Temporal and spatial distribution of activated Pak1 in fibroblasts.
AuthorsSells MA, Pfaff A, Chernoff J
JournalJ Cell Biol
PubMed ID11134074
'p21-activated kinases (Paks) are effectors of the small GTPases Cdc42 and Rac, and are thought to mediate some of the cytoskeletal and transcriptional activities of these proteins. To localize activated Pak1 in cells, we developed an antibody directed against a phosphopeptide that is contained within the activation loop of Pak1. ... More
Apical, lateral, and basal polarization cues contribute to the development of the follicular epithelium during Drosophila oogenesis.
AuthorsTanentzapf G, Smith C, McGlade J, Tepass U
JournalJ Cell Biol
PubMed ID11076972
'Analysis of the mechanisms that control epithelial polarization has revealed that cues for polarization are mediated by transmembrane proteins that operate at the apical, lateral, or basal surface of epithelial cells. Whereas for any given epithelial cell type only one or two polarization systems have been identified to date, we ... More
Modulation of acto-myosin contractility in skeletal muscle myoblasts uncouples growth arrest from differentiation.
AuthorsDhawan J, Helfman DM
JournalJ Cell Sci
PubMed ID15252113
'Cell-substratum interactions trigger key signaling pathways that modulate growth control and tissue-specific gene expression. We have previously shown that abolishing adhesive interactions by suspension culture results in G(0) arrest of myoblasts. We report that blocking intracellular transmission of adhesion-dependent signals in adherent cells mimics the absence of adhesive contacts. We ... More
Lipid rafts in the maintenance of synapses, dendritic spines, and surface AMPA receptor stability.
AuthorsHering H, Lin CC, Sheng M
JournalJ Neurosci
PubMed ID12716933
'Cholesterol/sphingolipid microdomains (lipid rafts) in the membrane are involved in protein trafficking, formation of signaling complexes, and regulation of actin cytoskeleton. Here, we show that lipid rafts exist abundantly in dendrites of cultured hippocampal neurons, in which they are associated with several postsynaptic proteins including surface AMPA receptors. Depletion of ... More
ADP-ribosylation factor 6 regulates a novel plasma membrane recycling pathway.
AuthorsRadhakrishna H, Donaldson JG
JournalJ Cell Biol
PubMed ID9314528
'ADP-ribosylation factor (ARF) 6 localizes to the plasma membrane (PM) in its GTP state and to a tubulovesicular compartment in its GDP state in HeLa cells that express wild-type or mutant forms of this GTPase. Aluminum fluoride (AlF) treatment of ARF6-transfected cells redistributes ARF6 to the PM and stimulates the ... More
Role of the cytoskeleton in mediating cAMP-dependent protein kinase inhibition of the epithelial Na+/H+ exchanger NHE3.
'The Na(+)/H(+) exchanger NHE3 isoform mediates the entry of Na(+) into epithelial cells of the kidney and gastrointestinal tract. Hormones and pharmacological agents that activate cAMP-dependent protein kinase A (PKA) are potent inhibitors of native and ectopically expressed NHE3 in epithelial and Chinese hamster ovary AP-1 cells, respectively. Previous studies ... More
The effects of osmotic stress on the viscoelastic and physical properties of articular chondrocytes.
AuthorsGuilak F, Erickson GR, Ting-Beall HP
JournalBiophys J
PubMed ID11806914
'The metabolic activity of chondrocytes in articular cartilage is influenced by alterations in the osmotic environment of the tissue, which occur secondary to mechanical compression. The mechanism by which osmotic stress modulates cell physiology is not fully understood and may involve changes in the physical properties of the membrane or ... More
VAMP2, but not VAMP3/cellubrevin, mediates insulin-dependent incorporation of GLUT4 into the plasma membrane of L6 myoblasts.
AuthorsRandhawa VK, Bilan PJ, Khayat ZA, Daneman N, Liu Z, Ramlal T, Volchuk A, Peng XR, Coppola T, Regazzi R, Trimble WS, Klip A
JournalMol Biol Cell
PubMed ID10888677
'Like neuronal synaptic vesicles, intracellular GLUT4-containing vesicles must dock and fuse with the plasma membrane, thereby facilitating insulin-regulated glucose uptake into muscle and fat cells. GLUT4 colocalizes in part with the vesicle SNAREs VAMP2 and VAMP3. In this study, we used a single-cell fluorescence-based assay to compare the functional involvement ... More
ADPKD: a human disease altering Golgi function and basolateral exocytosis in renal epithelia.
