Intimin types alpha, beta, and gamma bind to nucleolin with equivalent affinity but lower avidity than to the translocated intimin receptor.
AuthorsSinclair JF, O'Brien AD
JournalJ Biol Chem
PubMed ID15173179
The outer membrane adhesins of enteropathogenic Escherichia coli, Citrobacter rodentium, and enterohemorrhagic E. coli (EHEC) O157:H7 that mediate attach and efface intestinal lesions are classified as intimin alpha, beta, and gamma, respectively. Each of these intimin types binds to its cognate, bacterially encoded receptor (called Tir for translocated intimin receptor) ... More
UGO1 encodes an outer membrane protein required for mitochondrial fusion.
AuthorsSesaki H, Jensen RE
JournalJ Cell Biol
PubMed ID11257114
'Membrane fusion plays an important role in controlling the shape, number, and distribution of mitochondria. In the yeast Saccharomyces cerevisiae, the outer membrane protein Fzo1p has been shown to mediate mitochondrial fusion. Using a novel genetic screen, we have isolated new mutants defective in the fusion of their mitochondria. One ... More
LIM kinase 2 is widely expressed in all tissues.
AuthorsAcevedo K, Moussi N, Li R, Soo P, Bernard O
JournalJ Histochem Cytochem
PubMed ID16399995
'The LIM kinase family includes two proteins: LIMK1 and LIMK2. These proteins have identical genomic structure and overall amino acid identity of 50%. Both proteins regulate actin polymerization via phosphorylation and inactivation of the actin depolymerizing factors ADF/cofilin. Although the function of endogenous LIMK1 is well established, little is known ... More
Essential role of CIB1 in regulating PAK1 activation and cell migration.
AuthorsLeisner TM, Liu M, Jaffer ZM, Chernoff J, Parise LV
JournalJ Cell Biol
PubMed ID16061695
'p21-activated kinases (PAKs) regulate many cellular processes, including cytoskeletal rearrangement and cell migration. In this study, we report a direct and specific interaction of PAK1 with a 22-kD Ca2+-binding protein, CIB1, which results in PAK1 activation both in vitro and in vivo. CIB1 binds to PAK1 within discrete regions surrounding ... More
Cleavage and shedding of E-cadherin after induction of apoptosis.
AuthorsSteinhusen U, Weiske J, Badock V, Tauber R, Bommert K, Huber O
JournalJ Biol Chem
PubMed ID11076937
'Apoptotic cell death induces dramatic molecular changes in cells, becoming apparent on the structural level as membrane blebbing, condensation of the cytoplasm and nucleus, and loss of cell-cell contacts. The activation of caspases is one of the fundamental steps during programmed cell death. Here we report a detailed analysis of ... More
Multiphoton excitation spectra in biological samples.
AuthorsDickinson ME, Simbuerger E, Zimmermann B, Waters CW, Fraser SE
JournalJ Biomed Opt
PubMed ID12880336
'Multiphoton microscopy is becoming a popular mode of live and fixed cell imaging. This mode of imaging offers several advantages due to the fact that fluorochrome excitation is a nonlinear event resulting in excitation only at the plane of focus. Multiphoton excitation is enhanced by the use of ultrafast lasers ... More
The Saccharomyces cerevisiae homologue of human Wiskott-Aldrich syndrome protein Las17p interacts with the Arp2/3 complex.
AuthorsMadania A, Dumoulin P, Grava S, Kitamoto H, Schärer-Brodbeck C, Soulard A, Moreau V, Winsor B
JournalMol Biol Cell
PubMed ID10512884
'Yeast Las17 protein is homologous to the Wiskott-Aldrich Syndrome protein, which is implicated in severe immunodeficiency. Las17p/Bee1p has been shown to be important for actin patch assembly and actin polymerization. Here we show that Las17p interacts with the Arp2/3 complex. LAS17 is an allele-specific multicopy suppressor of ARP2 and ARP3 ... More
The carboxyl terminus of the alpha-subunit of the amiloride-sensitive epithelial sodium channel binds to F-actin.
