Molecular mechanisms underlying the promotion of wound repair by coenzyme Q10: PI3K/Akt signal activation via alterations to cell membrane domains

The molecular mechanisms of αvβ3 integrin affinity regulation have important biological implications in tumour development, wound repair and angiogenesis. We expressed, purified and characterized recombinant forms of human αvβ3 (r-αvβ3) and compared the activation state of these with αvβ3 in its cellular environment. The ligand specificity and selectivity of recombinant full-length and double transmembrane truncations of r-αvβ3 cloned in BacPAK6 vectors and expressed in Sf9 and High Five insect cells were compared with those of native placental αvβ3 and the receptor in situ on the cell surface. r-αvβ3 integrins were purified by affinity chromatography from detergent extracts of cells (full-length), and from the culture medium of cells expressing double-truncated r-αvβ3. r-αvβ3 had the same epitopes, ligand-binding specificities, bivalent cation requirements and susceptibility to RGD-containing peptides as native αvβ3. On M21-L4 melanoma cells, αvβ3 mediated binding to vitronectin, but not to fibrinogen unless activated with Mn2+. Non-activated αIIbβ3 integrin as control in M21-L-IIb cells had the opposite profile, mediating binding to fibrinogen, but not to vitronectin unless activated with Mn2+. Thus these receptors had moderate to low ligand affinity. In marked contrast, purified αvβ3 receptors, with or without transmembrane and cytoplasmic domains, were constitutively of high affinity and able to bind strongly to vitronectin, fibronectin and fibrinogen under physiological conditions. Our data suggest that, in contrast with the positive regulation of αIIbβ3 in situ, intracellular controls lower the affinity of αvβ3, and the cytoplasmic domains may act as a target for negative regulators of αvβ3 activity.

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Research progress on the antibacterial mechanisms of carvacrol: a mini review

Bioactive Compounds in Health and Disease ◽

10.31989/bchd.v1i6.551 ◽

2018 ◽

Vol 1 (6) ◽

pp. 71

Author(s):

Dan Zhang ◽

Ren-You Gan ◽

Ying-Ying Ge ◽

Qiong-Qiong Yang ◽

Jiao Ge ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Antibacterial Activity ◽

Quorum Sensing ◽

Cell Membrane ◽

Molecular Mechanisms ◽

Food Preservation ◽

Research Progress ◽

Oxygen Species ◽

Aromatic Plants ◽

Volatile Oils

Background: Carvacrol is an aromatic phenolic terpenoid widely existing in the volatile oils of thyme, oregano, and some other aromatic plants. Recent studies have found that carvacrol possesses excellent antibacterial activity. In order to provide an updated information about the antibacterial potentials of carvacrol, herein, we summarized recent publications about the antibacterial activity of carvacrol, with special attention paid to its antibacterial molecular mechanisms, including desrupting cell membrane, depleting intracellular ATP, inducing reactive oxygen species, inhibiting efflux pumps, as well as suppressing two important virulence factors, biofilm and quorum sensing. In conclusion, carvacrol is a promising natural antibacterial compound with potential application in food preservation and infection.Keywords：Carvacrol, antibacterial mechanisms, biofilm, quorum sensing

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POSTERS. The cellular and molecular mechanisms of amnion wound repair

Journal of Anatomy ◽

10.1046/j.1469-7580.2001.1991021723.x ◽

2001 ◽

Vol 199 (1) ◽

pp. 217-227

Author(s):

J. M. MOORE ◽

K. C. McCULLOGH ◽

D. J. WILSON

Keyword(s):

Wound Repair ◽

Molecular Mechanisms

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Molecular mechanisms underlying the effects of cholesterol on neuronal cell membrane function and drug-membrane interactions.

