Characterization of Endophilin B1b, a brain-specific membrane-associated lysophosphatidic acid acyl transferase with properties distinct from endophilin A1.
AuthorsModregger J, Schmidt AA, Ritter B, Huttner WB, Plomann M
JournalJ Biol Chem
PubMed ID12456676
We have characterized mammalian endophilin B1, a novel member of the endophilins and a representative of their B subgroup. The endophilins B show the same domain organization as the endophilins A, which contain an N-terminal domain responsible for lipid binding and lysophosphatidic acid acyl transferase activity, a central coiled-coil domain ... More
Interactions between Piccolo and the actin/dynamin-binding protein Abp1 link vesicle endocytosis to presynaptic active zones.
AuthorsFenster SD, Kessels MM, Qualmann B, Chung WJ, Nash J, Gundelfinger ED, Garner CC
JournalJ Biol Chem
PubMed ID12654920
'Piccolo is a high molecular weight multi-domain protein shown to be a structural component of the presynaptic CAZ (cytoskeletal matrix assembled at active zones). These features indicate that Piccolo may act to scaffold proteins involved in synaptic vesicle endo- and exocytosis near their site of action. To test this hypothesis, ... More
Receptor-mediated endocytosis of transferrin and the uptake of fe in K562 cells: identification of a nonlysosomal acidic compartment.
'At physiological temperature, the Fe-carrier transferrin is taken up by K562 human erythroleukemia cells through receptor-mediated endocytosis. Both ligand (now minus Fe) and receptor recycle back to the cell surface where the receptor is rapidly reutilized. After endocytosis, transferrin becomes transiently lodged within an acidic compartment inside the cell, as ... More
Defective acidification of intracellular organelles in cystic fibrosis.
AuthorsBarasch J, Kiss B, Prince A, Saiman L, Gruenert D, al-Awqati Q
JournalNature
PubMed ID1712081
'The phenotype of cystic fibrosis (CF) includes abnormalities in transepithelial transport of Cl- (refs 1-5), decreased sialylation and increased sulphation and fucosylation of glycoproteins, and lung colonization with Pseudomonas. It is not apparent how these abnormalities are interrelated, nor how they result from loss of function of the CF gene-encoded ... More
Imaging of receptor trafficking by using alpha-bungarotoxin-binding-site-tagged receptors.
AuthorsSekine-Aizawa Y, Huganir RL,
JournalProc Natl Acad Sci U S A
PubMed ID15563595
'alpha-Amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) receptors mediate excitatory synaptic transmission and are dynamically regulated during synaptic plasticity in the CNS. The membrane trafficking of AMPA receptors to synapses is critical for the regulation of the efficacy of excitatory synaptic transmission. Direct imaging of AMPA receptors in various cell compartments is important to dissecting ... More
Absence of Na+,K(+)-ATPase regulation of endosomal acidification in K562 erythroleukemia cells. Analysis via inhibition of transferrin recycling by low temperatures.
AuthorsSipe DM, Jesurum A, Murphy RF
JournalJ Biol Chem
PubMed ID1847374
'Transferrin (Tf) acidification has been shown to be limited to pH 6 in murine Balb/c 3T3 fibroblasts, human A549 epidermoid carcinoma cells, and Chinese hamster ovary cells and is followed by alkalinization during recycling. In contrast, Tf acidification in the human erythroleukemic cell line K562 proceeds to below pH 5.5, ... More
Acidification of endosome subpopulations in wild-type Chinese hamster ovary cells and temperature-sensitive acidification-defective mutants.
AuthorsSchmid S, Fuchs R, Kielian M, Helenius A, Mellman I
JournalJ Cell Biol
PubMed ID2925786
'During endocytosis in Chinese hamster ovary (CHO) cells, Semliki Forest virus (SFV) passes through two distinct subpopulations of endosomes before reaching lysosomes. One subpopulation, defined by cell fractionation using free flow electrophoresis as "early endosomes," constitutes the major site of membrane and receptor recycling; while "late endosomes," an electrophoretically distinct ... More
High density of octaarginine stimulates macropinocytosis leading to efficient intracellular trafficking for gene expression.
AuthorsKhalil IA, Kogure K, Futaki S, Harashima H
JournalJ Biol Chem
PubMed ID16326716
'The mechanism of the arginine-rich peptide-mediated cellular uptake is currently a controversial issue. Several factors, including the type of peptide, the nature of the cargo, and the linker between them, appear to affect uptake. One of the less studied factors, which may affect the uptake mechanism, is the effect of ... More
Direct observation of endocytosis of gastrin releasing peptide and its receptor.
Authors Grady E F; Slice L W; Brant W O; Walsh J H; Payan D G; Bunnett N W;
JournalJ Biol Chem
PubMed ID7876231
'Endocytosis of the gastrin releasing peptide receptor (GRP-R) may regulate cellular responses to GRP. We observed endocytosis in transfected epithelial cells by confocal microscopy using cyanine 3-GRP (cyanine 3.18-labeled gastrin releasing peptide) and GRP-R antibodies. At 4 degrees C, cy3-GRP and GRP-R were confined to the plasma membrane. After 5 ... More
The receptor recycling pathway contains two distinct populations of early endosomes with different sorting functions.
AuthorsSheff DR, Daro EA, Hull M, Mellman I
JournalJ Cell Biol
PubMed ID10189373
'Receptor recycling involves two endosome populations, peripheral early endosomes and perinuclear recycling endosomes. In polarized epithelial cells, either or both populations must be able to sort apical from basolateral proteins, returning each to its appropriate plasma membrane domain. However, neither the roles of early versus recycling endosomes in polarity nor ... More
Functional expression of the human transferrin receptor cDNA in Chinese hamster ovary cells deficient in endogenous transferrin receptor.
AuthorsMcGraw TE, Greenfield L, Maxfield FR
JournalJ Cell Biol
PubMed ID3611186
'Transferrin (Tf) receptor-variant Chinese hamster ovary cells have been isolated by selection for resistance to two Tf-toxin conjugates. The hybrid toxins contain Tf covalently linked to ricin A chain or a genetically engineered diphtheria toxin fragment. The Tf-receptor-variant (TRV) cells do not have detectable cell-surface Tf receptor; they do not ... More
Inhibition of endosome function in CHO cells bearing a temperature-sensitive defect in the coatomer (COPI) component epsilon-COP.