AuthorsMazzochi C, Bubien JK, Smith PR, Benos DJ
JournalJ Biol Chem
PubMed ID16356937
'The activity of the amiloride-sensitive epithelial sodium channel (ENaC) is modulated by F-actin. However, it is unknown if there is a direct interaction between alpha-ENaC and actin. We have investigated the hypothesis that the actin cytoskeleton directly binds to the carboxyl terminus of alpha-ENaC using a combination of confocal microscopy, ... More
TGF-beta1 + EGF-initiated invasive potential in transformed human keratinocytes is coupled to a plasmin/MMP-10/MMP-1-dependent collagen remodeling axis: role for PAI-1.
AuthorsWilkins-Port CE, Ye Q, Mazurkiewicz JE, Higgins PJ,
JournalCancer Res
PubMed ID19383899
'The phenotypic switching called epithelial-to-mesenchymal transition is frequently associated with epithelial tumor cell progression from a comparatively benign to an aggressive, invasive malignancy. Coincident with the emergence of such cellular plasticity is an altered response to transforming growth factor-beta (TGF-beta) as well as epidermal growth factor (EGF) receptor amplification. TGF-beta ... More
Disabling poxvirus pathogenesis by inhibition of Abl-family tyrosine kinases.
AuthorsReeves PM, Bommarius B, Lebeis S, McNulty S, Christensen J, Swimm A, Chahroudi A, Chavan R, Feinberg MB, Veach D, Bornmann W, Sherman M, Kalman D
JournalNat Med
PubMed ID15980865
'The Poxviridae family members vaccinia and variola virus enter mammalian cells, replicate outside the nucleus and produce virions that travel to the cell surface along microtubules, fuse with the plasma membrane and egress from infected cells toward apposing cells on actin-filled membranous protrusions. We show that cell-associated enveloped virions (CEV) ... More
Subcellular positioning of small molecules.
AuthorsTakayama S, Ostuni E, LeDuc P, Naruse K, Ingber DE, Whitesides GM
JournalNature
PubMed ID11429594
Single-molecule speckle analysis of actin filament turnover in lamellipodia.
AuthorsWatanabe N, Mitchison TJ
JournalScience
PubMed ID11834838
'Lamellipodia are thin, veil-like extensions at the edge of cells that contain a dynamic array of actin filaments. We describe an approach for analyzing spatial regulation of actin polymerization and depolymerization in vivo in which we tracked single molecules of actin fused to the green fluorescent protein. Polymerization and the ... More
RanBP10 is a cytoplasmic guanine nucleotide exchange factor that modulates noncentrosomal microtubules.
AuthorsSchulze H, Dose M, Korpal M, Meyer I, Italiano JE, Shivdasani RA,
JournalJ Biol Chem
PubMed ID18347012
'Microtubule spindle assembly in mitosis is stimulated by Ran.GTP, which is generated along condensed chromosomes by the guanine nucleotide exchange factor (GEF) RCC1. This relationship suggests that similar activities might modulate other microtubule structures. Interphase microtubules usually extend from the centrosome, although noncentrosomal microtubules function in some differentiated cells, including ... More
Rac1 orientates epithelial apical polarity through effects on basolateral laminin assembly.
AuthorsO'Brien LE, Jou TS, Pollack AL, Zhang Q, Hansen SH, Yurchenco P, Mostov KE
JournalNat Cell Biol
PubMed ID11533663
'Cellular polarization involves the generation of asymmetry along an intracellular axis. In a multicellular tissue, the asymmetry of individual cells must conform to the overlying architecture of the tissue. However, the mechanisms that couple cellular polarization to tissue morphogenesis are poorly understood. Here, we report that orientation of apical polarity ... More
Shiga toxin of enterohemorrhagic Escherichia coli type O157:H7 promotes intestinal colonization.
AuthorsRobinson CM, Sinclair JF, Smith MJ, O'Brien AD
JournalProc Natl Acad Sci U S A
PubMed ID16766659
Enterohemorrhagic Escherichia coli (EHEC) 0157:H7 is a food-borne pathogen that can cause bloody diarrhea and, occasionally, acute renal failure as a consequence of Shiga toxin (Stx) production by the organism. Stxs are potent cytotoxins that are lethal to animals at low doses. Thus, Stxs not only harm the host but, ... More
Regulation of phagosome maturation by signals from toll-like receptors.