Lipids, health, and behavior. ◽

10.1037/10259-007 ◽

1997 ◽

pp. 127-138 ◽

Cited By ~ 1

Author(s):

R. Preston Mason

Keyword(s):

Cell Membrane ◽

Molecular Mechanisms ◽

Neuronal Cell ◽

Membrane Interactions ◽

Membrane Function

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Structural Similarity with Cholesterol Reveals Crucial Insights into Mechanisms Sustaining the Immunomodulatory Activity of the Mycotoxin Alternariol

Cells ◽

10.3390/cells9040847 ◽

2020 ◽

Vol 9 (4) ◽

pp. 847 ◽

Cited By ~ 3

Author(s):

Giorgia Del Favero ◽

Raphaela M. Mayer ◽

Luca Dellafiora ◽

Lukas Janker ◽

Laura Niederstaetter ◽

...

Keyword(s):

Molecular Mechanisms ◽

Structural Similarity ◽

Immunomodulatory Activity ◽

Continuous Exposure ◽

Membrane Domains ◽

Toll Like Receptor ◽

Caveolin 1 ◽

Domestic Environments ◽

Opening Up ◽

Immunomodulatory Potential

The proliferation of molds in domestic environments can lead to uncontrolled continuous exposure to mycotoxins. Even if not immediately symptomatic, this may result in chronic effects, such as, for instance, immunosuppression or allergenic promotion. Alternariol (AOH) is one of the most abundant mycotoxins produced by Alternaria alternata fungi, proliferating among others in fridges, as well as in humid walls. AOH was previously reported to have immunomodulatory potential. However, molecular mechanisms sustaining this effect remained elusive. In differentiated THP-1 macrophages, AOH hardly altered the secretion of pro-inflammatory mediators when co-incubated with lipopolysaccharide (LPS), opening up the possibility that the immunosuppressive potential of the toxin could be related to an alteration of a downstream pro-inflammatory signaling cascade. Intriguingly, the mycotoxin affected the membrane fluidity in macrophages and it synergistically reacted with the cholesterol binding agent MβCD. In silico modelling revealed the potential of the mycotoxin to intercalate in cholesterol-rich membrane domains, like caveolae, and immunofluorescence showed the modified interplay of caveolin-1 with Toll-like Receptor (TLR) 4. In conclusion, we identified the structural similarity with cholesterol as one of the key determinants of the immunomodulatory potential of AOH.

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Pharmacological Overview of the BGP-15 Chemical Agent as a New Drug Candidate for the Treatment of Symptoms of Metabolic Syndrome

Molecules ◽

10.3390/molecules25020429 ◽

2020 ◽

Vol 25 (2) ◽

pp. 429

Author(s):

Ágota Pető ◽

Dóra Kósa ◽

Pálma Fehér ◽

Zoltán Ujhelyi ◽

Dávid Sinka ◽

...

Keyword(s):

Molecular Mechanisms ◽

Parp Inhibitor ◽

Drug Candidate ◽

Chemical Agent ◽

Membrane Domains ◽

Protective Effects ◽

Pharmacological Effects ◽

Research Groups ◽

Insulin Sensitizer ◽

Beneficial Effects

BGP-15 is a new insulin sensitizer drug candidate, which was developed by Hungarian researchers. In recent years, numerous research groups have studied its beneficial effects. It is effective in the treatment of insulin resistance and it has protective effects in Duchenne muscular dystrophy, diastolic dysfunction, tachycardia, heart failure, and atrial fibrillation, and it can alleviate cardiotoxicity. BGP-15 exhibits chemoprotective properties in different cytostatic therapies, and has also proven to be photoprotective. It can additionally have advantageous effects in mitochondrial-stress-related diseases. Although the precise mechanism of the effect is still unknown to us, we know that the molecule is a PARP inhibitor, chaperone co-inducer, reduces ROS production, and is able to remodel the organization of cholesterol-rich membrane domains. In the following review, our aim was to summarize the investigated molecular mechanisms and pharmacological effects of this potential API. The main objective was to present the wide pharmacological potentials of this chemical agent.