AuthorsDaro E, Sheff D, Gomez M, Kreis T, Mellman I
JournalJ Cell Biol
PubMed ID9412469
'Recent evidence has suggested that subunits of the coatomer protein (COPI) complexes are functionally associated with endosomes in mammalian cells. We now provide genetic evidence that COPI plays a role in endocytosis in intact cells. The ldlF mutant CHO cell line bears a temperature-sensitive defect in the COPI subunit epsilon-COP. ... More
Luminescence quenching by long range electron transfer: a probe of protein clustering and conformation at the cell surface.
AuthorsMatko J, Jenei A, Wei T, Edidin M
JournalCytometry
PubMed ID7736865
'Quenching of luminescence from fluorescent and phosphorescent probes by nitroxide spin labels with a long range electron transfer (LRET) mechanism (44,45) has been tested as a tool to monitor association/clustering and conformational changes of cell surface proteins. The membrane proteins were labeled with monoclonal antibodies or Fab fragments conjugated with ... More
Calcium chelators induce association with the detergent-insoluble cytoskeleton and functional inactivation of the transferrin receptor in reticulocytes.
AuthorsMorgan EH
JournalBiochim Biophys Acta
PubMed ID2541787
'Incubation of reticulocytes with EDTA, EGTA (ethylene glycol bis(beta-aminoethyl ether)-N,N,N'',N''-tetraacetic acid) and BAPTA (1,2-bis(2-aminophenoxy)ethane-N,N,N'',N''-tetraacetic acid), but not with desferrioxamine B, at temperatures above 20 degrees C resulted in the loss of their ability to take up iron in a temperature-, time- and concentration-dependent manner. No inhibition of transferrin or iron ... More
Diltiazem inhibits transferrin receptor expression and causes G1 arrest in normal and neoplastic T cells.
'Transferrin receptor expression is essential for the proliferation of both normal and malignant T cells. While transferrin receptor expression in normal T cells is tightly coupled to interleukin-2 receptor expression, transferrin receptor expression in malignant cells is usually constitutive and is released from this constraint. Temporally, the appearance of these ... More
Kinetic characterization of reductant dependent processes of iron mobilization from endocytic vesicles.
AuthorsWatkins JA, Altazan JD, Elder P, Li CY, Nunez MT, Cui XX, Glass J
JournalBiochemistry
PubMed ID1535218
'The reductant dependence of iron mobilization from isolated rabbit reticulocyte endosomes containing diferric transferrin is reported. The kinetic effects of acidification by a H(+)-ATPase are eliminated by incubating the endosomes at pH 6.0 in the presence of 15 microM FCCP to acidify the intravesicular milieu and to dissociate 59Fe(III) from ... More
Interaction of cationic colloids at the surface of J774 cells: a kinetic analysis.
AuthorsChenevier P, Veyret B, Roux D, Henry-Toulmé N
JournalBiophys J
PubMed ID10968993
'We have characterized the binding of multilamellar colloids to J774 cells. Cationic colloids were shown to bind much more efficiently than neutral ones. Particle uptake by cells was followed by flow cytometry and fluorescence microscopy. Analysis of the kinetics of uptake of cationic particles indicated that binding on the cell ... More
The recycling endosome of Madin-Darby canine kidney cells is a mildly acidic compartment rich in raft components.
AuthorsGagescu R, Demaurex N, Parton RG, Hunziker W, Huber LA, Gruenberg J
JournalMol Biol Cell
PubMed ID10930469
'We present a biochemical and morphological characterization of recycling endosomes containing the transferrin receptor in the epithelial Madin-Darby canine kidney cell line. We find that recycling endosomes are enriched in molecules known to regulate transferrin recycling but lack proteins involved in early endosome membrane dynamics, indicating that recycling endosomes are ... More
The endocytosis of epidermal growth factor in A431 cells: a pH of microenvironment and the dynamics of receptor complex dissociation.
AuthorsSorkin AD, Teslenko LV, Nikolsky NN
JournalExp Cell Res
PubMed ID2894318
'The endocytosis and intracellular fate of epidermal growth factor (EGF) were studied in A431 cells. After 15-20 min of internalization at 37 degrees C, rhodamine-labeled EGF (EGF-Rh) accumulated into large juxtanuclear compartment consisting of closely related vesicles. This structure was shown to be localized in the para-Golgi region. Fluorescein-labeled transferrin ... More
Characterization of the Calu-3 cell line as a tool to screen pulmonary drug delivery.
AuthorsFoster KA, Avery ML, Yazdanian M, Audus KL
JournalInt J Pharm
PubMed ID11064206
'The objective of this research was to examine the human sub-bronchial gland cell line, Calu-3, and assess its potential as a metabolic and transport model to study drug delivery to the respiratory epithelium. The present studies were conducted using Calu-3 cells grown in Transwells(R) or in multiwell cluster plates. TEER ... More
Selective translocation of the A chain of diphtheria toxin across the membrane of purified endosomes.
AuthorsBeaumelle B, Bensammar L, Bienvenüe A
JournalJ Biol Chem
PubMed ID1597480
'Translocation is a necessary and rate-limiting step for diphtheria toxin (DT) cytotoxicity. We have reconstituted DT translocation in a cell-free system using endosomes purified from lymphocytes and have demonstrated this using two different probe/cell systems, which provided identical results: 125I-DT/human CEM cells and 125I-transferrin-DT/mouse BW cells. The cell-free DT translocation ... More
Trafficking of Shigella lipopolysaccharide in polarized intestinal epithelial cells.
'Bacterial lipopolysaccharide (LPS) at the apical surface of polarized intestinal epithelial cells was previously shown to be transported from the apical to the basolateral pole of the epithelium (Beatty, W.L., and P.J. Sansonetti. 1997. Infect. Immun. 65:4395-4404). The present study was designed to elucidate the transcytotic pathway of LPS and ... More
Role of the basic, proline-rich region of dynamin in Src homology 3 domain binding and endocytosis.
AuthorsOkamoto PM, Herskovits JS, Vallee RB
JournalJ Biol Chem
PubMed ID9111080
'The GTPase dynamin has been implicated in the regulation of the scission of coated and noncoated pits during the early stages of endocytosis. Various macromolecules including microtubules, acidic phospholipids, and Src homology 3 (SH3) domains have been shown to interact with the basic, proline-rich region of dynamin and act as ... More
Tyrosine and serine protein kinase activities associated with ligand-induced internalized TCR/CD3 complexes.
AuthorsLuton F, Legendre V, Gorvel JP, Schmitt-Verhulst AM, Boyer C
JournalJ Immunol
PubMed ID9120267
'Ligand engagement of the TCR/CD3 complex leads to its internalization and modulation from the cell surface. In the present study, we analyzed the intracellular fate of internalized TCR/CD3 complexes following activation of a CTL clone with an anti-clonotypic mAb (anti-TCR mAb). Confocal microscopy using fluorescent anti-TCR mAb showed that after ... More
Uptake of iron from transferrin by isolated rat hepatocytes. A redox-mediated plasma membrane process?
