1,358 results on '"Membrane bound"'
Search Results
52. Helix Fraying and Lipid-Dependent Structure of a Short Amphipathic Membrane-Bound Peptide Revealed by Solid-State NMR
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Erik Strandberg, Anne S. Ulrich, Francesc Rabanal, Jochen Bürck, Parvesh Wadhwani, and Ariadna Grau-Campistany
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Protein Conformation, alpha-Helical ,0301 basic medicine ,Circular dichroism ,Membrane bound ,Lipid Bilayers ,Peptide ,Membranes (Biology) ,010402 general chemistry ,01 natural sciences ,03 medical and health sciences ,Membranes (Biologia) ,Amphiphile ,Materials Chemistry ,Amino Acid Sequence ,Physical and Theoretical Chemistry ,Nuclear Magnetic Resonance, Biomolecular ,chemistry.chemical_classification ,Chemistry ,Circular Dichroism ,Nuclear magnetic resonance spectroscopy ,0104 chemical sciences ,Surfaces, Coatings and Films ,Crystallography ,030104 developmental biology ,Membrane ,Solid-state nuclear magnetic resonance ,Phosphatidylcholines ,lipids (amino acids, peptides, and proteins) ,Pèptids ,Peptides ,Alpha helix - Abstract
The amphipathic a-helical peptide KIA14 [(KIAGKIA)(2)-NH2] was studied in membranes using circular dichroism and solid-state NMR spectroscopy to obtain global as well as local structural information. By analyzing H-2 NMR data from 10 analogues of KIA14 that were selectively labeled with Ala-d(3), those positions that are properly folded into a helix could be determined within the membrane-bound peptide. The N-terminus was found to be unraveled, whereas positions 4-14 formed an ideal helix all the way to the C-terminus. The helicity did not change when Gly residues were replaced by Ala-d3 but was reduced when Ile was replaced, indicating that large hydrophobic residues are required for membrane binding and helix formation. The reduced helicity was strongly correlated with a decrease in peptide-induced leakage from lipid vesicles. The orientation of the short KIA14 peptide was assessed in several lipid systems and compared with that of the longer KIA21 sequence [(KIAGKIA)(3)-NH2]. In 1,2-dioleoylsn-glycero-3-phosphatidylcholine, both peptides are aligned flat on the membrane surface, whereas in 1,2-dimyristoyl-sn-glycero3-phosphatidylcholine (DMPC)/1-myristoy1-2-hydroxy-sn-glycero-3-phosphatidylcholine (lyso-MPC) both are inserted into the membrane in an upright orientation. These two types of lipid systems had been selected for their strongly negative and positive spontaneous curvature, respectively. We propose that in these cases, the peptide orientation is largely determined by the lipid properties. On the other hand, in plain DMPC and 1,2-dilauroyl-sn-glycero-3-phosphatidylcholine, which have only a slight positive curvature, a marked difference in orientation is evident: the short KIA14 lies almost flat on the membrane surface, whereas the longer KIA21 is more tilted. We thus propose that out of the lipid systems tested here, DMPC (with hardly any curvature) is the least biased,lipid system in which peptide orientation and realignment can be studied, allowing to compare and discriminate the intrinsic effects of the properties of the peptides as such.
- Published
- 2018
53. Cardiac Kir2.1 and Na V 1.5 Channels Traffic Together to the Sarcolemma to Control Excitability
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Eva Delpón, Rafael J. Ramirez, Marcos Matamoros, Todd J. Herron, Daniela Ponce-Balbuena, Kuljeet Kaur, Héctor H. Valdivia, Manuel Zarzoso, Francisco J. Alvarado, B. Cicero Willis, Eric N. Jiménez-Vázquez, F. Javier Díez-Guerra, José Jalife, Ricardo Caballero, Carmen R. Valdivia, Andre Monteiro da Rocha, Guadalupe Guerrero-Serna, Marta Pérez-Hernández, and Katherine Campbell
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0301 basic medicine ,Sarcolemma ,biology ,Physiology ,Chemistry ,Membrane bound ,Kir2.1 ,Heart ,Nav1.5 ,Golgi apparatus ,Article ,NAV1.5 Voltage-Gated Sodium Channel ,03 medical and health sciences ,symbols.namesake ,Electrophysiology ,030104 developmental biology ,cardiovascular system ,biology.protein ,symbols ,Biophysics ,Macromolecular Complexes ,Cardiology and Cardiovascular Medicine ,Ion channel - Abstract
Rationale: In cardiomyocytes, Na V 1.5 and Kir2.1 channels interact dynamically as part of membrane bound macromolecular complexes. Objective: The objective of this study was to test whether Na V 1.5 and Kir2.1 preassemble during early forward trafficking and travel together to common membrane microdomains. Methods and Results: In patch-clamp experiments, coexpression of trafficking-deficient mutants Kir2.1 Δ314-315 or Kir2.1 R44A/R46A with wild-type (WT) Na V 1.5 WT in heterologous cells reduced inward sodium current compared with Na V 1.5 WT alone or coexpressed with Kir2.1 WT . In cell surface biotinylation experiments, expression of Kir2.1 Δ314-315 reduced Na V 1.5 channel surface expression. Glycosylation analysis suggested that Na V 1.5 WT and Kir2.1 WT channels associate early in their biosynthetic pathway, and fluorescence recovery after photobleaching experiments demonstrated that coexpression with Kir2.1 increased cytoplasmic mobility of Na V 1.5 WT , and vice versa, whereas coexpression with Kir2.1 Δ314-315 reduced mobility of both channels. Viral gene transfer of Kir2.1 Δ314-315 in adult rat ventricular myocytes and human induced pluripotent stem cell–derived cardiomyocytes reduced inward rectifier potassium current and inward sodium current, maximum diastolic potential and action potential depolarization rate, and increased action potential duration. On immunostaining, the AP1 (adaptor protein complex 1) colocalized with Na V 1.5 WT and Kir2.1 WT within areas corresponding to t-tubules and intercalated discs. Like Kir2.1 WT , Na V 1.5 WT coimmunoprecipitated with AP1. Site-directed mutagenesis revealed that Na V 1.5 WT channels interact with AP1 through the Na V 1.5 Y1810 residue, suggesting that, like for Kir2.1 WT , AP1 can mark Na V 1.5 channels for incorporation into clathrin-coated vesicles at the trans -Golgi. Silencing the AP1 ϒ-adaptin subunit in human induced pluripotent stem cell–derived cardiomyocytes reduced inward rectifier potassium current, inward sodium current, and maximum diastolic potential and impaired rate-dependent action potential duration adaptation. Conclusions: The Na V 1.5-Kir2.1 macromolecular complex pre-assembles early in the forward trafficking pathway. Therefore, disruption of Kir2.1 trafficking in cardiomyocytes affects trafficking of Na V 1.5, which may have important implications in the mechanisms of arrhythmias in inheritable cardiac diseases.
- Published
- 2018
54. Heterocyclic periphery in the design of carbonic anhydrase inhibitors: 1,2,4-Oxadiazol-5-yl benzenesulfonamides as potent and selective inhibitors of cytosolic hCA II and membrane-bound hCA IX isoforms
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Mikhail Krasavin, Claudiu T. Supuran, Andrea Angeli, Stanislav Kalinin, Anton Shetnev, Sergey V. Baykov, Tiziano Tuccinardi, and Tatyana Sharonova
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Gene isoform ,Nanomolar inhibition ,Membrane bound ,Stereochemistry ,Acylation ,Carbonic Anhydrase II ,01 natural sciences ,Biochemistry ,Periphery groups ,Structure-Activity Relationship ,Antigens, Neoplasm ,Cyclodehydration ,Carbonic anhydrase ,Drug Discovery ,Superbase ,Humans ,Carbonic Anhydrase IX ,Carbonic Anhydrase Inhibitors ,Isoform-selective inhibitors ,Molecular Biology ,Cellular localization ,Enzyme Assays ,chemistry.chemical_classification ,Oxadiazoles ,Sulfonamides ,Binding Sites ,Molecular Structure ,4-Oxadiazole ,biology ,010405 organic chemistry ,Drug Discovery3003 Pharmaceutical Science ,Organic Chemistry ,0104 chemical sciences ,Molecular Docking Simulation ,1,2,4-Oxadiazole ,Primary sulfonamides ,010404 medicinal & biomolecular chemistry ,Cytosol ,Enzyme ,chemistry ,Docking (molecular) ,Drug Design ,biology.protein - Abstract
A series of novel aromatic primary sulfonamides decorated with diversely substituted 1,2,4-oxadiazole periphery groups has been prepared using a parallel chemistry approach. The compounds displayed a potent inhibition of cytosolic hCA II and membrane-bound hCA IX isoforms. Due to a different cellular localization of the two target enzymes, the compounds can be viewed as selective inhibition tools for either isoform, depending on the cellular permeability profile. The SAR findings revealed in this study has been well rationalized by docking simulation of the key compounds against the crystal structures of the relevant hCA isoforms.
