Subcellular Localization of the Small GTPase Rab5a in Resting and Stimulated Human Neutrophils

1996 ◽  
Vol 227 (2) ◽  
pp. 367-373 ◽  
Author(s):  
Francesca Vita ◽  
Maria Rosa Soranzo ◽  
Violetta Borelli ◽  
Paolo Bertoncin ◽  
Giuliano Zabucchi
Keyword(s):  
Subcellular Localization ◽  
Small Gtpase ◽  
Human Neutrophils

Subcellular Localization of the Small GTPase Rab5a in Resting and Stimulated Human Neurotrophils

1997 ◽  
Vol 230 (2) ◽  
pp. 415
Author(s):  
Francesca Vita ◽  
Maria Rosa Soranzo ◽  
Violetta Borelli ◽  
Paolo Bertoncin ◽  
Giuliano Zabucchi
Keyword(s):  
Subcellular Localization ◽  
Small Gtpase

scholarly journals Influence of Subcellular Localization and Functional State on Protein Turnover

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1747
Author(s):  
Roya Yousefi ◽  
Kristina Jevdokimenko ◽  
Verena Kluever ◽  
David Pacheu-Grau ◽  
Eugenio F. Fornasiero
Keyword(s):  
Subcellular Localization ◽  
Functional State ◽  
Protein Turnover ◽  
Protein Localization ◽  
Small Gtpase ◽  
Turnover Rates ◽  
Cellular Behavior ◽  
Two Factors ◽  
Brain Creatine Kinase ◽  
Selection Of

Protein homeostasis is an equilibrium of paramount importance that maintains cellular performance by preserving an efficient proteome. This equilibrium avoids the accumulation of potentially toxic proteins, which could lead to cellular stress and death. While the regulators of proteostasis are the machineries controlling protein production, folding and degradation, several other factors can influence this process. Here, we have considered two factors influencing protein turnover: the subcellular localization of a protein and its functional state. For this purpose, we used an imaging approach based on the pulse-labeling of 17 representative SNAP-tag constructs for measuring protein lifetimes. With this approach, we obtained precise measurements of protein turnover rates in several subcellular compartments. We also tested a selection of mutants modulating the function of three extensively studied proteins, the Ca2+ sensor calmodulin, the small GTPase Rab5a and the brain creatine kinase (CKB). Finally, we followed up on the increased lifetime observed for the constitutively active Rab5a (Q79L), and we found that its stabilization correlates with enlarged endosomes and increased interaction with membranes. Overall, our data reveal that both changes in protein localization and functional state are key modulators of protein turnover, and protein lifetime fluctuations can be considered to infer changes in cellular behavior.

scholarly journals Phosphorylation by Protein Kinase Cα Regulates RalB Small GTPase Protein Activation, Subcellular Localization, and Effector Utilization

2012 ◽  
Vol 287 (18) ◽  
pp. 14827-14836 ◽  
Author(s):  
Timothy D. Martin ◽  
Natalia Mitin ◽  
Adrienne D. Cox ◽  
Jen Jen Yeh ◽  
Channing J. Der
Keyword(s):  
Protein Kinase ◽  
Subcellular Localization ◽  
Small Gtpase ◽  
Protein Activation ◽  
Protein Kinase Cα

scholarly journals Subcellular localization and translocation of the receptor for N-formylmethionyl-leucyl-phenylalanine in human neutrophils

1994 ◽  
Vol 299 (2) ◽  
pp. 473-479 ◽  
Author(s):  
H Sengeløv ◽  
F Boulay ◽  
L Kjeldsen ◽  
N Borregaard
Keyword(s):  
Plasma Membrane ◽  
Subcellular Localization ◽  
Plasma Membranes ◽  
Secretory Vesicle ◽  
Human Neutrophils ◽  
Secretory Vesicles ◽  
Beta Band ◽  
Neutrophil Gelatinase Associated Lipocalin ◽  
Specific Granules ◽  
Inflammatory Stimuli

The subcellular localization of N-formylmethionyl-leucyl-phenylalanine (fMLP) receptors in human neutrophils was investigated. The fMLP receptor was detected with a high-affinity, photoactivatable, radioiodinated derivative of N-formyl-methionyl-leucyl-phenylalanyl-lysine (fMLFK). Neutrophils were disrupted by nitrogen cavitation and fractionated on Percoll density gradients. fMLP receptors were located in the beta-band containing gelatinase and specific granules, and in the gamma-band containing plasma membrane and secretory vesicles. Plasma membranes and secretory vesicles were separated by high-voltage free-flow electrophoresis, and secretory vesicles were demonstrated to be highly enriched in fMLP receptors. The receptors found in secretory vesicles translocated fully to the plasma membrane upon stimulation with inflammatory mediators. The receptor translocation from the beta-band indicated that the receptor present there was mainly located in gelatinase granules. A 25 kDa fMLP-binding protein was found in the beta-band. Immunoprecipitation revealed that this protein was identical with NGAL (neutrophil gelatinase-associated lipocalin), a novel protein found in specific granules. In summary, we demonstrate that the compartment in human neutrophils that is mobilized most easily and fastest, the secretory vesicle, is a major reservoir of fMLP receptors. This explains the prompt and extensive upregulation of fMLP receptors on the neutrophil surface in response to inflammatory stimuli.

scholarly journals The Thyroid Hormone Inactivating Enzyme Type 3 Deiodinase is Present in Bactericidal Granules and the Cytoplasm of Human Neutrophils