AuthorsThorstensen K, Romslo I
JournalJ Biol Chem
PubMed ID3379048
'The uptake of iron from transferrin by isolated rat hepatocytes varies in parallel with plasma membrane NADH:ferricyanide oxidoreductase activity, is inhibited by ferricyanide, ferric, and ferrous iron chelators, divalent transition metal cations, and depends on calcium ions. Iron uptake does not depend on endosomal acidification or endocytosis of transferrin. The ... More
Transferrin receptor containing the SDYQRL motif of TGN38 causes a reorganization of the recycling compartment but is not targeted to the TGN.
AuthorsJohnson AO, Ghosh RN, Dunn KW, Garippa R, Park J, Mayor S, Maxfield FR, McGraw TE
JournalJ Cell Biol
PubMed ID8991088
'The SDYQRL motif of the cytoplasmic domain of TGN38 is involved in targeting TGN38 from endosomes to the TGN. To create a system for studying this pathway, we replaced the native transferrin receptor (TR) internalization motif (YTRF) with the SDYQRL TGN-targeting motif. The advantages of using TR as a reporter ... More
Intersection of group I CD1 molecules and mycobacteria in different intracellular compartments of dendritic cells.
AuthorsSchaible UE, Hagens K, Fischer K, Collins HL, Kaufmann SH
JournalJ Immunol
PubMed ID10779793
'Human CD1a, CD1b, and CD1c molecules can present mycobacterial glycolipids to T cells. Because phagosomes containing viable mycobacteria represent early endosomal compartments, we studied where mycobacterial glycolipids intersect with CD1 molecules in infected APC. CD1b and CD1c, but not CD1a, localized to late endosomes/lysosomes. CD1a and CD1c were predominantly expressed ... More
The role of transferrin-receptor variation in the host range of Trypanosoma brucei.
AuthorsBitter W, Gerrits H, Kieft R, Borst P
JournalNature
PubMed ID9461219
'Trypanosoma brucei is a unicellular parasite transmitted between African mammals by tsetse flies. T. brucei multiplies freely in the bloodstream of many different mammals, and survives by antigenic variation of the main component of its surface coat, variant surface glycoprotein (VSG). Trypanosomes take up transferrin through a heterodimeric transferrin receptor, ... More
Receptor-mediated endocytosis of alpha 2-macroglobulin and transferrin in rat caput epididymal epithelial cells in vitro.
AuthorsDjakiew D, Byers SW, Dym M
JournalBiol Reprod
PubMed ID6083810
'The endocytic activity of epithelial cells from the rat epididymis in vitro has been examined by following the uptake of tracer compounds conjugated to proteins. Transferrin-gold and alpha 2-macroglobulin-gold were taken up initially in coated pits, internalized and sequestered into tubular-vesicular structures, multivesicular bodies and, in the case of alpha ... More
ATP-dependent translocation of ricin across the membrane of purified endosomes.
AuthorsBeaumelle B, Alami M, Hopkins CR
JournalJ Biol Chem
PubMed ID7901210
'Ricin translocation was demonstrated (using both fluorescence- and radiolabel-based assays) across the membrane of endosomes purified from mouse lymphocytes. Selectivity of the process was shown by the absence of translocation activity of transferrin and horseradish peroxidase used as membrane-bound and fluid-phase endosome labels, respectively. Endocytosed 125I-ricin translocation was found to ... More
'Dynamin is a 100-kD microtubule-activated GTPase. Recent evidence has revealed a high degree of sequence homology with the product of the Drosophila gene shibire, mutations in which block the recycling of synaptic vesicles and, more generally, the formation of coated and non-coated vesicles at the plasma membrane. We have now ... More
Receptor-mediated endocytosis: the intracellular journey of transferrin and its receptor.
AuthorsDautry-Varsat A
JournalBiochimie
PubMed ID2874839
'A variety of ligands and macromolecules enter cells by receptor-mediated endocytosis. Ligands bind to their receptors on the cell surface and ligand-receptor complexes are localized in specialized regions of the plasma membrane called coated pits. Coated pits invaginate and give rise to intracellular coated vesicles containing ligand-receptor complexes which are ... More
Fluorometric determination of bacterial protease activity using fluorescein isothiocyanate-labeled proteins as substrates.
AuthorsHomer KA, Beighton D
JournalAnal Biochem
PubMed ID2127659
'Intact fluorescein isothiocyanate-labeled proteins have relatively low background fluorescence at excitation and emission wavelengths of 495 and 525 nm, respectively. Degradation of these substrates leads to exposure of covalently linked fluorescein isothiocyanate molecules and to a concomitant increase in relative fluorescence at these wavelengths. The increase in relative fluorescence is ... More
Optical aberrations and objective choice in multicolor confocal microscopy.
AuthorsDunn KW, Wang E
JournalBiotechniques
PubMed ID10723569
'Refinements in design have simplified confocal microscopy to the extent that it has become a standard research tool in cell biology. However, as confocal microscopes have become more powerful, they have also become more demanding of their optical components. In fact, optical aberrations that cause subtle defects in image quality ... More
Endosome dynamics regulated by a Rho protein.
AuthorsMurphy C, Saffrich R, Grummt M, Gournier H, Rybin V, Rubino M, Auvinen P, Lütcke A, Parton RG, Zerial M
JournalNature
PubMed ID8945468
Vesicular transport is a dynamic process that requires coordinated interactions between membrane and cytoskeleton. The mechanisms and molecules integrating these interactions are unclear. A Rho protein, RhoD, might provide a molecular link between membrane traffic and the cytoskeleton. Activated RhoD causes rearrangements of the actin cytoskeleton and cell surface, and ... More
In migrating fibroblasts, recycling receptors are concentrated in narrow tubules in the pericentriolar area, and then routed to the plasma membrane of the leading lamella.
AuthorsHopkins CR, Gibson A, Shipman M, Strickland DK, Trowbridge IS
JournalJ Cell Biol
PubMed ID7515888
By following the intracellular processing of recycling transferrin receptors and the selective sorting of a-2 macroglobulin in chick embryo fibroblasts, we have shown that the concentration of 60 nm diam tubules which surrounds the centrioles represents a distal compartment on the recycling pathway. In migrating cells transferrin receptor tracers can ... More
Perturbation of intracellular pH by DIDS on endocytosis of transferrin and iron uptake in rabbit reticulocytes.