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- 2018
55. Expression of soluble and membrane-bound programmed death protein 1 in psoriasis vulgaris patients
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Noha Nagui, Hagar El Sayed, Laila A. Rashed, and Khadiga S. Sayed
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business.industry ,Membrane bound ,Case-control study ,Dermatology ,medicine.disease ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Psoriasis ,medicine ,Cancer research ,business ,Programmed death - Published
- 2018
56. Characterization of the growth plate-bone interphase region using cryo-FIB SEM 3D volume imaging
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Keren Kahil, Neta Varsano, Steve Weiner, Katya Rechav, Lia Addadi, and Heden Haimov
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Mineralized tissues ,Membrane bound ,Basement Membrane ,Calcification, Physiologic ,Chondrocytes ,Imaging, Three-Dimensional ,Blood serum ,Structural Biology ,Morphogenesis ,medicine ,Animals ,Bone formation ,Growth Plate ,Mice, Inbred BALB C ,Bone Development ,Tibia ,Chemistry ,Cartilage ,Cryoelectron Microscopy ,Cell Differentiation ,Extracellular Matrix ,Characterization (materials science) ,medicine.anatomical_structure ,Microscopy, Electron, Scanning ,Biophysics ,Blood Vessels ,Female ,Interphase ,Blood vessel - Abstract
The interphase region at the base of the growth plate includes blood vessels, cells and mineralized tissues. In this region, cartilage is mineralized and replaced with bone. Blood vessel extremities permeate this space providing nutrients, oxygen and signaling factors. All these different components form a complex intertwined 3D structure. Here we use cryo-FIB SEM to elaborate this 3D structure without removing the water. As it is challenging to image mineralized and unmineralized tissues in a hydrated state, we provide technical details of the parameters used. We obtained two FIB SEM image stacks that show that the blood vessels are in intimate contact not only with cells, but in some locations also with mineralized tissues. There are abundant red blood cells at the extremities of the vessels. We also documented large multinucleated cells in contact with mineralized cartilage and possibly also with bone. We observed membrane bound mineralized particles in these cells, as well as in blood serum, but not in the hypertrophic chondrocytes. We confirm that there is an open pathway from the blood vessel extremities to the mineralizing cartilage. Based on the sparsity of the mineralized particles, we conclude that mainly ions in solution are used for mineralizing cartilage and bone, but these are augmented by the supply of mineralized particles.
- Published
- 2021
57. A Bicistronic Vector Expressing CD16 and a Membrane Bound IL-15 Construct in iPSC Derived NK Cells Increased Cytotoxicity and Persistence
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Laura C Blaha, John A. Zuris, Alexander G Allen, Kate Zhang, Jared A Getgano, Kevin Wasko, Mark S Shearman, Kaitlyn M Izzo, Rithu Pattali, and Kai-Hsin Chang
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Chemistry ,Interleukin 15 ,Membrane bound ,Immunology ,Cell Biology ,Hematology ,Vector (molecular biology) ,CD16 ,Cytotoxicity ,Biochemistry ,Persistence (computer science) ,Cell biology - Abstract
Current cell and gene therapy medicines for oncology have reshaped how cancer is treated. Specifically, chimeric antigen receptor (CAR)-T cells have demonstrated that cell therapy can achieve durable remissions in hematologic malignancies. However, CAR-T cell therapies have limited efficacy in solid tumors and are often associated with severe toxicity, highlighting the need for novel cell therapies that are safer and more efficacious. With their intrinsic killing capacity of tumor cells and few, if any, treatment related toxicities, natural killer (NK) cell therapies represent an attractive alternative therapy option to CAR-T cells. In addition, NK cells can be generated from allogeneic donors and given to patients off-the-shelf without causing graft versus host disease. Of the various sources of donor types to generate NK cells from, induced pluripotent stem cells (iPSCs) have the unique advantage of being a renewable source. A clone with any desired edits to enhance the effector function of NK cells can be derived, fully characterized, and expanded indefinitely, to generate large quantities of a naturally allogeneic medicine, therefore streamlining the manufacturing process and increasing scalability. Here, a bicistronic cargo encoding CD16 and a membrane-bound IL-15 (mbIL-15) was knocked into iPSCs at the GAPDH locus using an engineered and highly active AsCas12a. The promoter at the GAPDH locus drives robust constitutive expression of inserted cargos and avoids the promoter silencing that often occurs during differentiation with other strategies. CD16 and mbIL-15 were selected as Knock-Ins (KI) to specifically enhance NK cell therapy in two areas, namely NK cell deactivation caused by CD16 downregulation, and the reliance of co-administration of cytokines such as IL-15 or IL-2 for persistence. CD16 (FcRyIII) can bind the Fc portion of IgG antibodies triggering the lysis of targeted cells. This mechanism of cytotoxicity is known as antibody dependent cellular cytotoxicity (ADCC), and is an innate immune response largely mediated by NK cells through CD16. ADCC is severely impaired when surface CD16 is cleaved by a metalloprotease known as ADAM17. By having CD16 expressed from the GAPDH locus, there is consistent CD16 protein expression to replace what is shed. This hypothesis was demonstrated by performing flow cytometry before and after a cytotoxicity assay. WT cells showed a marked reduction in the surface level expression of CD16 compared to CD16 KI cells after tumor cell exposure. Using a lactate dehydrogenase (LDH) release assay as a measure of cytotoxicity, only the iNK cells expressing the CD16 construct showed statistically significant increases in cytotoxicity when trastuzumab was added. Furthermore, to better model a solid tumor, a 3D tumor spheroid killing assay was utilized where CD16 KI cells showed an increase in ADCC capacity. The benefit of increased effector function via CD16 KI cannot be fully realized without iNK cells persisting. IL-2 or IL-15 is needed for NK maintenance but the administration of either cytokine is associated with acute clinical toxicities. mbIL-15 allows NK cells to survive for a prolonged period without the support of homeostatic cytokines. An in vitro persistence assay was performed that demonstrated IL-15 KI cells showed an increase in persistence compared to WT cells. Specifically, during the three-week in vitro assay, WT cells became undetectable by Day 14 while IL-15 KI NK cells remained stable over time. In summary, to overcome two shortfalls of NK cell therapies, a bicistronic construct encoding CD16 and a mbIL-15 was knocked into the GAPDH locus of iPSCs. The strong GAPDH promoter drove constitutive expression of CD16 that mitigated CD16 shedding, enhanced ADCC of iNK cells, which can be used in combination with any ADCC enabling IgG1 and IgG3 antibodies, such as trastuzumab and rituximab, for tumor-specific targeting. In addition, mbIL-15 KI allowed iNK cells to persist without exogenous cytokine administration and thus can circumvent exogeneous cytokine-induced clinical toxicities. CD16 and mbIL-15 double KI iNKs, with enhanced ADCC and increased cytokine-independent persistence, can potentially be developed into a safe and efficacious therapy for the treatment of a variety of liquid and solid tumors with high unmet medical needs. Disclosures Allen: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Pattali: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Izzo: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Getgano: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Wasko: Editas Medicine: Current equity holder in publicly-traded company, Ended employment in the past 24 months. Blaha: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Zuris: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Zhang: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Shearman: Editas Medicine: Current Employment, Current equity holder in publicly-traded company. Chang: Editas Medicine: Current Employment, Current equity holder in publicly-traded company.
- Published
- 2021
58. Comparison of biochemical properties and thermal inactivation of membrane-bound polyphenol oxidase from three apple cultivars (Malus domestica Borkh)
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Yuanying Ni, Fang Liu, and Qianyun Han
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Catechol ,Malus ,biology ,Kinetic model ,Chemistry ,Membrane bound ,010401 analytical chemistry ,04 agricultural and veterinary sciences ,biology.organism_classification ,040401 food science ,01 natural sciences ,Polyphenol oxidase ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,Ph range ,Cultivar ,Food Science ,Nuclear chemistry - Abstract
A comparative study of the properties of membrane‐bound polyphenol oxidase (mPPO) from three apple cultivars, namely Red Fuji (FJ), Granny Smith (GS) and Golden Delicious (GD), was carried out for the first time. Data indicate that mPPOs from three cultivars exhibit significantly different properties. GS mPPO had the strongest affinity to catechol, but FJ mPPO had the highest maximum velocity. Red Fuji (FJ) mPPO had the significantly higher activity than those of GD and GS mPPOs. Red Fuji (FJ) mPPO had the highest activity at pH 8.00, while GD and GS mPPOs at 4.50 and 7.50–8.00, respectively. Red Fuji (FJ) mPPO was more stable than GD and GS mPPOs over the pH range of 5.0–8.5. The optimal temperature for GS mPPO was within 70–75 °C, which is higher than those for mPPOs from FJ and GD. Thermal inactivation of the three mPPOs followed a first‐order kinetic model with different inactivation kinetic parameters.