AuthorsBlander JM, Medzhitov R
JournalScience
PubMed ID15143282
In higher metazoans, phagocytosis is essential in host defense against microbial pathogens and in clearance of apoptotic cells. Both microbial and apoptotic cells are delivered on a common route from phagosomes to lysosomes for degradation. Here, we found that activation of the Toll-like receptor (TLR) signaling pathway by bacteria, but ... More
Distinct roles of TIR and non-TIR regions in the subcellular localization and signaling properties of MyD88.
AuthorsNishiya T, Kajita E, Horinouchi T, Nishimoto A, Miwa S,
JournalFEBS Lett
PubMed ID17583698
MyD88 is a cytoplasmic adaptor protein that is critical for Toll-like receptor (TLR) signaling. The subcellular localization of MyD88 is characterized as large condensed forms in the cytoplasm. The mechanism and significance of this localization with respect to the signaling function, however, are currently unknown. Here, we demonstrate that MyD88 ... More
EphA receptors regulate growth cone dynamics through the novel guanine nucleotide exchange factor ephexin.
AuthorsShamah SM, Lin MZ, Goldberg JL, Estrach S, Sahin M, Hu L, Bazalakova M, Neve RL, Corfas G, Debant A, Greenberg ME
JournalCell
PubMed ID11336673
Eph receptors transduce short-range repulsive signals for axon guidance by modulating actin dynamics within growth cones. We report the cloning and characterization of ephexin, a novel Eph receptor-interacting protein that is a member of the Dbl family of guanine nucleotide exchange factors (GEFs) for Rho GTPases. Ephrin-A stimulation of EphA ... More
Control of Actin Reorganization by Slingshot, a Family of Phosphatases that Dephosphorylate ADF/Cofilin.
The ADF (actin-depolymerizing factor)/cofilin family is a stimulus-responsive mediator of actin dynamics. In contrast to the mechanisms of inactivation of ADF/cofilin by kinases such as LIM-kinase 1 (LIMK1), much less is known about its reactivation through dephosphorylation. Here we report Slingshot (SSH), a family of phosphatases that have the property ... More
Requirements of SLP76 tyrosines in ITAM and integrin receptor signaling and in platelet function in vivo.
AuthorsBezman NA, Lian L, Abrams CS, Brass LF, Kahn ML, Jordan MS, Koretzky GA,
JournalJ Exp Med
PubMed ID18663126
Src homology 2 domain-containing leukocyte phosphoprotein of 76 kD (SLP76), an adaptor that plays a critical role in platelet activation in vitro, contains three N-terminal tyrosine residues that are essential for its function. We demonstrate that mice containing complementary tyrosine to phenylalanine mutations in Y145 (Y145F) and Y112 and Y128 ... More
Coordinated cell-shape changes control epithelial movement in zebrafish and Drosophila.
AuthorsKöppen M, Fernández BG, Carvalho L, Jacinto A, Heisenberg CP,
JournalDevelopment
PubMed ID16794032
Epithelial morphogenesis depends on coordinated changes in cell shape, a process that is still poorly understood. During zebrafish epiboly and Drosophila dorsal closure, cell-shape changes at the epithelial margin are of critical importance. Here evidence is provided for a conserved mechanism of local actin and myosin 2 recruitment during theses ... More
A human CXCL13-induced actin polymerization assay measured by fluorescence plate reader.
AuthorsAlley J, Bloom L, Kasaian M, Gao H, Berstein G, Clark JD, Miao W,
JournalAssay Drug Dev Technol
PubMed ID20085454
The chemokine receptor CXCR5 is predominantly expressed on mature B cells and follicular T-helper cells. CXCR5 and its ligand CXCL13 participate in ectopic germinal center formation at the inflammatory sites of multiple immune diseases such as rheumatoid arthritis, multiple sclerosis, and Sjogren's syndrome. Therefore, disrupting CXCL13-induced chemotaxis may be a ... More
Defining mechanisms of actin polymerization and depolymerization during dendritic spine morphogenesis.
Dendritic spines are small protrusions along dendrites where the postsynaptic components of most excitatory synapses reside in the mature brain. Morphological changes in these actin-rich structures are associated with learning and memory formation. Despite the pivotal role of the actin cytoskeleton in spine morphogenesis, little is known about the mechanisms ... More
The membrane-anchored metalloproteinase regulator RECK stabilizes focal adhesions and anterior-posterior polarity in fibroblasts.