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Targeting and Stability of Na/Ca Exchanger 1 in Cardiomyocytes Requires Direct Interaction with the Membrane Adaptor Ankyrin-B

Journal of Biological Chemistry ◽

10.1074/jbc.m607096200 ◽

2006 ◽

Vol 282 (7) ◽

pp. 4875-4883 ◽

Cited By ~ 48

Author(s):

Shane R. Cunha ◽

Naina Bhasin ◽

Peter J. Mohler

Keyword(s):

Molecular Mechanisms ◽

Cardiac Tissue ◽

Direct Interaction ◽

Binding Activity ◽

Membrane Domains ◽

Excitable Cells ◽

Expression Activity ◽

Cellular Pathways ◽

Ankyrin B ◽

Calcium Extrusion

Na/Ca exchanger activity is important for calcium extrusion from the cardiomyocyte cytosol during repolarization. Animal models exhibiting altered Na/Ca exchanger expression display abnormal cardiac phenotypes. In humans, elevated Na/Ca exchanger expression/activity is linked with pathophysiological conditions including arrhythmia and heart failure. Whereas the molecular mechanisms underlying Na/Ca exchanger biophysical properties are widely studied and generally well characterized, the cellular pathways and molecular partners underlying the specialized membrane localization of Na/Ca exchanger in cardiac tissue are essentially unknown. In this report, we present the first direct evidence for a protein pathway required for Na/Ca exchanger localization and stability in primary cardiomyocytes. We define the minimal structural requirements on ankyrin-B for direct Na/Ca exchanger interactions. Moreover, using ankyrin-B mutants that lack Na/Ca exchanger binding activity, and primary cardiomyocytes with reduced ankyrin-B expression, we demonstrate that direct interaction with the membrane adaptor ankyrin-B is required for the localization and post-translational stability of Na/Ca exchanger 1 in neonatal mouse cardiomyocytes. These results raise exciting new questions regarding potentially dynamic roles for ankyrin proteins in the biogenesis and maintenance of specialized membrane domains in excitable cells.

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The Molecular Basis of Phospholipase D2-Induced Chemotaxis: Elucidation of Differential Pathways in Macrophages and Fibroblasts

Molecular and Cellular Biology ◽

10.1128/mcb.00229-10 ◽

2010 ◽

Vol 30 (18) ◽

pp. 4492-4506 ◽

Cited By ~ 27

Author(s):

Katie Knapek ◽

Kathleen Frondorf ◽

Jennalee Post ◽

Stephen Short ◽

Dianne Cox ◽

...

Keyword(s):

Immune Response ◽

Cell Migration ◽

Growth Factor ◽

Cell Line ◽

Protein Interactions ◽

Wound Repair ◽

Molecular Mechanisms ◽

Growth Factor Receptor ◽

Cell Transfection ◽

Phospholipase D1

ABSTRACT We report the molecular mechanisms that underlie chemotaxis of macrophages and cell migration of fibroblasts, cells that are essential during the body's innate immune response and during wound repair, respectively. Silencing of phospholipase D1 (PLD1) and PLD2 reduced cell migration (both chemokinesis and chemotaxis) by ∼60% and >80%, respectively; this migration was restored by cell transfection with PLD2 constructs refractory to small interfering RNA (siRNA). Cells overexpressing active phospholipase D1 (PLD1) but, mostly, active PLD2 exhibited cell migration capabilities that were elevated over those elicited by chemoattractants alone. The mechanism for this enhancement is complex. It involves two pathways: one that is dependent on the activity of the lipase (and signals through its product, phosphatidic acid [PA]) and another that involves protein-protein interactions. The first is evidenced by partial abrogation of chemotaxis with lipase activity-defective constructs (PLD2-K758R) and by n-butanol treatment of cells. The second is evidenced by PLD association with the growth factor receptor-bound protein 2 (Grb2) through residue Y169, located within a Src homology 2 (SH2) consensus site. The association Grb2-PLD2 could be visualized by fluorescence microscopy in RAW/LR5 macrophages concentrated in actin-rich membrane ruffles, making possible that Grb2 serves as a docking or intermediary protein. The Grb2/PLD2-mediated chemotaxis process also depends on Grb2's ability to recognize other motility proteins, like the Wiskott-Aldrich syndrome protein (WASP). Cell transfection with WASP, PLD2, and Grb2 constructs yields the highest levels of cell migration response, particularly in a macrophage cell line (RAW/LR5) and only modestly in the fibroblast cell line COS-7. Further, RAW/LR5 macrophages utilize for cell migration an additional pathway that involves S6 kinase (S6K) through PLD2-Y296, known to be phosphorylated by epidermal growth factor receptor (EGFR) kinase. Thus, both fibroblasts and macrophages use activity-dependent and activity-independent signaling mechanisms. However, highly mobile cells like macrophages use all signaling machinery available to them to accomplish their required function in rapid immune response, which sets them apart from fibroblasts, cells normally nonmobile that are only briefly involved in wound healing.