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- 2017
59. Membrane-bound Heat Shock Protein HSP70 as a Target for Theranostics of Tumors
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Irina V. Guzhova, Gabriele Multhoff, A. Simbirtsev, Boris A. Margulis, B. Nikolaev, Alexander M. Ischenko, and Maxim Shevtsov
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Membrane bound ,Chemistry ,Heat shock protein ,Immunology ,Biophysics ,General Medicine ,Hsp70 - Published
- 2018
60. Interaction of Membrane Bound Proteins with Phosphoinositide-containing Membranes
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Eiji Yamamoto
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Membrane ,Chemistry ,Membrane bound ,Biophysics - Published
- 2021
61. Front Cover Picture: Biocatalytic Application of a Membrane‐Bound Coumarin C‐Glucosyltransferase in the Synthesis of Coumarin and Benzofuran C‐Glucosides (Adv. Synth. Catal. 22/2021)
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Shuai Fan, Dawei Chen, Zhaoyong Yang, and Jungui Dai
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chemistry.chemical_compound ,Front cover ,chemistry ,biology ,Stereochemistry ,Membrane bound ,biology.protein ,Glucosyltransferase ,General Chemistry ,Benzofuran ,Coumarin - Published
- 2021
62. PySeg in Scipion: making easier template-free detection and classification of membrane-bound complexes in cryo-electron tomograms
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Antonio Martinez-Sanchez
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Inorganic Chemistry ,Template free ,Crystallography ,Materials science ,Structural Biology ,Membrane bound ,General Materials Science ,Electron ,Tomography ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Biochemistry - Published
- 2021
63. Comparison of the characterization and the temperature/pressure stability of soluble and membrane-bound polyphenol oxidase from ‘Lijiang’ snow peach
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Yi Junjie, Huihui Niu, Hengle Zhou, Fuhai Wang, Linyan Zhou, Fengyun Cheng, and Lei Yuan
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0106 biological sciences ,Membrane bound ,Substrate (chemistry) ,04 agricultural and veterinary sciences ,Thermal treatment ,040401 food science ,01 natural sciences ,Polyphenol oxidase ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,010608 biotechnology ,Caffeic acid ,Food Science ,Nuclear chemistry - Abstract
The characterization of soluble polyphenol oxidase (sPPO) and membrane-bound (mPPO) from ‘Lijiang snow’ peach was compared, and the inactivation effects by thermal treatment ranging from 45 to 85 °C and high-pressure processing at 550 MPa for 10–50 min were investigated. sPPO and mPPO both showed optimum activity at pH 7.0, while another optimum pH at 5.0 was observed for mPPO. The optimum temperatures for sPPO and mPPO were 30 °C and 50 °C, respectively. The optimum substrate of sPPO was caffeic acid, while mPPO showed the highest activity against 4-methylcatechol. All inhibitors showed poorer inhibitory effects on mPPO compared with sPPO. According to kinetic parameters, sPPO and mPPO were well described by the first-order model and the fractional-conversion model, respectively. The activity of sPPO was activated after HPP at 550 MPa for 20–50 min, while mPPO was more stable under the treatment conditions investigated.
- Published
- 2021
64. Investigating homeopathic potencies with membrane bound solvatochromic dyes
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Steven Cartwright
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Membrane ,Excited electronic state ,Complementary and alternative medicine ,Chemistry ,Membrane bound ,Covalent bond ,Computational chemistry ,Bathochromic shift ,Solvatochromism ,Chromophore - Abstract
Background Solvatochromic dyes have demonstrated themselves to be useful probes in the molecular-level study of homeopathic potencies. The range of dyes available, and their broad division into two main electronic structural groups, is permitting a detailed investigation of the fundamental nature of potencies. The immobilisation of solvatochromic dyes on transparent membranes takes these investigations to a new level of investigative precision. Aims To attach as many different solvatochromic dyes as possible to triacetylcellulose membranes, and where successful, to observe in detail the spectroscopic changes that occur on exposure to potencies. Immobilisation of dyes onto membranes de-couples the initial dye-potency interaction from later aggregation processes, thereby allowing a host of questions to be asked about what exactly potencies are doing to solvatochromic dyes and in turn indicating what the identities of potencies are likely to be. Methodology A number of methods have been explored for covalently linking dyes to membranes, which at the same time maintain the integrity of the solvatochromic chromophore. Immobilised dyes, in contrast to dyes in solution, behave differently, which means water-insoluble dyes for instance, can be used under a range of solution conditions that were not possible previously. Results and discussion Results from three positively solvatochromic dyes show that potencies cause a bathochromic shift in their spectra, confirming what has been seen previously with encapsulated dyes but with greater clarity. Results can be explained by invoking a polarising effect of potencies and differential stabilisation of the dyes’ ground and excited electronic states. The kinetics of the dye-potency interaction indicate the effect of potency reaches a maximum and then declines. Conclusion Immobilisation of solvatochromic dyes presents a significant step forward in the ability to investigate homeopathic potencies at the physico-chemical level.
- Published
- 2021
65. Soluble trail has better efficacy than full-length membrane-bound trail, and in combination with akti blocks pro-metastatic cytokine production in prostate cancer cells
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Andrea Mohr, Ralf M. Zwacka, C. Tianyuan, and Greg N. Brooke
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Cancer Research ,Transplantation ,Membrane bound ,Chemistry ,medicine.medical_treatment ,Immunology ,Cell Biology ,medicine.disease ,Prostate cancer ,Cytokine ,Oncology ,medicine ,Cancer research ,Immunology and Allergy ,Genetics (clinical) - Published
- 2021
66. Can coacervation unify disparate hypotheses in the origin of cellular life?
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Rudrarup Bose, T-Y Dora Tang, and Basusree Ghosh
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Protocell ,0303 health sciences ,Coacervate ,Polymers and Plastics ,Membrane bound ,Chemistry ,Surfaces and Interfaces ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Cellular life ,03 medical and health sciences ,Colloid and Surface Chemistry ,Abiogenesis ,Biophysics ,Physical and Theoretical Chemistry ,030304 developmental biology - Abstract
Here, we review the recent progress in the characterisation and utilisation of coacervates as protocell models in origin of life studies. We provide evidence that coacervation could have played a unique role during the origin of life based on its ability to form from a range of different prebiotically relevant molecules; partition solutes and maintain the solute’s partition coefficient during enzymatic reactions; support and alter RNA catalysis and readily deform its shape. We discuss how these properties could have been important for the formation of the first membrane bound cells; supporting RNA-peptide evolution and primitive metabolism; and in replicating and proliferating by growth and division processes.
- Published
- 2021
67. Crystal Structure of Miner1: The Redox-active 2Fe-2S Protein Causative in Wolfram Syndrome 2
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Conlan, Andrea R., Axelrod, Herbert L., Cohen, Aina E., Abresch, Edward C., Zuris, John, Yee, David, Nechushtai, Rachel, Jennings, Patricia A., and Paddock, Mark L.
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MOLECULAR structure , *OXIDATION-reduction reaction , *GENETIC disorders , *SYNDROMES , *ENDOPLASMIC reticulum , *MITOCHONDRIAL membranes , *OXIDATIVE stress , *LONGEVITY , *PROTEINS - Abstract
Abstract: The endoplasmic reticulum protein Miner1 is essential for health and longevity. Mis-splicing of CISD2, which codes for Miner1, is causative in Wolfram Syndrome 2 (WFS2) resulting in early onset optic atrophy, diabetes mellitus, deafness and decreased lifespan. In knock-out studies, disruption of CISD2 leads to accelerated aging, blindness and muscle atrophy. In this work, we characterized the soluble region of human Miner1 and solved its crystal structure to a resolution of 2.1 Å (R-factor=17%). Although originally annotated as a zinc finger, we show that Miner1 is a homodimer harboring two redox-active 2Fe-2S clusters, indicating for the first time an association of a redox-active FeS protein with WFS2. Each 2Fe-2S cluster is bound by a rare Cys3-His motif within a 17 amino acid segment. Miner1 is the first functionally different protein that shares the NEET fold with its recently identified paralog mitoNEET, an outer mitochondrial membrane protein. We report the first measurement of the redox potentials (E m) of Miner1 and mitoNEET, showing that they are proton-coupled with E m ∼0 mV at pH 7.5. Changes in the pH sensitivity of their cluster stabilities are attributed to significant differences in the electrostatic distribution and surfaces between the two proteins. The structural and biophysical results are discussed in relation to possible roles of Miner1 in cellular Fe-S management and redox reactions. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
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68. The solute carrier (SLC) complement of the human genome: Phylogenetic classification reveals four major families
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Fredriksson, Robert, Nordström, Karl J.V., Stephansson, Olga, Hägglund, Maria G.A., and Schiöth, Helgi B.
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HUMAN genome , *NEUROTRANSMITTERS , *MEMBRANE proteins , *AMINO acids , *HIDDEN Markov models , *NUCLEOTIDE sequence - Abstract
Abstract: Solute carriers (SLCs) is the largest group of transporters, embracing transporters for inorganic ions, amino acids, neurotransmitters, sugars, purines and fatty acids among other substrates. We mined the finished assembly of the human genome using Hidden Markov Models (HMMs) obtaining a total of 384 unique SLC sequences. Detailed clustering and phylogenetic analysis of the entire SLC family showed that 15 of the families place into four large phylogenetic clusters with the largest containing eight SLC families, suggesting that many of the distinct families of SLCs have a common evolutionary origin. This study represents the first overall genomic roadmap of the SLCs providing large sequence sets and clarifies the phylogenetic relationships among the families of the second largest group of membrane proteins. [Copyright &y& Elsevier]
- Published
- 2008
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69. Characterization of Campylobacter concisus hemolysins.