AuthorsMorioka Y, Monypenny J, Matsuzaki T, Shi S, Alexander DB, Kitayama H, Noda M,
JournalOncogene
PubMed ID19169281
Accumulating evidence indicates that Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a membrane-anchored matrix metalloproteinase regulator, plays crucial roles in mammalian development and tumor suppression. Its mechanisms of action at the single cell level, however, remain largely unknown. In mouse fibroblasts, RECK is abundant around the perinuclear region, membrane ruffles ... More
Selective chemical treatment of cellular microdomains using multiple laminar streams.
AuthorsTakayama S, Ostuni E, LeDuc P, Naruse K, Ingber DE, Whitesides GM
JournalChem Biol
PubMed ID12618184
There are many experiments in which it would be useful to treat a part of the surface or interior of a cell with a biochemical reagent. It is difficult, however, to achieve subcellular specificity, because small molecules diffuse distances equal to the extent of the cell in seconds. This paper ... More
Consequences of the selective blockage of chaperone-mediated autophagy.
AuthorsMassey AC, Kaushik S, Sovak G, Kiffin R, Cuervo AM
JournalProc Natl Acad Sci U S A
PubMed ID16585521
Chaperone-mediated autophagy (CMA) is a selective pathway for the degradation of cytosolic proteins in lysosomes. CMA declines with age because of a decrease in the levels of lysosome-associated membrane protein (LAMP) type 2A, a lysosomal receptor for this pathway. We have selectively blocked the expression of LAMP-2A in mouse fibroblasts ... More
P21-activated kinase 1: convergence point in PDGF- and LPA-stimulated collagen matrix contraction by human fibroblasts.
AuthorsRhee S, Grinnell F
JournalJ Cell Biol
PubMed ID16449192
Fibroblast three-dimensional collagen matrix culture provides a tissue-like model that can be used to analyze cell form and function. The physiological agonists platelet-derived growth factor (PDGF) and lysophosphatidic acid (LPA) both stimulate human fibroblasts to contract floating collagen matrices. In this study, we show that the PDGF and LPA signaling ... More
Ups1p, a conserved intermembrane space protein, regulates mitochondrial shape and alternative topogenesis of Mgm1p.
AuthorsSesaki H, Dunn CD, Iijima M, Shepard KA, Yaffe MP, Machamer CE, Jensen RE
JournalJ Cell Biol
PubMed ID16754953
Mgm1p is a conserved dynamin-related GTPase required for fusion, morphology, inheritance, and the genome maintenance of mitochondria in Saccharomyces cerevisiae. Mgm1p undergoes unconventional processing to produce two functional isoforms by alternative topogenesis. Alternative topogenesis involves bifurcate sorting in the inner membrane and intramembrane proteolysis by the rhomboid protease Pcp1p. Here, ... More
Par-3 mediates the inhibition of LIM kinase 2 to regulate cofilin phosphorylation and tight junction assembly.
AuthorsChen X, Macara IG
JournalJ Cell Biol
PubMed ID16505165
The polarity protein Par-3 plays critical roles in axon specification and the establishment of epithelial apico-basal polarity. Par-3 associates with Par-6 and atypical protein kinase C and is required for the proper assembly of tight junctions, but the molecular basis for its functions is poorly understood. We now report that ... More
RhoA and ROCK promote migration by limiting membrane protrusions.
AuthorsWorthylake RA, Burridge K
JournalJ Biol Chem
PubMed ID12574166
Previously, we and others have shown that RhoA and ROCK signaling are required for negatively regulating integrin-mediated adhesion and for tail retraction of migrating leukocytes. This study continues our investigation into the molecular mechanisms underlying RhoA/ROCK-regulated integrin adhesion. We show that inhibition of ROCK up-regulates integrin-mediated adhesion, which is accompanied ... More
A Rac switch regulates random versus directionally persistent cell migration.
AuthorsPankov R, Endo Y, Even-Ram S, Araki M, Clark K, Cukierman E, Matsumoto K, Yamada KM
JournalJ Cell Biol
PubMed ID16129786
Directional migration moves cells rapidly between points, whereas random migration allows cells to explore their local environments. We describe a Rac1 mechanism for determining whether cell patterns of migration are intrinsically random or directionally persistent. Rac activity promoted the formation of peripheral lamellae that mediated random migration. Decreasing Rac activity ... More
Inducible dimerization of FGFR1: development of a mouse model to analyze progressive transformation of the mammary gland.