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Control of lipid domain organization by a biomimetic contractile actomyosin cortex

eLife ◽

10.7554/elife.24350 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 26

Author(s):

Sven Kenjiro Vogel ◽

Ferdinand Greiss ◽

Alena Khmelinskaia ◽

Petra Schwille

Keyword(s):

Cell Membrane ◽

Actin Filaments ◽

Shape Change ◽

Line Tension ◽

Membrane Domains ◽

Lipid Domain ◽

Actin Cortex ◽

Control Dynamic ◽

Underlying Mechanisms ◽

Lateral Organization

The cell membrane is a heterogeneously organized composite with lipid-protein micro-domains. The contractile actin cortex may govern the lateral organization of these domains in the cell membrane, yet the underlying mechanisms are not known. We recently reconstituted minimal actin cortices (MACs) (Vogel et al., 2013b) and here advanced our assay to investigate effects of rearranging actin filaments on the lateral membrane organization by introducing various phase-separated lipid mono- and bilayers to the MACs. The addition of actin filaments reorganized membrane domains. We found that the process reached a steady state where line tension and lateral crowding balanced. Moreover, the phase boundary allowed myosin driven actin filament rearrangements to actively move individual lipid domains, often accompanied by their shape change, fusion or splitting. Our findings illustrate how actin cortex remodeling in cells may control dynamic rearrangements of lipids and other molecules inside domains without directly binding to actin filaments.

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Myosin 10 and a Cytoneme-Localized Ligand Complex Promote Morphogen Transport

10.1101/2020.05.06.080820 ◽

2020 ◽

Author(s):

Eric T. Hall ◽

Daniel P. Stewart ◽

Miriam Dillard ◽

Ben Wagner ◽

April Sykes ◽

...

Keyword(s):

Cell Fate ◽

Sonic Hedgehog ◽

Molecular Mechanisms ◽

Transport Model ◽

Receptor Function ◽

Ligand Complex ◽

Signal Response ◽

Actin Motor ◽

Morphogen Transport ◽

Signal Activation

SummaryMorphogens function in concentration-dependent manners to instruct cell fate during tissue patterning. Molecular mechanisms by which these signaling gradients are established and reinforced remain enigmatic. The cytoneme transport model posits that specialized filopodia extend between morphogen-sending and responding cells to ensure that appropriate signal activation thresholds are achieved across developing tissues. How morphogens are transported along and deployed from cytonemes is not known. Herein we show that the actin motor Myosin 10 promotes cytoneme-based transport of Sonic Hedgehog (SHH) morphogen to filopodial tips, and that SHH movement within cytonemes occurs by vesicular transport. We demonstrate that cytoneme-mediated deposition of SHH onto receiving cells induces a rapid signal response, and that SHH cytonemes are promoted by a complex containing a ligand-specific deployment protein and associated co-receptor.One-Sentence summaryCytoneme-based delivery of the Sonic Hedgehog activation signal is promoted by Myosin 10 and BOC/CDON co-receptor function.

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