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Istivan, Taghrid S., Smith, Stuart C., Fry, Benjamin N., and Coloe, Peter J.
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GENES , *CAMPYLOBACTER , *PATHOGENIC microorganisms , *DENTAL caries , *GASTROENTERITIS , *ESCHERICHIA coli , *CLONING - Abstract
Campylobacter concisus is an opportunistic pathogen commonly found in the human oral cavity. It has also been isolated from clinical sources including gastroenteritis cases. Both secreted and cell-associated hemolytic activities were detected in C. concisus strains isolated from children with gastroenteritis. The secreted hemolytic activity of C. concisus strains was labile and was detected in variable levels from fresh-culture filtrates only. In addition, another secreted hemolysin/cytotoxin with a molecular weight <10 kDa was detected in a single C. concisus strain (RCH 12). A C. concisus genomic library, constructed from strain RCH 3 in Escherichia coli XL1-Blue, was screened for hemolytic clones. Subcloning and sequence analysis of selected hemolytic clones identified ORFs for genes that enhance hemolytic activity but do not appear to be related to any known hemolysin genes found in Gram-negative bacteria. In a previous study, a stable cell-associated hemolysin was identified as an outer-membrane phospholipase A (OMPLA) encoded by the pldA gene. In this study, we report cloning of the pldA gene of the clinical strain C. concisus RCH 3 and the complementation of phospholipase A activity in an E. coli pldA mutant. [ABSTRACT FROM AUTHOR]
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- 2008
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70. Engineering secretable forms of chaperones for immune modulation and vaccine development
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Beachy, S.H., Kisailus, A.J., Repasky, E.A., Subjeck, J.R., Wang, X.Y., and Kazim, A.L.
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HEAT shock proteins , *CANCER cells , *IMMUNOREGULATION , *VACCINATION - Abstract
Abstract: Heat shock proteins are present in almost all intracellular compartments and serve by folding newly synthesized proteins, disassembling unstable proteins, and assisting in the transportation of proteins within the cell. Under certain circumstances they are also present on the cell surface, and can be shed or secreted into the extracellular environment. Although they possess many functional roles, their ability to stimulate innate and antigen-specific immunity have made them attractive candidates for vaccine development. Here, we review some of the approaches that have been used to genetically engineer molecular chaperones for their secretion from tumor cells or targeting them to the plasma membrane of such cells in order to promote anti-tumor responses. Treatment of tumor cells engineered to secrete or display chaperones may be of benefit, particularly in the area of cell-based vaccine development. [Copyright &y& Elsevier]
- Published
- 2007
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71. Template selection and refinement considerations for modelling aminergic GPCR-ligand complexes
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Angela M. Finch, Kaniz F. Urmi, and Renate Griffith
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Models, Molecular ,0301 basic medicine ,Protein Conformation ,Membrane bound ,Molecular Conformation ,Computational biology ,Molecular Dynamics Simulation ,Biology ,Ligands ,Homology (biology) ,Receptors, G-Protein-Coupled ,03 medical and health sciences ,Eticlopride ,Materials Chemistry ,Humans ,Amino Acid Sequence ,Amino Acids ,Physical and Theoretical Chemistry ,Receptor ,Spectroscopy ,5-HT receptor ,G protein-coupled receptor ,Binding Sites ,Sequence Homology, Amino Acid ,030102 biochemistry & molecular biology ,Computer Graphics and Computer-Aided Design ,Combinatorial chemistry ,Molecular Docking Simulation ,030104 developmental biology ,Template ,Docking (molecular) ,Protein Binding - Abstract
G protein-coupled receptors (GPCRs) are important targets for development of drugs for the treatment of many diseases. However, crystal structures are available for only a small fraction of these membrane bound proteins. Accurate homology models will provide opportunities for effective drug design targeting GPCRs. Recently, several serotonin receptor crystal structures were solved and needed to be evaluated as potential templates. In the first part of this work different measures of similarity in template selection were explored and methods for homology modelling, docking and refinement of aminergic GPCR-ligand complexes were developed and evaluated by comparing models of the D3-R/eticlopride complex with the crystal structure. Homology models of the three α1 adrenergic receptor subtypes and of a serotonin receptor subtype were then constructed using these methods These models were evaluated by docking a range of antagonists into them.
- Published
- 2017
72. Versatility of peroxisomes: An evolving concept
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Shirisha Nagotu and Rachayeeta Deb
- Subjects
0301 basic medicine ,Reactive oxygen species metabolism ,Membrane bound ,Computational biology ,Endoplasmic Reticulum ,03 medical and health sciences ,Human health ,Organelle ,Peroxisomes ,Animals ,Humans ,Cell Proliferation ,biology ,Endoplasmic reticulum ,Fatty Acids ,Cell Biology ,General Medicine ,Peroxisome ,biology.organism_classification ,Drosophila melanogaster ,030104 developmental biology ,Biochemistry ,Models, Animal ,Reactive Oxygen Species ,Oxidation-Reduction ,Biogenesis ,Developmental Biology - Abstract
Research spanning almost 50 years has highlighted unique characteristics and irreplaceable list of diverse functions performed by peroxisomes in various model systems. Peroxisomes are single membrane bound highly dynamic organelles ubiquitous to most eukaryotic cells. Proliferation by division of pre-existing organelles and the role of endoplasmic reticulum in the biogenesis of these organelles is now well established. The earliest identified conserved functions of peroxisomes are β-oxidation of fatty acids and reactive oxygen species metabolism. Several studies over the last few decades have reported the importance of this organelle and its numerous cell type, tissue and environment-dependent functions. Their role in several aspects of human health and disease is now under investigation. Studies related to peroxisome biology and functions are now also extended to diverse model systems like Drosophila melanogaster, trypanosomatids, etc. Peroxisomes also intricately collaborate and carry out these functions together with several other organelles in a cell. In this review, we aim to present an overview of our current knowledge of the repertoire of functions of peroxisomes in various model systems.
- Published
- 2017
73. Ultrasonication assisted ultrafast extraction of Tagetes erecta in water: cannonading antimicrobial, antioxidant components
- Author
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Judy Gopal, Sechul Chun, Doo Hwan Kim, and Zakayo Kazibwe
- Subjects
Antioxidant ,Membrane bound ,medicine.medical_treatment ,Sonication ,02 engineering and technology ,01 natural sciences ,Tagetes ,Materials Chemistry ,medicine ,Physical and Theoretical Chemistry ,Spectroscopy ,Chromatography ,biology ,Chemistry ,Organic solvent ,010401 analytical chemistry ,Extraction (chemistry) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Antimicrobial ,biology.organism_classification ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Hot water extraction ,0210 nano-technology - Abstract
Tagetes is one of the well established and well researched plant materials that are extensively used owing to their enumerable beneficial properties. Extraction of its bioactive components is well established in terms of organic solvent based extractions. However, organic solvent based extractions limit the practical applicability of the extracts and its practical implementation. In this regard, water based extraction strikes a high note. For the first time, the sonication assisted extraction of Tagetes has been demonstrated and the methodology validated for its superior extraction success compared to the conventional hot water extraction method. The results confirm the use of ultrasonication to lead to accelerated and extremely significant (2–3 order increase) extraction of total phenolics, antioxidants and flavanoids, leading to enhanced antimicrobial activity. The flowers held the highest bioactive molecules. FESEM based imaging studies revealed membrane bound damage as the reason behind the bactericidal activity. The future implementation of ultrasonication technology for accelerated ultrafast extraction of herbal and tea infusion formulations is highly recommended.
- Published
- 2017
74. Membrane-bound glycerol dehydrogenase catalyzes oxidation of D-pentonates to 4-keto-D-pentonates, D-fructose to 5-keto-D-fructose, and D-psicose to 5-keto-D-psicose
- Author
-
Roque Alberto Hours, Kazunobu Matsushita, Yoshitaka Ano, Yoshihiko Akakabe, Toshiharu Yakushi, Osao Adachi, and Naoya Kataoka
- Subjects
0106 biological sciences ,0301 basic medicine ,Psicose ,Gluconobacter ,Membrane bound ,viruses ,4-KETO-D-ARABONATE PRODUCTION ,Gluconobacter thailandicus ,INGENIERÍAS Y TECNOLOGÍAS ,Fructose ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biochemistry ,Biotecnología Industrial ,Analytical Chemistry ,4-keto-D-pentonate ,Absorbance ,03 medical and health sciences ,chemistry.chemical_compound ,4-keto-D-arabonate production ,010608 biotechnology ,Glycerol ,OXIDATIVE FERMENTATION ,Molecular Biology ,Ciencias Exactas ,chemistry.chemical_classification ,Glycerol dehydrogenase ,Cell Membrane ,Organic Chemistry ,D fructose ,4-KETO-D-PENTONATE ,Genomics ,General Medicine ,030104 developmental biology ,Enzyme ,Solubility ,chemistry ,ACETIC ACID BACTERIA ,Acetic acid bacteria ,Biocatalysis ,GLYCEROL DEHYDROGENASE ,Oxidative fermentation ,Oxidation-Reduction ,Sugar Alcohol Dehydrogenases ,Biotechnology - Abstract
A novel oxidation of D-pentonates to 4-keto-D-pentonates was analyzed with Gluconobacter Thailandicus NBRC 3258. D-Pentonate 4-dehydrogenase activity in the membrane fraction was readily inactivated by EDTA and it was reactivated by the addition of PQQ and Ca2+. D-Pentonate 4-dehydrogenase was purified to two different subunits, 80 and 14 kDa. The absorption spectrum of the purified enzyme showed no typical absorbance over the visible regions. The enzyme oxidized D-pentonates to 4-keto-D-pentonates at the optimum pH of 4.0. In addition, the enzyme oxidized D-fructose to 5-keto-D-fructose, D-psicose to 5-keto-D-psicose, including the other polyols such as, glycerol, D-ribitol, D-arabitol, and D-sorbitol. Thus, D-pentonate 4-dehydrogenase was found to be identical with glycerol dehydrogenase (GLDH), a major polyol dehydrogenase in Gluconobacter species. The reaction versatility of quinoprotein GLDH was notified in this study., Facultad de Ciencias Exactas, Centro de Investigación y Desarrollo en Fermentaciones Industriales