AuthorsChan RY, Loh TT
JournalBiochem Biophys Res Commun
PubMed ID3342069
DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonic acid) inhibited transferrin and iron uptake by rabbit reticulocytes in a dose-dependent manner. Measurement of intracellular pH shows that DIDS neutralized the pH in the intracellular vesicles and at the same time, rendered the cytoplasmic pH more acidic. The latter may be the result of a perturbance in ... More
Fluorescence probe measurement of the pH of the transferrin microenvironment during iron uptake by rat bone marrow erythroid cells.
AuthorsVeldman A, Van der Heul C, Kroos MJ, Van Eijk HG
JournalBr J Haematol
PubMed ID3942693
Fluorescence probe measurements of the transferrin micro-environment during iron uptake by rat erythroid cells revealed that part of the transferrin is taken up in an acidic environment. The pH of this intracellular transferrin environment is 5.7. When rat erythroid cell precursors are incubated with diferric transferrin then in the incubation ... More
Oxalate and spin-labeled oxalate as probes of the anion binding site of human transferrin. Metal to anion distance.
AuthorsNajarian RC, Harris DC
JournalJ Biol Chem
PubMed ID22546
The spin-labeled anion N-[4-(2,2,6,6-tetramethylpiperidin-1-oxyl)] oxamate has been synthesized and characterized. In the presence of this compound, a specific iron-transferrin-anion complex is formed, as evidenced by the development of a characteristic red color. No EPR signal was observed for the nitroxyl radical in the protein complex, presumably due to broadening of ... More
A review of fluorescence methods for assessing labile iron in cells and biological fluids.
AuthorsEspósito BP, Epsztejn S, Breuer W, Cabantchik ZI
JournalAnal Biochem
PubMed ID11969183
A variety of biochemical, pharmacological, and toxicological properties have been attributed to labile forms of iron that are associated with cells or with biological fluids. Unlike the major fraction of bioiron which is protein bound, the labile bioiron is chelatable and therefore amenable for detection by metal-sensing devices that are ... More
Requirement for the adapter protein GRB2 in EGF receptor endocytosis.
AuthorsWang Z, Moran MF
JournalScience
PubMed ID8658166
Activated epidermal growth factor (EGF) receptors induce the formation of various complexes of intracellular signaling proteins that are mediated by SRC homology 2 (SH2) and SH3 domains. The activated receptors are also rapidly internalized into the endocytotic compartment and degraded in lysosomes. EGF stimulation of canine epithelial cells induced a ... More
Cellular uptake of unconjugated TAT peptide involves clathrin-dependent endocytosis and heparan sulfate receptors.
Delivery of macromolecules mediated by protein transduction domains (PTDs) attracts a lot of interest due to its therapeutic and biotechnological potential. A major reevaluation of the mechanism of PTD-mediated internalization and the role of endocytosis in this mechanism has been recently initiated. Here, we demonstrate that the entry of TAT ... More
Quantification of alpha-fetoprotein and transferrin endocytosis by lymphoid cells using flow cytometry.
Alpha-fetoprotein (AFP) and transferrin (Tf) are serum proteins actively internalized by many growing cells through specific cell surface receptors. The intracellular pathways of AFP and Tf are very similar: both proteins enter the cells via coated pits and receptosomes, move to tubular elements of the transreticular portion of the Golgi ... More
SCAMP1 function in endocytosis.
AuthorsFernández-Chacón R, Achiriloaie M, Janz R, Albanesi JP, Südhof TC
JournalJ Biol Chem
PubMed ID10777571
Secretory carrier membrane proteins (SCAMPs) are ubiquitous components of recycling vesicles that shuttle between the plasma membrane, endosomes, and the trans-Golgi complex. SCAMPs contain multiple N-terminal NPF repeats and four highly conserved transmembrane regions. NPF repeats often interact with EH domain proteins that function in budding of transport vesicles from ... More
In polarized MDCK cells basolateral vesicles arise from clathrin-gamma-adaptin-coated domains on endosomal tubules.
AuthorsFutter CE, Gibson A, Allchin EH, Maxwell S, Ruddock LJ, Odorizzi G, Domingo D, Trowbridge IS, Hopkins CR
JournalJ Cell Biol
PubMed ID9566963
Human transferrin receptors (TR) and receptors for polymeric immunoglobulins (pIgR) expressed in polarized MDCK cells maintain steady-state, asymmetric distributions on the separate basolateral and apical surfaces even though they are trafficking continuously into and across these cells. The intracellular mechanisms required to maintain these asymmetric distributions have not been located. ... More
Tamoxifen inhibits acidification in cells independent of the estrogen receptor.
AuthorsAltan N, Chen Y, Schindler M, Simon SM
JournalProc Natl Acad Sci U S A
PubMed ID10200279
Tamoxifen has been reported to have numerous physiological effects that are independent of the estrogen receptor, including sensitization of resistant tumor cells to many chemotherapeutic agents. Drug-resistant cells sequester weak base chemotherapeutics in acidic organelles away from their sites of action in the cytosol and nucleus. This work reports that ... More
Segregation of transferrin to a mildly acidic (pH 6.5) para-Golgi compartment in the recycling pathway.
To study the intracellular sorting of internalized ligands and receptors, we examined the pathways of two ligands: transferrin, which is recycled, and alpha 2-macroglobulin (alpha 2M), which is degraded. In CHO cells the two ligands rapidly segregate into different intracellular compartments. Within 5 min fluorescein-labeled transferrin (F-Tf) is found in ... More
Intracellular activation of protein kinase C and regulation of the surface transferrin receptor by diacylglycerol is a spontaneously reversible process that is associated with rapid formation of phosphatidic acid.
AuthorsMay WS, Lapetina EG, Cuatrecasas P
JournalProc Natl Acad Sci U S A
PubMed ID3006042
The effect of the synthetic diacylglycerol, sn-1,2-dioctanoylglycerol (diC8), on the expression of the surface transferrin receptor reveals that exogenous diC8 can act as an intracellular activator of protein kinase C and stimulate both down-regulation and increased receptor phosphorylation in a manner similar to that induced by the active tumor promotor, ... More
Role of dynactin in endocytic traffic: effects of dynamitin overexpression and colocalization with CLIP-170.
AuthorsValetti C, Wetzel DM, Schrader M, Hasbani MJ, Gill SR, Kreis TE, Schroer TA
JournalMol Biol Cell
PubMed ID10588646
The flow of material from peripheral, early endosomes to late endosomes requires microtubules and is thought to be facilitated by the minus end-directed motor cytoplasmic dynein and its activator dynactin. The microtubule-binding protein CLIP-170 may also play a role by providing an early link to endosomes. Here, we show that ... More
Cl-, Na+, and H+ fluxes during the acidification of rabbit reticulocyte endocytic vesicles.
