scholarly journals RhoB controls endothelial barrier recovery by inhibiting Rac1 trafficking to the cell border

2016 ◽  
Vol 213 (3) ◽  
pp. 385-402 ◽  
Author(s):  
Beatriz Marcos-Ramiro ◽  
Diego García-Weber ◽  
Susana Barroso ◽  
Jorge Feito ◽  
María C. Ortega ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Rho Gtpase ◽  
Inflammatory Diseases ◽  
Endothelial Barrier ◽  
Endosomal Trafficking ◽  
Barrier Dysfunction ◽  
Cell Border ◽  
Rac1 Activity ◽  
Endothelial Barriers ◽  
Specific Regulation

Endothelial barrier dysfunction underlies chronic inflammatory diseases. In searching for new proteins essential to the human endothelial inflammatory response, we have found that the endosomal GTPase RhoB is up-regulated in response to inflammatory cytokines and expressed in the endothelium of some chronically inflamed tissues. We show that although RhoB and the related RhoA and RhoC play additive and redundant roles in various aspects of endothelial barrier function, RhoB specifically inhibits barrier restoration after acute cell contraction by preventing plasma membrane extension. During barrier restoration, RhoB trafficking is induced between vesicles containing RhoB nanoclusters and plasma membrane protrusions. The Rho GTPase Rac1 controls membrane spreading and stabilizes endothelial barriers. We show that RhoB colocalizes with Rac1 in endosomes and inhibits Rac1 activity and trafficking to the cell border during barrier recovery. Inhibition of endosomal trafficking impairs barrier reformation, whereas induction of Rac1 translocation to the plasma membrane accelerates it. Therefore, RhoB-specific regulation of Rac1 trafficking controls endothelial barrier integrity during inflammation.

scholarly journals Driving Rho GTPase activity in endothelial cells regulates barrier integrity

2010 ◽  
Vol 103 (01) ◽  
pp. 40-55 ◽  
Author(s):  
Cora Beckers ◽  
Victor van Hinsbergh ◽  
Geerten van Nieuw Amerongen
Keyword(s):  
Barrier Function ◽  
Rho Gtpases ◽  
Rho Gtpase ◽  
Three Dimensional ◽  
Regulatory Proteins ◽  
Endothelial Barrier ◽  
Endothelial Barrier Function ◽  
Barrier Dysfunction ◽  
Gtpase Activation ◽  
The Individual

SummaryIn the past decade understanding of the role of the Rho GTPases RhoA, Rac1 and Cdc42 has been developed from regulatory proteins that regulate specific actin cytoskeletal structures – stress fibers, lamellipodia and filopodia – to complex integrators of cytoskeletal structures that can exert multiple functions depending on the cellular context. Fundamental to these functions are three-dimensional complexes between the individual Rho GTPases, their specific activators (GEFs) and inhibitors (GDIs and GAPs), which greatly outnumber the Rho GTPases themselves, and additional regulatory proteins. By this complexity of regulation different vasoactive mediators can induce various cytoskeletal structures that enable the endothelial cell (EC) to respond adequately. In this review we have focused on this complexity and the consequences of Rho GTPase regulation for endothelial barrier function. The permeability inducers thrombin and VEGF are presented as examples of G-protein coupled receptor- and tyrosine kinase receptormediated Rho GTPase activation, respectively. These mediators induce complex but markedly different networks of activators, inhibitors and effectors of Rho GTPases, which alter the endothelial barrier function. An interesting feature in this regulation is that Rho GTPases often have both barrier-protecting and barrier-disturbing functions. While Rac1 enforces the endothelial junctions, it becomes part of a barrier-disturbing mechanism as activator of reactive oxygen species generating NADPH oxidase. Similarly RhoA is protective under basal conditions, but becomes involved in barrier dysfunction after activation of ECs by thrombin. The challenge and promise lies in unfolding this complex regulation, as this will provide leads for new therapeutic opportunities.

scholarly journals Rap1 Spatially Controls ArhGAP29 To Inhibit Rho Signaling during Endothelial Barrier Regulation

2015 ◽  
Vol 35 (14) ◽  
pp. 2495-2502 ◽  
Author(s):  
A. Post ◽  
W. J. Pannekoek ◽  
B. Ponsioen ◽  
M. J. Vliem ◽  
J. L. Bos
Keyword(s):  
Plasma Membrane ◽  
Barrier Function ◽  
Rho Gtpase ◽  
Small Gtpase ◽  
Endothelial Barrier ◽  
Nucleotide Exchange ◽  
Endothelial Barrier Function ◽  
Nucleotide Exchange Factor ◽  
Barrier Regulation ◽  
Spatiotemporal Control