AuthorsCharron AJ, Bacallao RL, Wandinger-Ness A
JournalTraffic
PubMed ID11208155
'Epithelial cells explanted from autosomal dominant polycystic kidney disease (ADPKD) tissue exhibit impaired exocytosis, specifically between the Golgi and basolateral membrane (Charron A, Nakamura B, Bacallo R, Wandinger-Ness A. Compromised cytoarchitecture and polarized trafficking in autosomal dominant polycystic kidney disease cells. J Cell Biol 2000; 148: 111-124.). Here the defect ... More
Actin-binding verprolin is a polarity development protein required for the morphogenesis and function of the yeast actin cytoskeleton.
AuthorsVaduva G, Martin NC, Hopper AK
JournalJ Cell Biol
PubMed ID9412475
'Yeast verprolin, encoded by VRP1, is implicated in cell growth, cytoskeletal organization, endocytosis and mitochondrial protein distribution and function. We show that verprolin is also required for bipolar bud-site selection. Previously we reported that additional actin suppresses the temperature-dependent growth defect caused by a mutation in VRP1. Here we show ... More
Filopodia that extend from neuronal growth cones sample the environment for extracellular guidance cues, but the signals they transmit to growth cones are unknown. Filopodia were observed generating localized transient elevations of intracellular calcium ([Ca2+]i) that propagate back to the growth cone and stimulate global Ca2+ elevations. The frequency of ... More
The Alzheimer amyloid precursor protein (APP) and FE65, an APP-binding protein, regulate cell movement.
AuthorsSabo SL, Ikin AF, Buxbaum JD, Greengard P
JournalJ Cell Biol
PubMed ID11425871
FE65 binds to the Alzheimer amyloid precursor protein (APP), but the function of this interaction has not been identified. Here, we report that APP and FE65 are involved in regulation of cell movement. APP and FE65 colocalize with actin and Mena, an Abl-associated signaling protein thought to regulate actin dynamics, ... More
Fluorescence measurements of serotonin-induced V-ATPase-dependent pH changes at the luminal surface in salivary glands of the blowfly Calliphora vicina.
AuthorsRein J, Zimmermann B, Hille C, Lang I, Walz B, Baumann O,
JournalJ Exp Biol
PubMed ID16621952
Secretion in blowfly salivary glands is induced by the neurohormone serotonin and powered by a vacuolar-type H(+)-ATPase (V-ATPase) located in the apical membrane of the secretory cells. We have established a microfluorometric method for analysing pH changes at the luminal surface of the secretory epithelial cells by using the fluorescent ... More
Dual stimulation of Ras/mitogen-activated protein kinase and RhoA by cell adhesion to fibronectin supports growth factor-stimulated cell cycle progression.
AuthorsDanen EH, Sonneveld P, Sonnenberg A, Yamada KM
JournalJ Cell Biol
PubMed ID11134071
In cellular transformation, activated forms of the small GTPases Ras and RhoA can cooperate to drive cells through the G1 phase of the cell cycle. Here, we show that a similar but substrate-regulated mechanism is involved in the anchorage-dependent proliferation of untransformed NIH-3T3 cells. Among several extracellular matrix components tested, ... More
Metabolic installation of thiols into sialic acid modulates adhesion and stem cell biology.
AuthorsSampathkumar SG, Li AV, Jones MB, Sun Z, Yarema KJ
JournalNat Chem Biol
PubMed ID16474386
Metabolic 'oligosaccharide engineering' methods based on N-acetyl-D-mannosamine (ManNAc) analogs allow the glycocalyx of living cells to be remodeled. Herein we report the analog Ac(5)ManNTGc (1) that enables thiols to be expressed in surface sialic acids. By locating this versatile functional group on the outer periphery of normally nonadhesive human Jurkat ... More
GTPases and phosphatidylinositol 3-kinase are critical for insulin-like growth factor-I-mediated Schwann cell motility.
AuthorsCheng HL, Steinway ML, Russell JW, Feldman EL
JournalJ Biol Chem
PubMed ID10829021
Previously, we reported insulin-like growth factor-I (IGF-I) promotes motility and focal adhesion kinase (FAK) activation in neuronal cells. In the current study, we examined the role of IGF-I in Schwann cell (SC) motility. IGF-I increases SC process extension and motility. In parallel, IGF-I activates IGF-I receptor, insulin receptor substrate-1 (IRS-1), ... More
The human WASP-interacting protein, WIP, activates the cell polarity pathway in yeast.