AuthorsGaete V, Núñez MT, Glass J
JournalJ Bioenerg Biomembr
PubMed ID1849134
The ionic fluxes associated with the ATP-dependent acidification of endocytic vesicles were studied in a preparation isolated from rabbit reticulocytes enriched for transferrin-transferrin receptor complexes. No vesicle acidification was observed in the absence of intra- and extravesicular ions (sucrose(in)/sucrose(out), while maximal acidification was observed with NaCl(in)/KCl(out).K+(in) was a poor substitute ... More
The kinetics of mannose 6-phosphate receptor trafficking in the endocytic pathway in HEp-2 cells: the receptor enters and rapidly leaves multivesicular endosomes without accumulating in a prelysosomal compartment.
AuthorsHirst J, Futter CE, Hopkins CR
JournalMol Biol Cell
PubMed ID9529379
We have previously shown that in HEp-2 cells, multivesicular bodies (MVBs) processing internalized epidermal growth factor-epidermal growth factor receptor complexes mature and fuse directly with lysosomes in which the complexes are degraded. The MVBs do not fuse with a prelysosomal compartment enriched in mannose 6-phosphate receptor (M6PR) as has been ... More
Coated endosomal vesicles: sorting and recycling compartment for transferrin in BHK cells.
AuthorsEskelinen S, Kok JW, Sormunen R, Hoekstra D
JournalEur J Cell Biol
PubMed ID1802708
We have investigated receptor-mediated endocytosis of transferrin (Tf) in baby hamster kidney (BHK) cells, using fluorescence and electron microscopy, and by carrying out colocalization experiments with clathrin antibodies and a fluorescently tagged glycolipid. Early during internalization, Tf was found in small vesicles (100-150 nm in diameter) located at the cell ... More
Rab11 regulates recycling through the pericentriolar recycling endosome.
AuthorsUllrich O, Reinsch S, Urbé S, Zerial M, Parton RG
JournalJ Cell Biol
PubMed ID8922376
Small GTPases of the rab family are crucial elements of the machinery that controls membrane traffic. In the present study, we examined the distribution and function of rab11. Rab11 was shown by confocal immunofluorescence microscopy and EM to colocalize with internalized transferrin in the pericentriolar recycling compartment of CHO and ... More
Phosphorylation of four amino acid residues in the carboxyl terminus of the rat somatostatin receptor subtype 3 is crucial for its desensitization and internalization.
AuthorsRoth A, Kreienkamp HJ, Meyerhof W, Richter D
JournalJ Biol Chem
PubMed ID9295322
Agonist-dependent internalization of the rat somatostatin receptor subtype 3 (SSTR3) requires four hydroxyl amino acids (Ser341, Ser346, Ser351, and Thr357) in the receptor C terminus (Roth, A., Kreienkamp, H.-J., Nehring, R., Roostermann, D., Meyerhof, W. and Richter, D. (1997) DNA Cell Biol. 16, 111-119). Here we report on the molecular ... More
Multivesicular endosomes containing internalized EGF-EGF receptor complexes mature and then fuse directly with lysosomes.
AuthorsFutter CE, Pearse A, Hewlett LJ, Hopkins CR
JournalJ Cell Biol
PubMed ID8601581
We have followed the transfer of EGF-EGF receptor (EGFR) complexes from endosomal vacuoles that contain transferrin receptors (TfR) to lysosome vacuoles identified by their content of HRP loaded as a 15-min pulse 4 h previously. We show that the HRP-loaded lysosomes are lysosomal-associated membrane protein-1 (LAMP-1) positive, mannose-6-phosphate receptor (M6PR) ... More
Endothelial Ca2+ waves preferentially originate at specific loci in caveolin-rich cell edges.
AuthorsIsshiki M, Ando J, Korenaga R, Kogo H, Fujimoto T, Fujita T, Kamiya A
JournalProc Natl Acad Sci U S A
PubMed ID9560219
Stimulation of endothelial cells (ECs) with ATP evoked an increase in intracellular Ca2+ concentration ([Ca2+]i). In a single bovine aortic EC, the [Ca2+]i rise started at a specific peripheral locus and propagated throughout the entire cell as a Ca2+ wave. The initiation locus was constant upon repeated stimulation with ATP ... More
Distinct protein sorting and localization to premelanosomes, melanosomes, and lysosomes in pigmented melanocytic cells.
AuthorsRaposo G, Tenza D, Murphy DM, Berson JF, Marks MS
JournalJ Cell Biol
PubMed ID11266471
Melanosomes and premelanosomes are lysosome-related organelles with a unique structure and cohort of resident proteins. We have positioned these organelles relative to endosomes and lysosomes in pigmented melanoma cells and melanocytes. Melanosome resident proteins Pmel17 and TRP1 localized to separate vesicular structures that were distinct from those enriched in lysosomal ... More
Tyrosine-containing motif that transduces cell activation signals also determines internalization and antigen presentation via type III receptors for IgG.
AuthorsAmigorena S, Salamero J, Davoust J, Fridman WH, Bonnerot C
JournalNature
PubMed ID1386408
Type III receptors for IgG (Fc gamma RII; ref. 1), high-affinity IgE receptors (Fc epsilon RI; ref. 2), as well as the T- and B-cell antigen receptors, consist of multiple components with specialized ligand-binding and signal transduction functions. Fc gamma RII alpha (ligand-binding) and gamma (signal-transducing) subunits are expressed in ... More
Defective acidification in human breast tumor cells and implications for chemotherapy.
AuthorsAltan N, Chen Y, Schindler M, Simon SM
JournalJ Exp Med
PubMed ID9584137
Multidrug resistance (MDR) is a significant problem in the treatment of cancer. Chemotherapeutic drugs distribute through the cyto- and nucleoplasm of drug-sensitive cells but are excluded from the nucleus in drug-resistant cells, concentrating in cytoplasmic organelles. Weak base chemotherapeutic drugs (e.g., anthracyclines and vinca alkaloids) should concentrate in acidic organelles. ... More
Endocytosis resumes during late mitosis and is required for cytokinesis.
AuthorsSchweitzer JK, Burke EE, Goodson HV, D'Souza-Schorey C
JournalJ Biol Chem
PubMed ID16207714
Recent work has underscored the importance of membrane trafficking events during cytokinesis. For example, targeted membrane secretion occurs at the cleavage furrow in animal cells, and proteins that regulate endocytosis also influence the process of cytokinesis. Nonetheless, the prevailing dogma is that endosomal membrane trafficking ceases during mitosis and resumes ... More
Signal transduction and hormone-dependent internalization of the thyrotropin-releasing hormone receptor in cells lacking Gq and G11.