AuthorsWelm BE, Freeman KW, Chen M, Contreras A, Spencer DM, Rosen JM
JournalJ Cell Biol
PubMed ID12011115
To develop an inducible and progressive model of mammary gland tumorigenesis, transgenic mice were generated with a mouse mammary tumor virus-long terminal repeat-driven, conditional, fibroblast growth factor (FGF)-independent FGF receptor (FGFR)1 (iFGFR1) that can be induced to dimerize with the drug AP20187. Treatment of transgenic mice with AP20187 resulted in ... More
Evidence that stem cells reside in the adult Drosophila midgut epithelium.
AuthorsMicchelli CA, Perrimon N
JournalNature
PubMed ID16340959
Adult stem cells maintain organ systems throughout the course of life and facilitate repair after injury or disease. A fundamental property of stem and progenitor cell division is the capacity to retain a proliferative state or generate differentiated daughter cells; however, little is currently known about signals that regulate the ... More
Immobilization of bioactive fibroblast growth factor-2 into cubic proteinous microcrystals (Bombyx mori cypovirus polyhedra) that are insoluble in a physiological cellular environment.
AuthorsMori H, Shukunami C, Furuyama A, Notsu H, Nishizaki Y, Hiraki Y
JournalJ Biol Chem
PubMed ID17430896
The supramolecular architecture of the extracellular matrix and the disposition of its specific accessory molecules give rise to variable heterotopic signaling cues for single cells. Here we have described the successful occlusion of human fibroblast growth factor-2 (FGF-2) into the cubic inclusion bodies (FGF-2 polyhedra) of the Bombyx mori cytoplasmic ... More
Recruitment of the Arp2/3 complex to vinculin: coupling membrane protrusion to matrix adhesion.
AuthorsDeMali KA, Barlow CA, Burridge K
JournalJ Cell Biol
PubMed ID12473693
Cell migration involves many steps, including membrane protrusion and the development of new adhesions. Here we have investigated whether there is a link between actin polymerization and integrin engagement. In response to signals that trigger membrane protrusion, the actin-related protein (Arp)2/3 complex transiently binds to vinculin, an integrin-associated protein. The ... More
AuthorsKultti A, Rilla K, Tiihonen R, Spicer AP, Tammi RH, Tammi MI
JournalJ Biol Chem
PubMed ID16595683
Hyaluronan synthases (HASs) are plasma membrane enzymes that simultaneously elongate, bind, and extrude the growing hyaluronan chain directly into extracellular space. In cells transfected with green fluorescent protein (GFP)-tagged Has3, the dorsal surface was decorated by up to 150 slender, 3-20-microm-long microvillus-type plasma membrane protrusions, which also contained filamentous actin, ... More
RhoA is required for cortical retraction and rigidity during mitotic cell rounding.
AuthorsMaddox AS, Burridge K
JournalJ Cell Biol
PubMed ID12538643
Mitotic cell rounding is the process of cell shape change in which a flat interphase cell becomes spherical at the onset of mitosis. Rearrangement of the actin cytoskeleton, de-adhesion, and an increase in cortical rigidity accompany mitotic cell rounding. The molecular mechanisms that contribute to this process have not been ... More
Two pathways converge at CED-10 to mediate actin rearrangement and corpse removal in C. elegans.
AuthorsKinchen JM, Cabello J, Klingele D, Wong K, Feichtinger R, Schnabel H, Schnabel R, Hengartner MO
JournalNature
PubMed ID15744306
The removal of apoptotic cells is essential for the physiological well being of the organism. In Caenorhabditis elegans, two conserved, partially redundant genetic pathways regulate this process. In the first pathway, the proteins CED-2, CED-5 and CED-12 (mammalian homologues CrkII, Dock180 and ELMO, respectively) function to activate CED-10 (Rac1). In ... More
The mammalian Scribble polarity protein regulates epithelial cell adhesion and migration through E-cadherin.