AuthorsVaduva G, Martinez-Quiles N, Anton IM, Martin NC, Geha RS, Hopper AK, Ramesh N
JournalJ Biol Chem
PubMed ID10358064
WIP, the Wiskott-Aldrich syndrome protein-interacting protein, is a human protein involved in actin polymerization and redistribution in lymphoid cells. The mechanism by which WIP reorganizes actin cytoskeleton is unknown. WIP is similar to yeast verprolin, an actin- and myosin-interacting protein required for polarized morphogenesis. To determine whether WIP and verprolin ... More
Reversible glutathionylation regulates actin polymerization in A431 cells.
AuthorsWang J, Boja ES, Tan W, Tekle E, Fales HM, English S, Mieyal JJ, Chock PB
JournalJ Biol Chem
PubMed ID11684673
In response to growth factor stimulation, many mammalian cells transiently generate reactive oxygen species (ROS) that lead to the elevation of tyrosine-phosphorylated and glutathionylated proteins. While investigating EGF-induced glutathionylation in A431 cells, paradoxically we found deglutathionylation of a major 42-kDa protein identified as actin. Mass spectrometric analysis revealed that the ... More
Role of actin cortex in the subplasmalemmal transport of secretory granules in PC-12 cells.
AuthorsLang T, Wacker I, Wunderlich I, Rohrbach A, Giese G, Soldati T, Almers W
JournalBiophys J
PubMed ID10827968
In neuroendocrine PC-12 cells, evanescent-field fluorescence microscopy was used to track motions of green fluorescent protein (GFP)-labeled actin or GFP-labeled secretory granules in a thin layer of cytoplasm where cells adhered to glass. The layer contained abundant filamentous actin (F-actin) locally condensed into stress fibers. More than 90% of the ... More
Extraction of near-field fluorescence from composite signals to provide high resolution images of glial cells.
AuthorsDoyle RT, Szulzcewski MJ, Haydon PG
JournalBiophys J
PubMed ID11325746
The subdiffraction optical resolution that can be achieved using near-field optical microscopy has the potential to permit new approaches and insights into subcellular function and molecular dynamics. Despite the potential of this technology, it has been difficult to apply to cellular samples. One significant problem is that sample thickness causes ... More
Keratocytes pull with similar forces on their dorsal and ventral surfaces.
AuthorsGalbraith CG, Sheetz MP
JournalJ Cell Biol
PubMed ID10601343
As cells move forward, they pull rearward against extracellular matrices (ECMs), exerting traction forces. However, no rearward forces have been seen in the fish keratocyte. To address this discrepancy, we have measured the propulsive forces generated by the keratocyte lamella on both the ventral and the dorsal surfaces. On the ... More
Serum response factor is crucial for actin cytoskeletal organization and focal adhesion assembly in embryonic stem cells.
AuthorsSchratt G, Philippar U, Berger J, Schwarz H, Heidenreich O, Nordheim A
JournalJ Cell Biol
PubMed ID11839767
The activity of serum response factor (SRF), an essential transcription factor in mouse gastrulation, is regulated by changes in actin dynamics. Using Srf(-/-) embryonic stem (ES) cells, we demonstrate that SRF deficiency causes impairments in ES cell spreading, adhesion, and migration. These defects correlate with defective formation of cytoskeletal structures, ... More
The apical Na(+)/H(+) exchanger isoform NHE3 is regulated by the actin cytoskeleton.
The epithelial isoform of the Na(+)/H(+) exchanger, NHE3, associates with at least two related regulatory factors called NHERF1/EBP50 and NHERF2/TKA-1/E3KARP. These factors in addition interact with the cytoskeletal protein ezrin, which in turn binds to actin. The possible linkage of NHE3 with the cytoskeleton prompted us to test the effect ... More
Inhibition of calpain blocks platelet secretion, aggregation, and spreading.
AuthorsCroce K, Flaumenhaft R, Rivers M, Furie B, Furie BC, Herman IM, Potter DA
JournalJ Biol Chem
PubMed ID10593923
Previous studies have indicated that the Ca(2+)-dependent protease, calpain, is activated in platelets within 30-60 s of thrombin stimulation, but specific roles of calpain in platelets remain to be identified. To directly test the functions of calpain during platelet activation, a novel strategy was developed for introducing calpain's specific biological ... More
Reorganization of cytoskeleton during surfactant secretion in lung type II cells: a role of annexin II.