AuthorsYu R, Hinkle PM
JournalJ Biol Chem
PubMed ID10336475
The thyrotropin-releasing hormone (TRH) receptor was expressed in embryonic fibroblasts from mice lacking the alpha subunits of Gq and G11 (Fq/11 cells) to determine whether G protein coupling is necessary for agonist-dependent receptor internalization. Neither TRH nor agonists acting on endogenous receptors increased intracellular calcium unless the cells were co-transfected ... More
Rac1-induced endocytosis is associated with intracellular proteolysis during migration through a three-dimensional matrix.
AuthorsAhram M, Sameni M, Qiu RG, Linebaugh B, Kirn D, Sloane BF
JournalExp Cell Res
PubMed ID11035924
Transfection of Rat1 fibroblasts with an activated form of rac1 (V12rac1) stimulated cell migration in vitro compared to transfection of Rat1 fibroblasts with vector only or with dominant negative rac1 (N17rac1). To investigate the involvement of proteases in this migration, we used a novel confocal assay to evaluate the ability ... More
Endocytic pathways in polarized Caco-2 cells: identification of an endosomal compartment accessible from both apical and basolateral surfaces.
AuthorsHughson EJ, Hopkins CR
JournalJ Cell Biol
PubMed ID2298809
The enterocyte-like cell line Caco-2 forms a polarized epithelium when grown on filters. We have investigated the interaction of endocytic pathways from the apical and basolateral surfaces. The transferrin receptor was an appropriate marker for the basolateral route; uptake of radiolabeled transferrin was highly polarized, and recycling of this ligand ... More
A role for calmodulin in organelle membrane tubulation.
Authorsde Figueiredo P, Brown WJ
JournalMol Biol Cell
PubMed ID7579700
Membrane tubules of uniform diameter (60-80 nm) and variable lengths have been seen to extend from the main bodies of the Golgi complex, trans Golgi network (TGN), and endosomes. In the case of endosomes, these tubules appear to mediate membrane and receptor recycling events. Brefeldin A (BFA) is a potent ... More
The actin-binding protein comitin (p24) is a component of the Golgi apparatus.
AuthorsWeiner OH, Murphy J, Griffiths G, Schleicher M, Noegel AA
JournalJ Cell Biol
PubMed ID8408201
Comitin (p24) was first identified in Dictyostelium discoideum as a membrane-associated protein which binds in gel overlay assays to G and F actin. To analyze its actin-binding properties we used purified, bacterially expressed comitin and found that it binds to F actin in spin down experiments and increases the viscosity ... More
Cellubrevin is present in the basolateral endocytic compartment of hepatocytes and follows the transcytotic pathway after IgA internalization.
AuthorsCalvo M, Pol A, Lu A, Ortega D, Pons M, Blasi J, Enrich C
JournalJ Biol Chem
PubMed ID10713107
The endocytic compartment of polarized cells is organized in basolateral and apical endosomes plus those endocytic structures specialized in recycling and transcytosis, which are still poorly characterized. The complexity of the various populations of endosomes has been demonstrated by the exquisite repertoire of endogenous proteins. In this study we examined ... More
Studies of transferrin recycling reconstituted in streptolysin O permeabilized Chinese hamster ovary cells.
AuthorsMartys JL, Shevell T, McGraw TE
JournalJ Biol Chem
PubMed ID7592788
Efficient transferrin receptor recycling is reconstituted when donor cytosol and ATP are added to the streptolysin O permeabilized cells. The rate of reconstituted recycling is dependent on the concentration of donor cytosol. The cytosol provides a factor(s) required for the transport of transferrin from the pericentriolar recycling compartment to the ... More
Bafilomycin A1 treatment retards transferrin receptor recycling more than bulk membrane recycling.
AuthorsPresley JF, Mayor S, McGraw TE, Dunn KW, Maxfield FR
JournalJ Biol Chem
PubMed ID9153255
Treatment of Chinese hamster ovary cells with the vacuolar proton pump inhibitor bafilomycin A1 causes a 2-fold retardation in the rate of recycling of transfected human transferrin receptors back to the cell surface as measured using biochemical assays (Johnson, L. S. , Dunn, K. W., Pytowski, B., and McGraw, T. ... More
Ligand-induced internalization of neurotensin in transfected COS-7 cells: differential intracellular trafficking of ligand and receptor.
AuthorsVandenbulcke F, Nouel D, Vincent JP, Mazella J, Beaudet A
JournalJ Cell Sci
PubMed ID10934036
The neuropeptide neurotensin (NT) is known to be internalized in a receptor-mediated fashion into its target cells. To gain insight into the mechanisms underlying this process, we monitored in parallel the migration of the NT1 neurotensin receptor subtype and a fluorescent analog of NT (fluo-NT) in COS-7 cells transfected with ... More
A clathrin/dynamin- and mannose-6-phosphate receptor-independent pathway for granzyme B-induced cell death.
AuthorsTrapani JA, Sutton VR, Thia KY, Li YQ, Froelich CJ, Jans DA, Sandrin MS, Browne KA
JournalJ Cell Biol
PubMed ID12538642
The 280-kD cation-independent mannose-6-phosphate receptor (MPR) has been shown to play a role in endocytic uptake of granzyme B, since target cells overexpressing MPR have an increased sensitivity to granzyme B-mediated apoptosis. On this basis, it has been proposed that cells lacking MPR are poor targets for cytotoxic lymphocytes that ... More
Fluid-phase markers in the basolateral endocytic pathway accumulate in response to the actin assembly-promoting drug Jasplakinolide.
AuthorsShurety W, Stewart NL, Stow JL
JournalMol Biol Cell
PubMed ID9529391
To investigate the role of filamentous actin in the endocytic pathway, we used the cell-permeant drug Jasplakinolide (JAS) to polymerize actin in intact polarized Madin-Darby canine kidney (MDCK) cells. The uptake and accumulation of the fluid-phase markers fluorescein isothiocyanate (FITC)-dextran and horseradish peroxidase (HRP) were followed in JAS-treated or untreated ... More
Apotransferrin and holotransferrin undergo different endocytic cycles in intestinal epithelia (Caco-2) cells.
AuthorsNúñez MT, Núñez-Millacura C, Beltrán M, Tapia V, Alvarez-Hernandez X
JournalJ Biol Chem
PubMed ID9235943
Previous studies have demonstrated that diferric transferrin and apotransferrin compete for the binding to basolateral transferrin receptors and that transferrin-mediated iron uptake by Caco-2 cells is inhibited by apotransferrin to a larger extent than that predicted solely by receptor competition. This inhibition can have important implications in determining the net ... More
Intracellular routes and selective retention of antigens in mildly acidic cathepsin D/lysosome-associated membrane protein-1/MHC class II-positive vesicles in immature dendritic cells.