- Published
- 2017
75. Biosynthesis of UDP-xylose: characterization of membrane-bound At Uxs2.
- Author
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Pattathil, Sivakumar, Harper, April, and Bar-Peled, Maor
- Subjects
SUGAR ,BIOSYNTHESIS ,GLYCOPROTEINS ,POLYSACCHARIDES ,METABOLITES ,BIOCHEMISTRY - Abstract
UDP-xylose (UDP-Xyl) is a sugar donor for the synthesis of glycoproteins, polysaccharides, various metabolites, and oligosaccharides in plants, vertebrates, and fungi. In plants, the biosynthesis of UDP-Xyl from UDP-glucuronic acid (UDP-GlcA) appears to be catalyzed by numerous UDP-glucuronic acid decarboxylase (Uxs) isoforms. For example, six Uxs isoforms in Arabidopsis thaliana (L.) and four in rice have been identified. However, the reason/s for the existence of several isoforms that are necessary for the synthesis of UDP-Xyl remains unknown. Here, we describe a Uxs isoform in Arabidopsis, AtUXS2, encoding an integral membrane protein that appears to be localized to the Golgi apparatus. The enzyme is a dimer and has distinct properties. Unlike the UXS3 isoform, which is shown here to be a soluble protein, the UXS2 isoform is membrane bound. The characteristics of the membrane-bound AtUxs2 and cytosolic AtUxs3 support the hypothesis that unique UDP-GlcA-DCs possessing distinct sub-cellular localizations can spatially regulate specific xylosylation events in plant cells. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
76. Solvent Mapping Approach for Uncovering Cryptic Pockets in Membrane-Bound Proteins
- Author
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Jan K. Marzinek, Peter J. Bond, Jim Warwicker, and Lorena Zuzic
- Subjects
Solvent ,Chemistry ,Membrane bound ,Biophysics - Published
- 2020
77. Transcriptome- based analysis of the diversity of membrane-bound lectins in Baikal amphipods Eulimnogammarus sp. and the Holarctic amphipod Gammarus lacustris
- Author
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A. Dolgikh, Polina Drozdova, Y. A. Lubyaga, Anna Nazarova, and Maxim A. Timofeyev
- Subjects
Transcriptome ,Holarctic ,biology ,Membrane bound ,Zoology ,biology.organism_classification ,Gammarus lacustris ,Eulimnogammarus - Published
- 2020
78. Quantitation of repetitive epitopes in glycosaminoglycans immobilized on hydrophobic membranes treated with cationic detergents
- Author
-
Rosén, Madeleine, Edfors-Lilja, Inger, and Björnsson, Sven
- Subjects
- *
GLYCOSAMINOGLYCANS , *EPITOPES - Abstract
Glycosaminoglycans (GAGs) are linear carbohydrate polymers containing repetitive sequences of differently sulfated uronic acid and glycosamine residues that are recognized by antibodies raised against proteoglycans. We have developed a method to demonstrate such repetitive sequence motifs in isolated GAG chains immobilized on hydrophobic membranes derivatized with cationic detergents. Six monoclonal antibodies directed against Cs (2B6, 3B3, Cs56, and 1B5), Hs (HepSS), and Ks (5D4) were used to detect native and chondroitinase-generated epitopes in the immobilized GAGs. All antibodies, except 1B5, were able to detect epitopes in both proteoglycans and isolated GAGs. Type of detergent and buffer composition affected the accessibility and the retention of immobilized GAGs. The epitope density, i.e., the number of repetitive epitopes per GAG mass, was estimated as the ratio between antibody (epitope) and Alcian blue (mass) staining measured simultaneously. The epitope profiles, using six antibodies, were different for each sample (CsA, CsC, Ds, Hs, intact cartilage, and human serum). The epitope profile may be used as a structural characteristic of a GAG population. Electrophoretic separation of GAGs based on their glucuronic/ioduronic acid content and O-sulfate/N-sulfate ratio was performed using a diethylene glycol–diaminobutanol agarose gel. The electrophoretic populations were characterized by immunoblotting to detergent-treated membranes. [Copyright &y& Elsevier]
- Published
- 2002
79. The membrane-bound bile acid receptor (TGR5) controls the immune response against Listeria monocytogenes
- Author
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Verena Keitel, Dieter Häussinger, Pa Lang, and M Reich
- Subjects
Immune system ,Listeria monocytogenes ,Membrane bound ,Chemistry ,Immunology ,Gastroenterology ,medicine ,medicine.disease_cause ,G protein-coupled bile acid receptor ,Microbiology - Published
- 2016
80. Malignant ascites enhances migratory and invasive properties of ovarian cancer cells with membrane bound IL-6R in vitro
- Author
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Boyun Kim, Danny N. Dhanasekaran, Soochi Kim, Yong Sang Song, Hee Seung Kim, and Hye Ran Gwak
- Subjects
0301 basic medicine ,Time Factors ,endocrine system diseases ,Membrane bound ,IL-6R ,Carcinoma, Ovarian Epithelial ,migration ,Metastasis ,ascites ,0302 clinical medicine ,Cell Movement ,Ascites ,Ascitic Fluid ,Neoplasms, Glandular and Epithelial ,Phosphorylation ,Ovarian Neoplasms ,biology ,Middle Aged ,invasion ,female genital diseases and pregnancy complications ,3. Good health ,ovarian cancer ,Oncology ,030220 oncology & carcinogenesis ,Ovarian cancer cells ,Female ,RNA Interference ,medicine.symptom ,Research Paper ,Signal Transduction ,STAT3 Transcription Factor ,Epithelial-Mesenchymal Transition ,Antineoplastic Agents ,Transfection ,03 medical and health sciences ,Cell Line, Tumor ,medicine ,Humans ,Neoplasm Invasiveness ,Interleukin 6 ,Protein Kinase Inhibitors ,Aged ,Interleukin-6 ,business.industry ,Cell Membrane ,Cancer ,Janus Kinase 2 ,medicine.disease ,Antibodies, Neutralizing ,Receptors, Interleukin-6 ,eye diseases ,In vitro ,030104 developmental biology ,Immunology ,biology.protein ,Cancer research ,Ovarian cancer ,business - Abstract
// Soochi Kim 1, 2 , HyeRan Gwak 2, 3 , Hee Seung Kim 2, 4 , Boyun Kim 2, 5 , Danny N. Dhanasekaran 6 , Yong Sang Song 1, 2, 3, 4 1 Interdisciplinary Program in Cancer Biology, College of Medicine, Seoul National University, Seoul, Republic of Korea 2 Cancer Research Institute, Seoul National University, Seoul, Republic of Korea 3 Biomodulation, Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea 4 Department of Obstetrics and Gynecology, Seoul National University, Seoul, Republic of Korea 5 Nano System Institute, Seoul National University, Seoul, Korea 6 Stephenson Cancer Center, University of Oklahoma Health Sciences Center, USA Correspondence to: Yong Sang Song, email: yssong@snu.ac.kr Keywords: ascites, migration, invasion, IL-6R, ovarian cancer Received: April 18, 2016 Accepted: October 11, 2016 Published: November 4, 2016 ABSTRACT Transcoelomic route is the most common and the earliest route of metastasis, causing the ascites formation in advanced epithelial ovarian cancer (EOC). We demonstrated that interleukin 6 (IL-6) is enriched in the malignant ascites from patients with ovarian cancer, which enhanced invasive properties of EOC cells. Interestingly, the expression of IL-6R on cell membrane of EOC cells correlated with ascites-induced invasion. Selective knockdown of IL-6R or inhibition with IL-6 neutralizing antibody, suppressed the stimulatory effects of ascites on EOC invasion. Moreover, the ascites treatment induced the phosphorylation of JAK2-STAT3 and use of selective inhibitors of JAK2 and STAT3, blocked the expression of epithelial-mesenchymal transition related proteins in parallel with the suppression of EOC invasion. Thus, IL-6/IL-6R mediated JAK2-STAT3 signaling pathway could be a promising therapeutic target for anticancer therapy in ovarian cancer patients with ascites.