Endocrinology ◽  
2016 ◽  
Vol 157 (8) ◽  
pp. 3293-3305 ◽  
Author(s):  
Anne H. van der Spek ◽  
Flavia F. Bloise ◽  
Wikky Tigchelaar ◽  
Monica Dentice ◽  
Domenico Salvatore ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Subcellular Localization ◽  
Subcellular Location ◽  
Essential Elements ◽  
Neutrophil Extracellular Trap ◽  
Human Neutrophils ◽  
Transcriptional Level ◽  
Bacterial Killing ◽  
Effector Cells ◽  
Type 3

Neutrophils are important effector cells of the innate immune system. Thyroid hormone (TH) is thought to play an important role in their function. Intracellular TH levels are regulated by the deiodinating enzymes. The TH-inactivating type 3 deiodinase (D3) is expressed in infiltrating murine neutrophils, and D3 knockout mice show impaired bacterial killing upon infection. This suggests that D3 plays an important role in the bacterial killing capacity of neutrophils. The mechanism behind this effect is unknown. We aimed to assess the presence of D3 in human neutrophils, and determine its subcellular localization using confocal and electron microscopy, because this could give important clues about its function in these cells. D3 appeared to be present in the cytoplasm and in myeloperoxidase containing azurophilic granules and as well as lactoferrin containing specific granules within human neutrophils. This subcellular localization did not change upon activation of the cells. D3 is observed intracellularly during neutrophil extracellular trap formation, followed by a reduction of D3 staining after release of the neutrophil extracellular traps into the extracellular space. At the transcriptional level, human neutrophils expressed additional essential elements of TH metabolism, including TH transporters and TH receptors. Here, we demonstrate the presence and subcellular location of D3 in human neutrophils for the first time and propose a model, in which D3 plays a role in the bacterial killing capacity of neutrophils either through generation of iodide for the myeloperoxidase system or through modulation of intracellular TH bioavailability.

scholarly journals Subcellular localization of NAD(P)H oxidase(s) in human neutrophilic polymorphonuclear leucocytes

1978 ◽  
Vol 176 (1) ◽  
pp. 175-178 ◽  
Author(s):  
D B Iverson ◽  
P Wang-Iverson ◽  
J K Spitznagel ◽  
L R DeChatelet
Keyword(s):  
Cell Membrane ◽  
Nadph Oxidase ◽  
Subcellular Localization ◽  
Density Gradient ◽  
Membrane Fraction ◽  
Sucrose Density Gradient ◽  
Human Neutrophils ◽  
Polymorphonuclear Leucocytes

NADH and NADPH oxidase activities in a homogenate of human neutrophils co-sediment in a linear sucrose density gradient under either velocity or isopycnic conditions of centrifugation. The position of these activities in the gradient does not correspond to any known subcellular granule or to the cell-membrane fraction. These data suggest that the oxidase activities may reside in a unique granule that has previously not been recognized.

scholarly journals Subcellular localization of the superoxide-forming enzyme in human neutrophils.

1979 ◽  
Vol 63 (1) ◽  
pp. 21-29 ◽  
Author(s):  
B Dewald ◽  
M Baggiolini ◽  
J T Curnutte ◽  
B M Babior
Keyword(s):  
Subcellular Localization ◽  
Human Neutrophils

scholarly journals Activation of the Small GTPase Rap1 in Human Neutrophils

Blood ◽  
1998 ◽  
Vol 92 (6) ◽  
pp. 2133-2140 ◽  
Author(s):  
Laura M’Rabet ◽  
Paul Coffer ◽  
Fried Zwartkruis ◽  
Barbara Franke ◽  
Anthony W. Segal ◽  
...  
Keyword(s):  
Platelet Activating Factor ◽  
Small Gtpase ◽  
Human Neutrophils ◽  
Coated Particles ◽  
Gm Csf ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
American Society ◽  
Rap1 Activation ◽  
Stimulating Factor

Abstract The small GTPase Rap1 is highly expressed in human neutrophils, but its function is largely unknown. Using the Rap1-binding domain of RalGDS (RalGDS-RBD) as an activation-specific probe for Rap1, we have investigated the regulation of Rap1 activity in primary human neutrophils. We found that a variety of stimuli involved in neutrophil activation, including fMet-Leu-Phe (fMLP), platelet-activating factor (PAF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and IgG-coated particles, induce a rapid and transient Rap1 activation. In addition, we found that Rap1 is normally activated in neutrophils from chronic granulomatous disease patients that lack cytochrome b558 or p47phox and have a defective NADPH oxidase system. From these results we conclude that in neutrophils Rap1 is activated independently of respiratory burst induction. Finally, we found that Rap1 is activated by both the Ca2+ ionophore ionomycin and the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA), indicating that phospholipase C (PLC) activation leading to elevated levels of intracellular free Ca2+ and diacylglycerol (DAG) can mediate Rap1 activation. However, inhibition of PLC and Ca2+ depletion only marginally affected fMLP-induced Rap1 activation, suggesting that additional pathways may control Rap1 activation. © 1998 by The American Society of Hematology.

Expression and subcellular localization of syntaxin 11 in human neutrophils

2009 ◽  
Vol 58 (7) ◽  
pp. 407-412 ◽  
Author(s):  
Li-xin Xie ◽  
Janis de la Iglesia-Vicente ◽  
Yun-xiang Fang ◽  
Faustino Mollinedo
Keyword(s):  
Subcellular Localization ◽  
Human Neutrophils ◽  
Syntaxin 11
Sign in / Sign up

Export Citation Format

Share Document