Immature dendritic cells (DC) use both macropinocytosis and mannose receptor-mediated endocytosis to internalize soluble Ags efficiently. These Ags are ultimately presented to T cells after DC maturation and migration into the lymph nodes. We have previously described the immortalized myeloid cell line FSDC as displaying the characteristics of early DC ... More
TbVps34, the trypanosome orthologue of Vps34, is required for Golgi complex segregation.
AuthorsHall BS, Gabernet-Castello C, Voak A, Goulding D, Natesan SK, Field MC
JournalJ Biol Chem
PubMed ID16835237
Phosphoinositides are important regulators of numerous cellular functions. The yeast class III phosphatidylinositol 3-kinase Vps34p, and its human orthologue hVPS34, are implicated in control of several key pathways, including endosome to lysosome transport, retrograde endosome to Golgi traffic, multivesicular body formation, and autophagy. We have identified the Vps34p orthologue in ... More
A dominant-negative clathrin mutant differentially affects trafficking of molecules with distinct sorting motifs in the class II major histocompatibility complex (MHC) pathway.
AuthorsLiu SH, Marks MS, Brodsky FM
JournalJ Cell Biol
PubMed ID9490717
The role of clathrin in intracellular sorting was investigated by expression of a dominant-negative mutant form of clathrin, termed the hub fragment. Hub inhibition of clathrin-mediated membrane transport was established by demonstrating a block of transferrin internalization and an alteration in the intracellular distribution of the cation-independent mannose-6-phosphate receptor. Hubs ... More
Chinese hamster ovary cell mutants with temperature-sensitive defects in endocytosis. I. Loss of function on shifting to the nonpermissive temperature.
AuthorsRoff CF, Fuchs R, Mellman I, Robbins AR
JournalJ Cell Biol
PubMed ID2946705
We have isolated three independent Chinese hamster ovary cell mutants (B3853, I223, and M311) with temperature-sensitive, pleiotropic defects in receptor-mediated endocytosis. Activities affected at 41 degrees C include uptake via the D-mannose 6-phosphate receptor, accumulation of Fe from diferric transferrin, uptake of alpha 2-macroglobulin, compartmentalization of newly synthesized acid hydrolases, ... More
Mechanism of transferrin receptor down-regulation in K562 cells in response to protein kinase C activation.
AuthorsSchonhorn JE, Akompong T, Wessling-Resnick M
JournalJ Biol Chem
PubMed ID7876109
Treatment with phorbol esters increases endocytosis of the transferrin receptor in K562 cells (Klausner, R. D., Harford, J., and van Renswoude, J. (1984) Proc. Natl. Acad. Sci. U. S. A. 81, 3005-3009). In this report, we demonstrate that this effect is reversible within early times of protein kinase C activation ... More
Evidence for nonvectorial, retrograde transferrin trafficking in the early endosomes of HEp2 cells.
AuthorsGhosh RN, Maxfield FR
JournalJ Cell Biol
PubMed ID7860630
We have previously characterized the trafficking of transferrin (Tf) through HEp2 human carcinoma cells (Ghosh, R. N., D. L. Gelman, and F. R. Maxfield, 1994. J. Cell Sci. 107:2177-2189). Early endosomes in these cells are comprised of both sorting endosomes and recycling compartments, which are distinct separate compartments. Endocytosed Tf ... More
Quantification of low density lipoprotein and transferrin endocytic sorting HEp2 cells using confocal microscopy.
AuthorsGhosh RN, Gelman DL, Maxfield FR
JournalJ Cell Sci
PubMed ID7983176
Numerous experiments on CHO cells have shown that endosomes are composed of separate vesicular and tubulovesicular compartments, such as the sorting endosome, the recycling compartment, and the late endosome. However, Hopkins et al. (Nature 346, 335-339, 1990) have reported that endosomes in HEp2 human carcinoma cells form an extensive tubular ... More
The epithelial sodium-hydrogen antiporter Na+/H+ exchanger 3 accumulates and is functional in recycling endosomes.
AuthorsD'Souza S, Garcia-Cabado A, Yu F, Teter K, Lukacs G, Skorecki K, Moore HP, Orlowski J, Grinstein S
JournalJ Biol Chem
PubMed ID9442041
Na+/H+ exchangers (NHEs) mediate electroneutral exchange of Na+ for H+ and thereby play a central role in pH regulation and Na+ homeostasis. NHE3, the predominant epithelial isoform, is found in apical membranes of renal and intestinal epithelial cells, where it contributes to NaCl (re)absorption. NHE activity has been detected in ... More
Endocytosis of activated receptors and clathrin-coated pit formation: deciphering the chicken or egg relationship.
AuthorsSantini F, Keen JH
JournalJ Cell Biol
PubMed ID8601582
The fundamental mechanisms by which receptors once targeted for endocytosis are found in coated pits is an important yet unresolved question. Specifically, are activated receptors simply trapped on encountering preexisting coated pits, subsequently being rapidly internalized? Or do the receptors themselves, by active recruitment, gather soluble coat and cytosolic components ... More
Involvement of ATP-dependent Pseudomonas exotoxin translocation from a late recycling compartment in lymphocyte intoxication procedure.
AuthorsAlami M, Taupiac MP, Reggio H, Bienvenüe A, Beaumelle B
JournalMol Biol Cell
PubMed ID9450963
Pseudomonas exotoxin (PE) is a cytotoxin which, after endocytosis, is delivered to the cytosol where it inactivates protein synthesis. Using diaminobenzidine cytochemistry, we found over 94% of internalized PE in transferrin (Tf) -positive endosomes of lymphocytes. When PE translocation was examined in a cell-free assay using purified endocytic vesicles, more ... More
Basolateral to apical transcytosis in polarized cells is indirect and involves BFA and trimeric G protein sensitive passage through the apical endosome.
AuthorsBarroso M, Sztul ES
JournalJ Cell Biol
PubMed ID7905002
We have used temperature and nocodazole blocks in an in vivo basolateral to apical transcytosis assay to dissociate the early transcytotic steps occurring during the formation of transcytotic vesicles and their microtubule-dependent translocation into the apical region, from the late steps when transcytotic cargo is delivered into the apical media. ... More
Involvement of endocytic organelles in the subcellular trafficking and localization of riboflavin.