- Published
- 2016
81. Isolation, purification, and partial characterization of a membrane-bound Cl−/HCO3−-activated ATPase complex from rat brain with sensitivity to GABAAergic ligands
- Author
-
Sergey A. Menzikov
- Subjects
0301 basic medicine ,biology ,Membrane bound ,ATPase ,ATPase complex ,A protein ,General Medicine ,Rat brain ,Biochemistry ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Membrane ,biology.protein ,Atpase activity ,030217 neurology & neurosurgery ,Biotechnology - Abstract
This study describes the isolation and purification of a protein complex with -ATPase activity and sensitivity to GABAAergic ligands from rat brain plasma membranes. The ATPase complex was enriched...
- Published
- 2016
82. Detection of epitopes in glycosaminoglycans immobilized on hydrophobic membranes.
- Author
-
Björnsson, S.
- Subjects
- *
GLYCOSAMINOGLYCANS , *EPITOPES , *MONOCLONAL antibodies , *DERMATAN sulfate , *BIOLOGICAL membranes - Abstract
Glycosaminoglycans (GAGs) are linear carbohydrate polymers expressed on all cell surfaces, and bind growth factors that recognize specific disaccharide sequences. Such sequences in the GAG chain are not genetically determined but may be assembled by the cell in response to environmental changes. GAGs are strongly hydrophilic and negatively charged molecules that do not bind well to either polystyrene surfaces or to hydrophobic blotting membranes. Cationic detergents were used to derivatize hydrophobic membranes to become hydrophilic and positively charged. Binding of GAGs to derivatized membranes was optimized regarding pH and ionic strength. Five different monoclonal antibodies (Mab) were used to detect sequence epitopes in immobilized GAGs. Parallel samples were stained with Alcian Blue and the staining intensities were quantitated by scanning and densitometry. By calculating the ratio between the antibody staining (epitope) and Alcian Blue staining (mass), the epitope density, i.e. the number of repetitive epitopes per mass, is obtained. The epitope density with each antibody was different with different GAGs. Some epitopes were common in GAG, i.e. highly repetitive epitopes. Some epitopes were rare and possibly expressed only once per GAG molecule, i.e. low degree of repetition. An epitope density profile was obtained when each sample was stained with all antibodies and their epitope densities calculated at the plateau level. The epitope profile is an indirect measure of the sequence variability in GAGs. Determination of epitope density and profile can be used to characterize a GAG population and to discriminate between different populations with similar chemical composition. [ABSTRACT FROM AUTHOR]
- Published
- 2000
- Full Text
- View/download PDF
83. Fiber Formation from Liquid Crystalline Collagen Vesicles Isolated from Mussels
- Author
-
Matthew J. Harrington, Madelyn Clark, and Max Renner-Rao
- Subjects
Membrane bound ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Crystallinity ,Electrochemistry ,Animals ,General Materials Science ,Secretion ,Spectroscopy ,biology ,Chemistry ,Liquid crystalline ,Vesicle ,Surfaces and Interfaces ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,biology.organism_classification ,Secretory Vesicle ,Mytilus ,0104 chemical sciences ,Bivalvia ,Liquid Crystals ,Biophysics ,Electrophoresis, Polyacrylamide Gel ,Collagen ,0210 nano-technology - Abstract
Marine mussels (Mytilus edulis) fabricate byssal threads, high-performance biopolymeric fibers, which exhibit exceptional toughness and self-healing capacity. These properties are associated with collagenous proteins in the fibrous thread core known as preCols that self-organize into a hierarchical semicrystalline structure. Threads assemble individually in a bottom-up process lasting just minutes via secretion of membrane bound vesicles filled with preCols. However, very little is understood about the details and dynamics of this assembly process. Here, we explore the hypothesis that preCols are stored within the vesicles in a liquid crystalline phase, which contributes to fiber assembly by preordering molecules. To achieve this, a protocol was developed for extracting and isolating intact preCol secretory vesicles in high yield and purity. Vesicles were characterized and were manipulated in vitro, clearly indicating the dynamic liquid crystalline nature of the proteins within. Moreover, mechanical shear...
- Published
- 2019
84. Insights into membrane-bound presenilin 2 from all-atom molecular dynamics simulations
- Author
-
Ning Tang, Kasper Planeta Kepp, and Budheswar Dehury
- Subjects
Membrane bound ,PRESENILIN 2 ,Molecular Dynamics Simulation ,Presenilin ,Molecular dynamics ,presenilin 2 ,Structural Biology ,Alzheimer Disease ,mental disorders ,Presenilin-2 ,Presenilin-1 ,Humans ,Genetic risk ,skin and connective tissue diseases ,Molecular Biology ,membrane ,Chemistry ,Cryoelectron Microscopy ,Atom (order theory) ,General Medicine ,dynamics ,mutations ,nervous system diseases ,Membrane ,nervous system ,Chemical physics ,Amyloid Precursor Protein Secretases ,Alzheimer’s disease - Abstract
Presenilins 1 and 2 (PS1 or PS2) are main genetic risk factors of familial Alzheimer’s disease (AD) that produce the β-amyloid (Aβ) peptides and also have important stand-alone functions related to, e.g. calcium signaling. Most work so far has focused on PS1, but humans carry both PS1 and PS2, and mutations in both cause AD. Here, we develop a computational model of PS2 in the membrane to address the question how pathogenic PS2 mutations affect the membrane-embedded protein. The models are based on cryo-electron microscopy structures of PS1 translated to PS2, augmented with missing residues and a complete all-atom membrane–water system, and equilibrated using three independent 500-ns simulations of molecular dynamics with a structure-balanced force field. We show that the nine-transmembrane channel structure is substantially controlled by major dynamics in the hydrophilic loop bridging TM6 and TM7, which functions as a ‘plug’ in the PS2 membrane channel. TM2, TM6, TM7 and TM9 flexibility controls the size of this channel. We find that most pathogenic PS2 mutations significantly reduce stability relative to random mutations, using a statistical ANOVA test with all possible mutations in the affected sites as a control. The associated loss of compactness may also impair calcium affinity. Remarkably, similar properties of the open state are known to impair the binding of substrates to γ-secretase, and we thus argue that the two mechanisms could be functionally related. Communicated by Ramaswamy H. Sarma
- Published
- 2019
85. Decision letter: Obesity-linked suppression of membrane-bound O-acyltransferase 7 (MBOAT7) drives non-alcoholic fatty liver disease
- Author
-
Dennis E. Vance
- Subjects
medicine.medical_specialty ,Endocrinology ,Chemistry ,Membrane bound ,Internal medicine ,Acyltransferase ,Fatty liver ,medicine ,Non alcoholic ,Disease ,medicine.disease ,Obesity - Published
- 2019
86. Membrane order and ionic strength modulation of the inhibition of the membrane-bound acetylcholinesterase by epigallocatechin‑3‑gallate
- Author
-
Fernando Gabriel Dupuy, Alejandro de Athayde Moncorvo Collado, Paula Belén Salazar, and Carlos Minahk
- Subjects
0301 basic medicine ,Membrane bound ,Lipid Bilayers ,MEMBRANE INTERACTION ,Biophysics ,Biochemistry ,Catechin ,Ciencias Biológicas ,purl.org/becyt/ford/1 [https] ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Membrane interaction ,Spectroscopy, Fourier Transform Infrared ,Humans ,purl.org/becyt/ford/1.6 [https] ,Ions ,IONIC STRENGTH ,CHOLESTEROL ,Erythrocyte Membrane ,Osmolar Concentration ,Cell Biology ,Gallate ,Biofísica ,Acetylcholinesterase ,Kinetics ,030104 developmental biology ,Membrane ,Cholesterol ,Spectrometry, Fluorescence ,chemistry ,Solubility ,Ionic strength ,Salts ,Cholinesterase Inhibitors ,CIENCIAS NATURALES Y EXACTAS ,030217 neurology & neurosurgery - Abstract
In the present work, we analyzed how external factors can modulate the efficiency of epigallocatechin‑3‑O‑gallate (EGCG) inhibition of a membrane-bound isoform of the acetylcholinesterase. Increasing the ionic strength but not the osmolarity of the bulk medium proved to be an important factor. In addition, we verified a clear correlation between the inhibitory activity with the order degree of the membranes by using cholesterol-partially depleted red blood cell ghosts. These two factors i.e. high salt concentration in the bulk medium and less viscous membranes, allow a deeper insertion of the EGCG into the lipid bilayer, thus leading to a greater inhibition of AChE. As a corollary, we propose that any treatment or process that leads to a slight decrease in cholesterol content in the membranes can efficiently enhance the inhibitory activity of EGCG, which can have important consequences in all the pathologies where the inhibition of AChE is recommended. Fil: Salazar, Paula Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Dupuy, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: de Athayde Moncovo Collado, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Minahk, Carlos Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina
- Published
- 2019
87. CETSA beyond Soluble Targets: a Broad Application to Multipass Transmembrane Proteins
- Author
-
Michelle Schefter, Nils-Olov Hermansson, Arjan Snijder, Aarti Kawatkar, Andrew X. Zhang, Thomas Lundbäck, Niek Dekker, M. Paola Castaldi, and Dean G. Brown
- Subjects
0301 basic medicine ,Thermal shift assay ,Hot Temperature ,Membrane bound ,Pyridines ,Computational biology ,01 natural sciences ,Biochemistry ,Phase Transition ,Sarcoplasmic Reticulum Calcium-Transporting ATPases ,GABA Antagonists ,03 medical and health sciences ,GABA metabolism ,Receptors, GABA ,Cell Line, Tumor ,Humans ,Receptor, PAR-2 ,Benzodioxoles ,Benzyl Alcohols ,G protein-coupled receptor ,Benzodiazepinones ,010405 organic chemistry ,Chemistry ,Target engagement ,Imidazoles ,General Medicine ,Transmembrane protein ,0104 chemical sciences ,030104 developmental biology ,HEK293 Cells ,Membrane protein ,Benzamides ,Aminoquinolines ,Molecular Medicine ,Thapsigargin ,Benzimidazoles ,Biological Assay ,Protein Multimerization ,Target binding - Abstract
Demonstration of target binding is a key requirement for understanding the mode of action of new therapeutics. The cellular thermal shift assay (CETSA) has been introduced as a powerful label-free method to assess target engagement in physiological environments. Here, we present the application of live-cell CETSA to different classes of integral multipass transmembrane proteins using three case studies, the first showing a large and robust stabilization of the outer mitochondrial five-pass transmembrane protein TSPO, the second being a modest stabilization of SERCA2, and the last describing an atypical compound-driven stabilization of the GPCR PAR2. Our data demonstrated that using modified protocols with detergent extraction after the heating step, CETSA can reliably be applied to several membrane proteins of different complexity. By showing examples with distinct CETSA behaviors, we aim to provide the scientific community with an overview of different scenarios to expect during CETSA experiments, especially for challenging, membrane bound targets.