The small GTPase Rap1 controls the actin cytoskeleton by regulating Rho GTPase signaling. We recently established that the Rap1 effectors Radil and Rasip1, together with the Rho GTPase activating protein ArhGAP29, mediate Rap1-induced inhibition of Rho signaling in the processes of epithelial cell spreading and endothelial barrier function. Here, we show that Rap1 induces the independent translocations of Rasip1 and a Radil-ArhGAP29 complex to the plasma membrane. This results in the formation of a multimeric protein complex required for Rap1-induced inhibition of Rho signaling and increased endothelial barrier function. Together with the previously reported spatiotemporal control of the Rap guanine nucleotide exchange factor Epac1, these findings elucidate a signaling pathway for spatiotemporal control of Rho signaling that operates by successive protein translocations to and complex formation at the plasma membrane.

Abstract 132: Endothelial Progenitor Cells Prevent Endothelial Barrier Injury by Cdc42-dependent Assembly of VE-cadherin

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Hiroshi Ohkawra ◽  
Yidan D. Zhao ◽  
Asrar B. Malik
Keyword(s):  
Progenitor Cells ◽  
Endothelial Progenitor Cells ◽  
Barrier Function ◽  
Inflammatory Diseases ◽  
Vascular Inflammation ◽  
Endothelial Permeability ◽  
Endothelial Barrier ◽  
Endothelial Barrier Function ◽  
Barrier Dysfunction ◽  
Endothelial Progenitor

We investigated the use of bone-marrow derived endothelial progenitor cells (EPCs) for the treatment of microvascular endothelial injury caused by inflammatory diseases. As activation of the monomeric RhoGTPase Cdc42 signals annealing of adherens junctions (AJs) in the endothelial barrier, we examined the possibility that EPCs could restore endothelial barrier dysfunction by promoting Cdc42 activation in endothelial cells (ECs). We observed that co-culture of EPCs with ECs prevented the decrease in transendothelial electrical resistance (TER), a measure of AJ assembly, and the decrease in VE-cadherin expression induced by thrombin (4 U/mL). EPCs also significantly reduced the formation of inter-endothelial gaps mediated by RhoA activation as well as myosin light chain phosphorylation in response to thrombin. We showed that EPCs induced activation of Cdc42 in ECs and increased TER within 15 min after the addition EPCs to ECs, indicating the enhancement of endothelial barrier function. Addition of EPCs after thrombin-induced disruption of AJs also promoted rapid recovery of TER compared to controls. Based on siRNA knockdown data, the endothelial barrier protective effect of EPCs was mediated by Cdc42 activation in ECs. Thus, EPC-mediated activation of Cdc42 in ECs decreases basal endothelial permeability and prevents endothelial hyper-permeability induced by the mediator thrombin. EPC/EC cross-talk is a critical mechanism regulating endothelial barrier function suggesting the value of EPCs in the treatment of microvascular injury associated with vascular inflammation.

Role of Exosomes in the Exchange of Spermatozoa after Leaving the Seminiferous Tubule: A Review

2020 ◽  
Vol 21 (5) ◽  
pp. 330-338
Author(s):  
Luming Wu ◽  
Yuan Ding ◽  
Shiqiang Han ◽  
Yiqing Wang
Keyword(s):  
Drug Delivery ◽  
Plasma Membrane ◽  
Seminiferous Tubule ◽  
Metabolic Diseases ◽  
Inflammatory Diseases ◽  
Multivesicular Bodies ◽  
Extensive Search ◽  
Neurological Research ◽  
The One

Background: Exosomes are extracellular vesicles (EVs) released from cells upon fusion of an intermediate endocytic compartment with the plasma membrane. They refer to the intraluminal vesicles released from the fusion of multivesicular bodies with the plasma membrane. The contents and number of exosomes are related to diseases such as metabolic diseases, cancer and inflammatory diseases. Exosomes have been used in neurological research as a drug delivery tool and also as biomarkers for diseases. Recently, exosomes were observed in the seminal plasma of the one who is asthenozoospermia, which can affect sperm motility and capacitation. Objective: The main objective of this review is to deeply discuss the role of exosomes in spermatozoa after leaving the seminiferous tubule. Methods: We conducted an extensive search of the literature available on relationships between exosomes and exosomes in spermatozoa on the bibliographic database. Conclusion: : This review thoroughly discussed the role that exosomes play in the exchange of spermatozoa after leaving the seminiferous tubule and its potential as a drug delivery tool and biomarkers for diseases as well.

