Siamak A. 《American journal of physiology. Cell physiology》1999,276(4):C821
The intestinal oligopeptide transporter (cloned as Pept-1) hasmajor roles in protein nutrition and drug therapy. A key unstudied question is whether expression of Pept-1 is hormonally regulated. Inthis experiment, we investigated whether insulin has such a role. Weused a human intestinal cell monolayer (Caco-2) as the in vitro modelof human small intestine and glycylglutamine (Gly-Gln) as the modelsubstrate for Pept-1. Results showed that addition of insulin at aphysiological concentration (5 nM) to incubation medium greatlystimulates Gly-Gln uptake by Caco-2 cells. This stimulation was blockedwhen genistein, an inhibitor of tyrosine kinase, was added toincubation medium. Studies of the mechanism of insulin stimulationshowed the following. 1) Stimulationoccurred promptly (30-60 min) after exposure to insulin.2) There was no significant changein the Michaelis-Menten constant of Gly-Gln transport, but there was anearly twofold increase in its maximal velocity.3) Insulin effect persisted evenwhen Golgi apparatus, which is involved in trafficking of newlysynthesized Pept-1, was dismantled.4) However, there was completeelimination of insulin effect by disruption of microtubules involved intrafficking of preformed Pept-1. 5)Finally, with insulin treatment, there was no change in Pept-1 geneexpression, but the amount of Pept-1 protein in the apical membrane wasincreased. In conclusion, the results show that insulin, when it bindsto its receptor, stimulates Gly-Gln uptake by Caco-2 cells byincreasing the membrane population of Pept-1. The mechanism appears tobe increased translocation of this transporter from a preformedcytoplasmic pool. 相似文献