AuthorsSingh TK, Abonyo B, Narasaraju TA, Liu L
JournalCell Signal
PubMed ID14607276
The secretion of lung surfactant requires the movement of lamellar bodies to the plasma membrane through cytoskeletal barrier at the cell cortex. We hypothesized that the cortical cytoskeleton undergoes a transient disassembly/reassembly in the stimulated type II cells, therefore allowing lamellar bodies access to the plasma membrane. Stabilization of cytoskeleton ... More
cAMP-dependent protein kinase phosphorylation of EVL, a Mena/VASP relative, regulates its interaction with actin and SH3 domains.
AuthorsLambrechts A, Kwiatkowski AV, Lanier LM, Bear JE, Vandekerckhove J, Ampe C, Gertler FB
JournalJ Biol Chem
PubMed ID10945997
Proteins of the Ena/VASP family are implicated in processes that require dynamic actin remodeling such as axon guidance and platelet activation. In this work, we explored some of the pathways that likely regulate actin dynamics in part via EVL (Ena/VASP-like protein). Two isoforms, EVL and EVL-I, were highly expressed in ... More
DE-Cadherin is required for intercellular motility during Drosophila oogenesis.
AuthorsNiewiadomska P, Godt D, Tepass U
JournalJ Cell Biol
PubMed ID9971747
Cadherins are involved in a variety of morphogenetic movements during animal development. However, it has been difficult to pinpoint the precise function of cadherins in morphogenetic processes due to the multifunctional nature of cadherin requirement. The data presented here indicate that homophilic adhesion promoted by Drosophila E-cadherin (DE-cadherin) mediates two ... More
Visualization of melanosome dynamics within wild-type and dilute melanocytes suggests a paradigm for myosin V function In vivo.
AuthorsWu X, Bowers B, Rao K, Wei Q, Hammer JA
JournalJ Cell Biol
PubMed ID9864363
Unlike wild-type mouse melanocytes, where melanosomes are concentrated in dendrites and dendritic tips, melanosomes in dilute (myosin Va-) melanocytes are concentrated in the cell center. Here we sought to define the role that myosin Va plays in melanosome transport and distribution. Actin filaments that comprise a cortical shell running the ... More
PYK2 autophosphorylation, but not kinase activity, is necessary for adhesion-induced association with c-Src, osteoclast spreading, and bone resorption.
AuthorsLakkakorpi PT, Bett AJ, Lipfert L, Rodan GA, Duong le T
JournalJ Biol Chem
PubMed ID12514172
Proline-rich tyrosine kinase 2 (PYK2) is the main adhesion-induced kinase in bone-resorbing osteoclasts. Previous studies have shown that ligation of alpha(v)beta(3) integrin in osteoclasts induces c-Src-dependent tyrosine phosphorylation and PYK2 activation, leading to cytoskeletal rearrangement, migration, and polarization of these cells. In this study, we examined the role of PYK2 ... More
Preparation and evaluation of human choroid extracellular matrix scaffolds for the study of cell replacement strategies.
Authors
JournalActa Biomater
PubMed ID28483697
Engineering human pluripotent stem cells into a functional skeletal muscle tissue.
Authors
JournalNat Commun
PubMed ID29317646
A novel function for Rab1 and Rab11 during secretory granule maturation.
Authors
JournalJ Cell Sci
PubMed ID34342349
Heterogeneous Responses to Mechanical Force of Prostate Cancer Cells Inducing Different Metastasis Patterns.
Authors
JournalAdv Sci (Weinh)
PubMed ID32775149
Transient acidification and subsequent proinflammatory cytokine stimulation of astrocytes induce distinct activation phenotypes.
Authors
JournalJ Cell Physiol
PubMed ID23154943
PAK4 methylation by the methyltransferase SETD6 attenuates cell adhesion.
Authors
JournalSci Rep
PubMed ID33051544
Moderate strength (0.23-0.28 T) static magnetic fields (SMF) modulate signaling and differentiation in human embryonic cells.
Authors
JournalBMC Genomics
PubMed ID19653909
Cereulide and Deoxynivalenol Increase LC3 Protein Levels in HepG2 Liver Cells.
Authors
JournalToxins (Basel)
PubMed ID35202179
Cell alignment using patterned biocompatible gold nanoparticle templates.
Authors
JournalSmall
PubMed ID22354857
A novel function for Rab1 and Rab11 during secretory granule maturation.