- Published
- 2019
88. Shaping membranes with disordered proteins
- Author
-
Mohammad Amin Abolghassemi Fakhree, Christian Blum, and Mireille M.A.E. Claessens
- Subjects
0301 basic medicine ,Disordered proteins ,Membrane bound ,Amino Acid Motifs ,Biophysics ,Membrane curvature ,Intrinsically disordered proteins ,Biochemistry ,Phase Transition ,03 medical and health sciences ,Membrane Lipids ,Protein structure ,Protein Domains ,Membrane domains ,Humans ,Molecular Biology ,Membranes ,030102 biochemistry & molecular biology ,Chemistry ,Membrane tethering ,Cell Membrane ,Membrane Proteins ,Intrinsically Disordered Proteins ,030104 developmental biology ,Membrane ,Membrane protein - Abstract
Membrane proteins control and shape membrane trafficking processes. The role of protein structure in shaping cellular membranes is well established. However, a significant fraction of membrane proteins is disordered or contains long disordered regions. It becomes more and more clear that these disordered regions contribute to the function of membrane proteins. While the fold of a structured protein is essential for its function, being disordered seems to be a crucial feature of membrane bound intrinsically disordered proteins and protein regions. Here we outline the motifs that encode function in disordered proteins and discuss how these functional motifs enable disordered proteins to modulate membrane properties. These changes in membrane properties facilitate and regulate membrane trafficking processes which are highly abundant in eukaryotes.
- Published
- 2019
89. Membrane-bound and soluble porcine CD83 functions antithetically in T cell activation and dendritic cell differentiation in vitro
- Author
-
Fengyang Wu, Yuzhu Zuo, Zhenyu Zhong, Fei Zhong, Jianlou Zhang, Shuang Liang, Dan Cui, Shanshan Huo, and Yonghong Zhang
- Subjects
0301 basic medicine ,Membrane bound ,Swine ,medicine.medical_treatment ,T cell ,T-Lymphocytes ,Immunology ,Immunoglobulins ,chemical and pharmacologic phenomena ,Dendritic cell differentiation ,Biology ,Lymphocyte Activation ,Peripheral blood mononuclear cell ,03 medical and health sciences ,0302 clinical medicine ,Antigens, CD ,medicine ,Animals ,Humans ,RNA, Small Interfering ,Cells, Cultured ,Glycoproteins ,Membrane Glycoproteins ,RNA ,hemic and immune systems ,Cell Differentiation ,Dendritic Cells ,In vitro ,Cell biology ,030104 developmental biology ,Cytokine ,medicine.anatomical_structure ,HEK293 Cells ,Leukocytes, Mononuclear ,Cytokines ,Function (biology) ,030215 immunology ,Developmental Biology - Abstract
Emerging evidence suggests that CD83, a dendritic cells (DCs) maturation marker in humans and mice, may prossess immunomodulatory capacities. Although porcine CD83 shares ∼75% sequence homology with its human counterpart, whether it functions as an immunoregulatory molecule remains unknown. To investigate porcine CD83 function, we deleted it in porcine DCs by RNA intereference. Results show that membrane-bound CD83 (mCD83) promotes DC-mediated T cell proliferation and cytokine production, thus confirming its immunoregulatory capacity. Intriguingly, porcine soluble CD83 (sCD83) treatment instead led to inhibition of DC-mediated T cell activation. Moreover, porcine sCD83 also inhibited differentiation of prepheral blood mononuclear cells (PBMCs) into DCs. These results collectively indicate that in addition to being a DC maturation maker, both membrane bound and souble porcine CD83 serve as immunoregulatory molecules with opposite effects on DC-mediated T cell activation and DC differentiation.
- Published
- 2019
90. Characterization of a Membrane‐Bound Insect Transferrin
- Author
-
Michelle Coca, Maureen J. Gorman, Diana G Najera, and Kayla E Nutsch
- Subjects
chemistry.chemical_classification ,Biochemistry ,Chemistry ,Transferrin ,Membrane bound ,media_common.quotation_subject ,Genetics ,Insect ,Molecular Biology ,Biotechnology ,media_common - Published
- 2019
91. Peer Review #1 of 'Two membrane-bound transcription factors regulate expression of various type-IV-pili surface structures in Sulfolobus acidocaldarius (v0.1)'
- Author
-
H Atomi
- Subjects
Sulfolobus acidocaldarius ,Chemistry ,Membrane bound ,Transcription factor ,Pilus ,Cell biology - Published
- 2019
92. Peer Review #2 of 'Two membrane-bound transcription factors regulate expression of various type-IV-pili surface structures in Sulfolobus acidocaldarius (v0.1)'
- Author
-
B Lee
- Subjects
Sulfolobus acidocaldarius ,Chemistry ,Membrane bound ,Transcription factor ,Pilus ,Cell biology - Published
- 2019
93. Transitions in filament geometry drive ESCRT-III-mediated membrane remodelling and fission
- Author
-
Andela Saric, Buzz Baum, and Lena Harker-Kirschneck
- Subjects
0303 health sciences ,Cell division ,Chemistry ,Membrane bound ,Fission ,Vesicle ,Geometry ,macromolecular substances ,ESCRT ,Protein filament ,03 medical and health sciences ,0302 clinical medicine ,Membrane ,Helix ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
ESCRT-III is an evolutionarily conserved membrane remodeling machinery that, with the Vps4 ATPase, forms filaments able to cut biological membranes from the cytosolic side. This activity of ESCRT-III is essential for the final stage of cell division in archaea and in many eukaryotes, the formation of vesicles, the creation of exosomes, the release of viruses such as HIV-1 and Ebola, and for the repair and sealing of cellular membranes. While there has been recent rapid progress in describing the biochemical and cell biology details of different ESCRT-III functions, we lack an understanding of the physical mechanism involved in ESCRT-III-mediated membrane remodelling. Here, through the development of coarse-grained molecular dynamic simulations, we present a minimal model that captures the ability of ESCRT-III to induce experimentally reported cases of ESCRT-III driven membrane sculpting, including the formation of cones and tubules, and membrane scission. This model suggests a universal physical mechanism of action, that differs from that of other cytoskeletal elements, whereby a change in the twist of membrane bound ESCRT-III filaments drives transitions between a flat spiral and a 3D helix to induce membrane deformation and scission. We expect the mechanistic principles revealed here to be useful in manipulating ESCRT-III-driven processes in cells and in guiding the engineering of synthetic membrane-sculpting systems.
- Published
- 2019
94. Molecular snapshots of dynamic membrane-bound metabolons
- Author
-
Jean-Etienne Bassard, Tomas Laursen, Institut de biologie moléculaire des plantes (IBMP), Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
0303 health sciences ,Membrane bound ,Chemistry ,030303 biophysics ,Supramolecular chemistry ,Intact protein ,03 medical and health sciences ,chemistry.chemical_compound ,Membrane ,Membrane protein ,Dhurrin ,Biophysics ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Metabolon ,ComputingMilieux_MISCELLANEOUS ,Nanodisc - Abstract
Numerous biosynthetic pathways have been shown to assemble at the surface of cellular membranes into efficient dynamic supramolecular assemblies termed metabolons. In response to environmental stimuli, metabolons assemble on-demand making them highly dynamic and fragile. This transient nature has previously hampered isolation and molecular characterization of dynamic metabolons. In contrast to conventional detergents, which tend to disrupt weak protein-protein interactions and remove lipids, the competence of a styrene maleic acid copolymer to carve out discrete lipid nanodisc from membranes offers immense potential for isolation of intact protein assemblies. Here, we present a method to extract the entire membrane-bound dhurrin pathway directly from microsomal fractions of the cereal Sorghum bicolor. This detergent-free nanodisc approach may be generally transposed for isolation of entire plant biosynthetic metabolons. This method provides a simple practical toolkit for the study of membrane protein complexes.