AuthorsQin Y, Capaldo C, Gumbiner BM, Macara IG
JournalJ Cell Biol
PubMed ID16344308
Scribble (Scrib) is a conserved polarity protein required in Drosophila melanogaster for synaptic function, neuroblast differentiation, and epithelial polarization. It is also a tumor suppressor. In rodents, Scrib has been implicated in receptor recycling and planar polarity but not in apical/basal polarity. We now show that knockdown of Scrib disrupts ... More
Control of axon elongation via an SDF-1alpha/Rho/mDia pathway in cultured cerebellar granule neurons.
AuthorsArakawa Y, Bito H, Furuyashiki T, Tsuji T, Takemoto-Kimura S, Kimura K, Nozaki K, Hashimoto N, Narumiya S
JournalJ Cell Biol
PubMed ID12707308
Rho-GTPase has been implicated in axon outgrowth. However, not all of the critical steps controlled by Rho have been well characterized. Using cultured cerebellar granule neurons, we show here that stromal cell-derived factor (SDF)-1alpha, a neural chemokine, is a physiological ligand that can turn on two distinct Rho-dependent pathways with ... More
Phosphatidylinositol-3,4,5-trisphosphate regulates the formation of the basolateral plasma membrane in epithelial cells.
AuthorsGassama-Diagne A, Yu W, ter Beest M, Martin-Belmonte F, Kierbel A, Engel J, Mostov K
JournalNat Cell Biol
PubMed ID16921364
Polarity is a central feature of eukaryotic cells and phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3) has a central role in the polarization of neurons and chemotaxing cells. In polarized epithelial cells, PtdIns(3,4,5)P3 is stably localized at the basolateral plasma membrane, but excluded from the apical plasma membrane, as shown by localization of GFP ... More
A role for actin, Cdc1p, and Myo2p in the inheritance of late Golgi elements in Saccharomyces cerevisiae.
In Saccharomyces cerevisiae, Golgi elements are present in the bud very early in the cell cycle. We have analyzed this Golgi inheritance process using fluorescence microscopy and genetics. In rapidly growing cells, late Golgi elements show an actin-dependent concentration at sites of polarized growth. Late Golgi elements are apparently transported ... More
The Rab5 activator ALS2/alsin acts as a novel Rac1 effector through Rac1-activated endocytosis.
AuthorsKunita R, Otomo A, Mizumura H, Suzuki-Utsunomiya K, Hadano S, Ikeda JE
JournalJ Biol Chem
PubMed ID17409386
Mutations in the ALS2 gene cause a number of recessive motor neuron diseases, indicating that the ALS2 protein (ALS2/alsin) is vital for motor neurons. ALS2 acts as a guanine nucleotide exchange factor (GEF) for Rab5 (Rab5GEF) and is involved in endosome dynamics. However, the spatiotemporal regulation of the ALS2-mediated Rab5 ... More
Membrane-type 1 matrix metalloproteinase cleaves CD44 and promotes cell migration.
AuthorsKajita M, Itoh Y, Chiba T, Mori H, Okada A, Kinoh H, Seiki M
JournalJ Cell Biol
PubMed ID11381077
Migratory cells including invasive tumor cells frequently express CD44, a major receptor for hyaluronan and membrane-type 1 matrix metalloproteinase (MT1-MMP) that degrades extracellular matrix at the pericellular region. In this study, we demonstrate that MT1-MMP acts as a processing enzyme for CD44H, releasing it into the medium as a soluble ... More
Two distinct distributions of F-actin are present in the hyphal apex of the oomycete Achlya bisexualis.
AuthorsYu YP, Jackson SL, Garrill A
JournalPlant Cell Physiol
PubMed ID15047875
We show that two distinct distributions of F-actin are present in the hyphal apex of the oomycete Achlya bisexualis, that have been chemically fixed with a combination of methylglyoxal and formaldehyde and stained with Alexa phalloidin. In approximately one half of the hyphae examined, an F-actin depleted zone within the ... More
Differential requirement of G alpha12, G alpha13, G alphaq, and G beta gamma for endothelin-1-induced c-Jun NH2-terminal kinase and extracellular signal-regulated kinase activation.