scholarly journals Revising Endosomal Trafficking under Insulin Receptor Activation

2021 ◽  
Vol 22 (13) ◽  
pp. 6978
Author(s):  
Maria J. Iraburu ◽  
Tommy Garner ◽  
Cristina Montiel-Duarte
Keyword(s):  
Plasma Membrane ◽  
Tyrosine Kinase ◽  
Insulin Receptor ◽  
Molecular Mechanisms ◽  
Receptor Activation ◽  
Small Gtpases ◽  
Early Endosome ◽  
Tyrosine Kinase Receptors ◽  
Endosomal Trafficking ◽  
Cell Functions

The endocytosis of ligand-bound receptors and their eventual recycling to the plasma membrane (PM) are processes that have an influence on signalling activity and therefore on many cell functions, including migration and proliferation. Like other tyrosine kinase receptors (TKR), the insulin receptor (INSR) has been shown to be endocytosed by clathrin-dependent and -independent mechanisms. Once at the early endosome (EE), the sorting of the receptor, either to the late endosome (LE) for degradation or back to the PM through slow or fast recycling pathways, will determine the intensity and duration of insulin effects. Both the endocytic and the endosomic pathways are regulated by many proteins, the Arf and Rab families of small GTPases being some of the most relevant. Here, we argue for a specific role for the slow recycling route, whilst we review the main molecular mechanisms involved in INSR endocytosis, sorting and recycling, as well as their possible role in cell functions.

scholarly journals Atrial Natriuretic Peptide Protects against Histamine-Induced Endothelial Barrier Dysfunction in Vivo

2008 ◽  
Vol 74 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Robert Fürst ◽  
Martin F. Bubik ◽  
Peter Bihari ◽  
Bettina A. Mayer ◽  
Alexander G. Khandoga ◽  
...  
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Endothelial Barrier ◽  
Barrier Dysfunction ◽  
Endothelial Barrier Dysfunction ◽  
Atrial Natriuretic

scholarly journals The MADD-3 LAMMER Kinase Interacts with a p38 MAP Kinase Pathway to Regulate the Display of the EVA-1 Guidance Receptor in Caenorhabditis elegans

PLoS Genetics ◽  
2016 ◽  
Vol 12 (4) ◽  
pp. e1006010 ◽  
Author(s):  
Serena A. D’Souza ◽  
Luckshi Rajendran ◽  
Rachel Bagg ◽  
Louis Barbier ◽  
Derek M. van Pel ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Caenorhabditis Elegans ◽  
Map Kinase ◽  
Motor Neurons ◽  
Leading Edge ◽  
P38 Map Kinase ◽  
Endosomal Trafficking ◽  
Guidance Cue ◽  
Map Kinase Pathway ◽  
Kinase Pathway

The proper display of transmembrane receptors on the leading edge of migrating cells and cell extensions is essential for their response to guidance cues. We previously discovered that MADD-4, which is an ADAMTSL secreted by motor neurons in Caenorhabditis elegans, interacts with an UNC-40/EVA-1 co-receptor complex on muscles to attract plasma membrane extensions called muscle arms. In nematodes, the muscle arm termini harbor the post-synaptic elements of the neuromuscular junction. Through a forward genetic screen for mutants with disrupted muscle arm extension, we discovered that a LAMMER kinase, which we call MADD-3, is required for the proper display of the EVA-1 receptor on the muscle’s plasma membrane. Without MADD-3, EVA-1 levels decrease concomitantly with a reduction of the late-endosomal marker RAB-7. Through a genetic suppressor screen, we found that the levels of EVA-1 and RAB-7 can be restored in madd-3 mutants by eliminating the function of a p38 MAP kinase pathway. We also found that EVA-1 and RAB-7 will accumulate in madd-3 mutants upon disrupting CUP-5, which is a mucolipin ortholog required for proper lysosome function. Together, our data suggests that the MADD-3 LAMMER kinase antagonizes the p38-mediated endosomal trafficking of EVA-1 to the lysosome. In this way, MADD-3 ensures that sufficient levels of EVA-1 are present to guide muscle arm extension towards the source of the MADD-4 guidance cue.

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