- Published
- 2019
95. 19F-Labeled amino acids for NMR structure analysis of membrane-bound peptides
- Author
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Sergii Afonin, Anne S. Ulrich, and Igor V. Komarov
- Subjects
chemistry.chemical_classification ,Structure analysis ,Membrane bound ,Chemistry ,Stereochemistry ,Molecule ,Amino acid residue ,Lipid bilayer ,Amino acid - Abstract
Solid-state 19F-NMR is a valuable tool in structural studies of membrane-associated peptides. Progress in this area became possible after successful design and synthesis of the fluorine-contained amino acids suitable to substitute natural amino acid residues in the peptides without compromising their structure and properties. These amino acids (labels) are incorporated into the molecules of the studied peptides and provide structural constraints for the labeled peptides embedded into oriented lipid bilayers under quasinatural conditions. The chapter overviews the literature on the design, synthesis, and validation of the labels. Recent examples of the label applications to study membrane-active peptides are given.
- Published
- 2019
96. Analysis of Toll-Like Receptors in Human Milk: Detection of Membrane-Bound and Soluble Forms
- Author
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Chiara Cattaneo, Diego Gazzolo, Miriam Sabatini, Marcello Manfredi, Maria Chiara Strozzi, Alice Caramaschi, Elena Uga, Maria Cavaletto, Michela Braghin, Chiara Peila, and Gianluca Cosi
- Subjects
0301 basic medicine ,lcsh:Immunologic diseases. Allergy ,Proteomics ,Article Subject ,Membrane bound ,Immunology ,Enzyme-Linked Immunosorbent Assay ,Biology ,Chemical Fractionation ,03 medical and health sciences ,0302 clinical medicine ,Tandem Mass Spectrometry ,medicine ,Immunology and Allergy ,Humans ,Amino Acid Sequence ,Receptor ,Mature milk ,Milk, Human ,Toll-Like Receptors ,Gestational age ,food and beverages ,General Medicine ,medicine.disease ,TLR2 ,030104 developmental biology ,030220 oncology & carcinogenesis ,TLR6 ,Necrotizing enterocolitis ,Colostrum ,Female ,lcsh:RC581-607 ,Biomarkers ,Research Article - Abstract
The bioactive and anti-inflammatory role of human milk components has been recognized; active milk components include soluble forms of Toll-like receptors (TLRs). Preterm babies are more susceptible to infections and may succumb to necrotizing enterocolitis (NEC), a gastrointestinal disease which is exacerbated by an excessive inflammatory response after TLR activation. Here, we investigated the presence of Toll-like receptors TLR1/2/4/6 in colostrum and mature milk of women who delivered before (preterm) or after (term) 37 weeks of gestational age, integrating classical immune-related techniques with proteomic LC-MS/MS analysis. We have detected immunoreactivity for TLRs mostly in preterm samples, even for TLR1 and TLR6, until now not described in human milk. We demonstrated the presence of only TLR2 in the milk fat globule membrane, while the immunoreactivity of TLR1/4/6 was ascribed to crossreaction with some interesting milk proteins sharing leucine-rich repeat domains. These results will provide new insights into the definition of the role of TLRs in intestinal immune regulation of the newborns.
- Published
- 2019
- Full Text
- View/download PDF
97. Method to Study Dynamics of Membrane-Bound Plant Transcription Factors During Biotic Interactions in Tomato
- Author
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Shrabani Basak, Payel Bhattacharjee, Shreya Chowdhury, Pallob Kundu, and Supriyo Chowdhury
- Subjects
0106 biological sciences ,0301 basic medicine ,Regulation of gene expression ,biology ,Membrane bound ,Chemistry ,Agrobacterium ,fungi ,Dynamics (mechanics) ,Biotic stress ,biology.organism_classification ,01 natural sciences ,Cell biology ,03 medical and health sciences ,Transformation (genetics) ,030104 developmental biology ,Transcription factor ,Gene ,010606 plant biology & botany - Abstract
Sequestration of a transcription factor in a cellular membrane and releasing it on demand is an additional layer of gene regulation that is considered a rapid mode to reprogram a gene expression cascade when a plasma membrane stress signal is perceived. Better understanding of the dynamic exchange of membrane-bound transcription factors (MTFs) during biotic stress requires the development of a simple, efficient, and quick assay system. Here we report an Agrobacterium-based transient transformation method to assay the localization of fluorescent protein-tagged MTFs in tomato leaf epidermal peels that are subsequently infected with a pathogenic fungus. Essentially, our method mimics natural infection and facilitates the realistic monitoring of MTF movement during activation of a signaling event.
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- 2019
98. Experimental Setup for a Diffusion Bioreactor to Isolate Unculturable Soil Bacteria
- Author
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Jaisoo Kim and Dhiraj Kumar Chaudhary
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Soil bacteria ,biology ,Membrane bound ,Strategy and Management ,Mechanical Engineering ,Normal laboratory ,Metals and Alloys ,biology.organism_classification ,Industrial and Manufacturing Engineering ,Functional diversity ,Uncultured bacteria ,Methods Article ,Bioreactor ,Biochemical engineering ,Bacteria - Abstract
Unculturable bacteria are those bacteria which proliferate in their native habitat but unable to grow or thrive in the normal laboratory media and conditions. The molecular techniques have revealed the significance of these uncultured bacteria in terms of their functional diversity and potential to produce secondary metabolites. To achieve these benefits, scientists have attempted to isolate and cultivate unculturable bacteria in the laboratory using transwell plates, optical tweezers, laser microdissection, microbioreactors, and diffusions bioreactors. However, these techniques are still inadequate to resolve the difficulties of cultivating unculturable bacteria. Therefore, it is essential to develop new cultivation method that enables growth of diverse range of bacteria in the laboratory conditions. Diffusion bioreactor is a membrane bound chamber which allows microbes to proliferate in their native environment by providing the excess to naturally occurring nutrients and signaling compounds. This paper presents efficient and reliable protocol to construct a diffusion bioreactor and its utilization to isolate and cultivate unculturable soil bacteria in laboratory.
- Published
- 2019
99. Obtaining of NK cell clones using IL-2 and gene-modified K562 cells expressing membrane-bound IL-21 v1
- Author
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Maria Streltsova, Sofya Erokhina, Leonid Kanevskiy, Dean Lee, William Telford, and Elena Kovalenko
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medicine.anatomical_structure ,Membrane bound ,Chemistry ,Cell ,medicine ,Gene ,Molecular biology ,K562 cells - Abstract
Here we present the simple and effective method for obtaining clones of NK cells, sorted according to a given set of surface markers. The lifespan of clones grown by this method can reach 14 weeks and cloning efficiency is up to 50%, depending on the original NK cell subset. Obtained clones are functionally active; they are able to lyse target cells and produce IFNγ. The principle of method includes single cell sorting and further clonal expansion in the presence of IL-2 and gene-modified K562 feeder cells. Our method allows to expand the progeny of a single NK cell up to 10-20×106 NK cells suitable to study phenotype, proliferative and functional activity of a certain NK cell clone. The work was supported by Russian Science Foundation, grant #16-15-00309.
- Published
- 2018
100. Recurrent Stimulation of NK Cell Clones with K562 Expressing Membrane-Bound IL-21 Affects Their Phenotype, IFN-γ Production and Lifespan
- Author
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William G. Telford, Maria A. Streltsova, Dean A. Lee, Maria V. Grechikhina, Elena I. Kovalenko, Leonid M. Kanevskiy, Sofya A. Erokhina, and Alexander M. Sapozhnikov
- Subjects
immunology ,medicine.anatomical_structure ,Chemistry ,Membrane bound ,Cell ,medicine ,Stimulation ,Phenotype ,K562 cells ,Cell biology - Abstract
A pattern of NK cell heterogeneity in each individual determines proliferative and functional responses of NK cells to activating stimuli. Obtaining the progeny of a single cell by cloning original population is one of the ways to study the NK cell heterogeneity. In this work, we used single cell sorting into a plate and stimulation by IL-2 and gene-modified K562 feeder cells expressing membrane-bound IL-21 (K562-mbIL21) that led to generation of phenotypically confirmed and functionally active NK cell clones. We applied two models of clone cultivation, which differently affected their phenotype, lifespan and functional activity. The first model, which included weekly restimulation of clones with K562-mbIL21 and IL-2, resulted in the generation of relatively short-lived (5-7 weeks) clones of highly activated NK cells. HLA-DR expression in the expanded NK cells correlated strongly with IFN-γ production. The second model, in which NK cells were restimulated mainly with IL-2 alone, produced long-lived clones (8-14 weeks) that expanded up to 107 cells with lower ability to produce IFN-γ. Our method is applicable for studying variability in phenotype, proliferative and functional activity of the certain NK cell progeny in response to the stimulation, which may help in selecting NK cells best suited for clinical use.
- Published
- 2018
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