AuthorsHuang SN, Phelps MA, Swaan PW
JournalJ Pharmacol Exp Ther
PubMed ID12721324
Previous studies by our laboratory have suggested the potential role of receptor-mediated endocytosis components in the cellular translocation of riboflavin (vitamin B2). To delineate the intracellular compartments and events involved in the internalization of riboflavin, we synthesized a rhodamine-labeled riboflavin conjugate to monitor its movement via fluorescent microscopy. Cellular uptake ... More
Oligomerized transferrin receptors are selectively retained by a lumenal sorting signal in a long-lived endocytic recycling compartment.
AuthorsMarsh EW, Leopold PL, Jones NL, Maxfield FR
JournalJ Cell Biol
PubMed ID7790351
Cross-linking of surface receptors results in altered receptor trafficking in the endocytic system. To better understand the cellular and molecular mechanisms by which receptor cross-linking affects the intracellular trafficking of both ligand and receptor, we studied the intracellular trafficking of the transferrin receptor (TfR) bound to multivalent-transferrin (Tf10) which was ... More
Cholesterol derivative of poly(ethylene glycol) inhibits clathrin-independent, but not clathrin-dependent endocytosis.
AuthorsIshiwata H, Sato SB, Vertut-Doï A, Hamashima Y, Miyajima K
JournalBiochim Biophys Acta
PubMed ID9409809
The effect of poly(ethylene glycol) cholesteryl ethers (PEG(n)-Chols) with two different numbers of units (n = 50 and 200) in the hydrophilic PEG moiety on cellular endocytic activity was studied on HT-1080 cells. The amphipathic molecules were soluble in aqueous solution. When fluorescein derivatives of PEG-Chols (one fluorescein at the ... More
Cellular uptake of exogenous human PDCD5 protein.
AuthorsWang Y, Li D, Fan H, Tian L, Zhong Y, Zhang Y, Yuan L, Jin C, Yin C, Ma D
JournalJ Biol Chem
PubMed ID16754680
PDCD5 (human programmed cell death 5) plays a significant role in apoptotic and paraptotic cell deaths. However, it was found that recombinant PDCD5 added exogenously to culture medium could also enhance programmed cell death triggered by certain stimuli. Here we show that PDCD5 has a remarkable role in intercellular transport ... More
Cellubrevin-targeted fluorescence uncovers heterogeneity in the recycling endosomes.
AuthorsTeter K, Chandy G, Quiñones B, Pereyra K, Machen T, Moore HP
JournalJ Biol Chem
PubMed ID9677389
The pH and trafficking of recycling endosomes have previously been studied using transferrin. We have used another approach, one in which the vesicle transport protein cellubrevin was appended with a luminal IgG epitope to allow targeting of fluorescein-5'-isothiocyanate (FITC)-labeled anti-IgG F(ab) antibodies to the recycling endosomes in living cells. FITC-F(ab) ... More
Mobilization of iron from endocytic vesicles. The effects of acidification and reduction.
AuthorsNúñez MT, Gaete V, Watkins JA, Glass J
JournalJ Biol Chem
PubMed ID2324097
The factors necessary to dissociate iron from transferrin in endocytic vesicles and to mobilize the iron across the vesicle membrane were studied in a preparation of endocytic vesicles markedly enriched in transferrin-transferrin receptor complexes isolated from rabbit reticulocytes. Vesicles were prepared with essentially fully saturated transferrin by incubating the reticulocytes ... More
Lysosomes behave as Ca2+-regulated exocytic vesicles in fibroblasts and epithelial cells.
AuthorsRodríguez A, Webster P, Ortego J, Andrews NW
JournalJ Cell Biol
PubMed ID9105039
Lysosomes are considered to be a terminal degradative compartment of the endocytic pathway, into which transport is mostly unidirectional. However, specialized secretory vesicles regulated by Ca2+, such as neutrophil azurophil granules, mast cell-specific granules, and cytotoxic lymphocyte lytic granules, share characteristics with lysosomes that may reflect a common biogenesis. In ... More
Modulation of cellular iron metabolism by hydrogen peroxide. Effects of H2O2 on the expression and function of iron-responsive element-containing mRNAs in B6 fibroblasts.
AuthorsCaltagirone A, Weiss G, Pantopoulos K
JournalJ Biol Chem
PubMed ID11264285
Cellular iron uptake and storage are coordinately controlled by binding of iron-regulatory proteins (IRP), IRP1 and IRP2, to iron-responsive elements (IREs) within the mRNAs encoding transferrin receptor (TfR) and ferritin. Under conditions of iron starvation, both IRP1 and IRP2 bind with high affinity to cognate IREs, thus stabilizing TfR and ... More
Endocytosis of ligand-human parathyroid hormone receptor 1 complexes is protein kinase C-dependent and involves beta-arrestin2. Real-time monitoring by fluorescence microscopy.
AuthorsFerrari SL, Behar V, Chorev M, Rosenblatt M, Bisello A
JournalJ Biol Chem
PubMed ID10514480
Endocytosis and intracellular trafficking of the human parathyroid hormone receptor subtype 1 (hPTH1-Rc) and its ligands was monitored independently by real-time fluorescence microscopy in stably transfected HEK-293 cells. Complexes of fluorescence-labeled parathyroid hormone (PTH)-(1-34) agonist bound to the hPTH1-Rc internalized rapidly at 37 degrees C via clathrin-coated vesicles, whereas fluorescent ... More
Role of COPI in phagosome maturation.
AuthorsBotelho RJ, Hackam DJ, Schreiber AD, Grinstein S
JournalJ Biol Chem
PubMed ID10748188
Phagosomes mature by sequentially fusing with endosomes and lysosomes. Vesicle budding is presumed to occur concomitantly, mediating the retrieval of plasmalemmal components and the regulation of phagosomal size. We analyzed whether fission of vesicles from phagosomes requires COPI, a multimeric complex known to be involved in budding from the Golgi ... More
Age-dependency of molecular diffusion in the human anterior lens capsule assessed using fluorescence recovery after photobleaching.
Authors
JournalMol Vis
PubMed ID31741652
HRS-WASH axis governs actin-mediated endosomal recycling and cell invasion.
Authors
JournalJ Cell Biol
PubMed ID29891722
Brain-specific Drp1 regulates postsynaptic endocytosis and dendrite formation independently of mitochondrial division.
Authors
JournalElife
PubMed ID31603426
Apolipoprotein A-I Crosses the Blood-Brain Barrier through Clathrin-Independent and Cholesterol-Mediated Endocytosis.
Authors
JournalJ Pharmacol Exp Ther
PubMed ID30971477
An in vivo screen identifies ependymoma oncogenes and tumor-suppressor genes.