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Macrocyclic Receptors for Biomolecules and Biochemical Sensing
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
Polar lipids such as glycerophospholipids and sterols consisting of polar heads and nonpolar hydrocarbon chain are major components of the cell membrane. Biophysical properties of plasma membrane such as surface curvature and internal fluidity can be modulated by their lipid compositions. The presence of sterols, such as cholesterol or ergosterol, greatly affects the membrane packing and structural integrity (Dufourc 2008). Interaction of lipid molecules with membrane proteins regulates G-protein and GPCRs activity. Sterols are crucial membrane components in the formation of local liquid-ordered membrane phases called ‘lipid rafts’, which also contain transmembrane proteins and are involved in biological signaling and trafficking processes (Simons and Sampaio 2011). Essential Fatty Acids (EFA) are indispensable for one’s health as they serve as dietary precursors for the formation of prostanoids and other eicosanoids important for health and modulation of disease conditions. Poly-Unsaturated Fatty Acids (PUFA) like Omega-3 (w-3) fatty acids is an essential requirement for one’s health which cannot be synthesized by the human physiological system and must therefore be obtained through a nutritional diet (Uauy 1999). The endoplasmic reticulum is the bulk supplier of lipids to other organelles in the eukaryotic cell. The transport and metabolism of lipid is governed by various protein receptors that selectively associate with lipids and transfer them to specific locations with the help of supra-molecular transporting assemblies (Holthuis and Menon 2014).
Introduction: Background Material
Published in Nassir H. Sabah, Neuromuscular Fundamentals, 2020
The endoplasmic reticulum (ER) is an elaborate network of vesicles, tubules, and cisternae. It can take the form of a rough endoplasmic reticulum (RER) because of the presence of ribosomes, which are granular structures that are the sites of protein synthesis. Ribosomes can also be free in the cytosol in addition to being membrane-bound in the RER. The RER is thus involved in the synthesis of integral membrane proteins and proteins that are to be secreted outside the cell, including hormones. The smooth endoplasmic reticulum (SER) is almost devoid of ribosomes and is involved in the synthesis of lipids and steroids and in Ca2+homeostasis, that is, regulation of Ca2+ concentration in the cytosol, by acting as the principal store of Ca2+ in the cell. A type of SER, the sarcoplasmic reticulum (SR), is found in muscle cells (Section 9.1.2) and is specialized for the uptake and release of Ca2+.
Medium Design for Cell Culture Processing
Published in Wei-Shou Hu, Cell Culture Bioprocess Engineering, 2020
Phosphate makes up part of the nucleic acids and nucleotides of cell biomass. It is also present as various phosphorylated metabolic intermediates and as inorganic phosphate. A high level of phosphate in the medium is necessary for carrying out the stoichiometric need to synthesize new biomass. Magnesium plays key metabolic roles in energy metabolism and is conjugated to many metabolites. The intracellular level of Mg2+ is high, but free Mg2+ is only at about ~.25–1 mM, as the majority is complexed to ATP and other organic acids. Phosphate, K+, and Mg2+ are thus three inorganic components that appear at higher concentrations intracellularly than in the medium. Calcium is essential for signaling in some differentiated cells, and is present in high concentrations in the endoplasmic reticulum (ER) and the sarcoplasmic reticulum in muscle cells. The concentrations of the most abundant bulk ions (Na+, Cl−, and K+) in commonly used media spans a small range. In contrast, HCO32+ spans a much wider range.
Lung injury caused by occupational exposure to particles from the industrial combustion of cashew nut shells: a mice model
Published in Archives of Environmental & Occupational Health, 2021
D. S. Serra, R. S. Araujo, M. L. M. Oliveira, F. S. A. Cavalcante, J. H. Leal-Cardoso
Regarding respiratory system mechanics, has been used as a good estimate of total airway resistance;44 this variable showed a significant increase in the SMT group. This may occur because inhaled particles induce the expression of pro-inflammatory mediators and Ca2+-dependent intracellular signaling pathways.45 The presence of Ca2+ ions in the lungs plays a role in the regulation of various functions, such as mucus and surfactant secretion and control of the ciliary agitation frequency.46 After cell stimulation, calcium is released from the endoplasmic reticulum, which in turn leads to an influx of calcium ions through the plasma membrane by means of calcium channels. This accumulation of calcium in the cytosol may lead to further narrowing or increased smooth muscle of the airways,47 increasing the value of Significant changes in in the OST and OMT groups were already expected. In the OST group, the use of the ovalbumin-induced asthma model was the probable cause of the airway inflammation and remodeling,48,49 which may result in an increased It is likely that the hypotheses raised to justify the increased in the SMT and OST groups could be extrapolated to the OMT group.
Circular RNA expression profiles following MC-LR treatment in human normal liver cell line (HL7702) cells using high-throughput sequencing analysis
Published in Journal of Toxicology and Environmental Health, Part A, 2019
Shuilin Zheng, Cong Wen, Shu Yang, Yue Yang, Fei Yang
Endoplasmic reticulum (ER) is a vital organelle in eukaryotes responsible for protein biosynthesis and modification. The protein folding processing in the ER was sensitive to intracellular and extracellular stimulant resulting in the accumulation of misfolded proteins leading to ER stress (ERS) (Chong, Shastri, and Eri 2017). Akamatsu et al. (2009) suggested that ERS affected cellular homeostasis and morphology with reduction of functional proteins and induced cellular apoptosis. Qin et al. (2010) noted that ERS signaling was activated in liver and kidneys of mice after intraperitoneal injection of MC-LR. In our study, target genes of differentially expressed circRNAs induced by MC-LR were also activated by ERS signaling, suggesting the observed liver damage may also be associated with ERS signaling pathway stimulation.
Using chemical chaperones to increase recombinant human erythropoietin secretion in CHO cell line
Published in Preparative Biochemistry and Biotechnology, 2019
Mehri Mortazavi, Mohammad Ali Shokrgozar, Soroush Sardari, Kayhan Azadmanesh, Reza Mahdian, Hooman Kaghazian, Seyed Nezamedin Hosseini, Mohammad Hossein Hedayati
Endoplasmic reticulum is the prominent site of membrane and secretory protein folding. Protein folding is caused by molecular chaperones in ER such as glucose regulated protein 78/immunoglobulin binding protein (GRP78/BiP), X-box binding protein 1 (XBP1), activating transcription factor 4 (ATF4), and activating transcription factor 6 (ATF6).[1] Throughout protein synthesis by ribosomal residues on ER, a quality control process and post-translational modifications take place.[2–4] Recombinant protein overexpression in transfected cell lines usually results in protein misfolding, ER stress, and protein aggregation,[5,6] leading to the unfolded protein response.[7] Molecular chaperones and protein folding enzymes in ER act to solve this problem and help the protein to find its folding.[8] ER stress is induced due to the overload of unfolded, misfolded, and mutate proteins that cannot pass the protein secretion pathway and are stopped in ER.[4] Unfolded protein response (UPR) occurs in case ER stress is sensed by molecular chaperones in ER such as IRE1, PERK, and ATF6. Then GRP is released to reduce protein misfolding, and, at that time, UPR is activated. XBP1 and ATF4 are two other molecular chaperones in ER which are involved in UPR pathway.[1,7]