AuthorsArai K, Maruyama Y, Nishida M, Tanabe S, Takagahara S, Kozasa T, Mori Y, Nagao T, Kurose H
JournalMol Pharmacol
PubMed ID12606754
In the present study, we examined the roles of G(12), G(13), G(q), and G(i) in endothelin-1-induced hypertrophic responses. Endothelin-1 stimulation activated extracellular signal-regulated kinase (ERK) and c-Jun NH(2)-terminal kinase (JNK) in cultured rat neonatal myocytes. The activation of JNK, but not ERK, was inhibited by the expression of carboxyl terminal ... More
Filopodia and actin arcs guide the assembly and transport of two populations of microtubules with unique dynamic parameters in neuronal growth cones.
AuthorsSchaefer AW, Kabir N, Forscher P
JournalJ Cell Biol
PubMed ID12105186
We have used multimode fluorescent speckle microscopy (FSM) and correlative differential interference contrast imaging to investigate the actin-microtubule (MT) interactions and polymer dynamics known to play a fundamental role in growth cone guidance. We report that MTs explore the peripheral domain (P-domain), exhibiting classical properties of dynamic instability. MT extension ... More
The role of LIP5 and CHMP5 in multivesicular body formation and HIV-1 budding in mammalian cells.
AuthorsWard DM, Vaughn MB, Shiflett SL, White PL, Pollock AL, Hill J, Schnegelberger R, Sundquist WI, Kaplan J
JournalJ Biol Chem
PubMed ID15644320
We examined the function of LIP5 in mammalian cells, because the yeast homologue Vta1p was recently identified as a protein required for multivesicular body (MVB) formation. LIP5 is predominantly a cytosolic protein. Depletion of LIP5 by small inhibitory RNA (siRNA) does not affect the distribution or morphology of early endosomes, ... More
Phosphatidylinositol 4,5-biphosphate (PIP2)-induced vesicle movement depends on N-WASP and involves Nck, WIP, and Grb2.
AuthorsBenesch S, Lommel S, Steffen A, Stradal TE, Scaplehorn N, Way M, Wehland J, Rottner K
JournalJ Biol Chem
PubMed ID12147689
Wiskott-Aldrich syndrome protein (WASP)/Scar family proteins promote actin polymerization by stimulating the actin-nucleating activity of the Arp2/3 complex. While Scar/WAVE proteins are thought to be involved in lamellipodia protrusion, the hematopoietic WASP has been implicated in various actin-based processes such as chemotaxis, podosome formation, and phagocytosis. Here we show that ... More
Mutants affecting the structure of the cortical endoplasmic reticulum in Saccharomyces cerevisiae.
AuthorsPrinz WA, Grzyb L, Veenhuis M, Kahana JA, Silver PA, Rapoport TA
JournalJ Cell Biol
PubMed ID10931860
We find that the peripheral ER in Saccharomyces cerevisiae forms a dynamic network of interconnecting membrane tubules throughout the cell cycle, similar to the ER in higher eukaryotes. Maintenance of this network does not require microtubule or actin filaments, but its dynamic behavior is largely dependent on the actin cytoskeleton. ... More
Membrane raft association of CD47 is necessary for actin polymerization and protein kinase C theta translocation in its synergistic activation of T cells.
AuthorsRebres RA, Green JM, Reinhold MI, Ticchioni M, Brown EJ
JournalJ Biol Chem
PubMed ID11114301
CD47 is a ubiquitously expressed membrane protein with an extracellular Ig domain and a multiple membrane-spanning domain that can synergize with antigen to induce interleukin (IL)-2 secretion by T lymphocytes. Ligation of CD47 induced actin polymerization and increased protein kinase Ctheta (PKCtheta) association with the cytoskeleton independent of antigen receptor ... More
Fluid shear stress induces less calcium response in a single primary osteocyte than in a single osteoblast: implication of different focal adhesion formation.
AuthorsKamioka H, Sugawara Y, Murshid SA, Ishihara Y, Honjo T, Takano-Yamamoto T
JournalJ Bone Miner Res
PubMed ID16813522
The immediate calcium response to fluid shear stress was compared between osteocytes and osteoblasts on glass using real-time calcium imaging. The osteoblasts were responsive to fluid shear stress of up to 2.4 Pa, whereas the osteocytes were not. The difference in flow-induced calcium may be related to differences in focal ... More
Deficiency of Src homology 2-containing phosphatase 1 results in abnormalities in murine neutrophil function: studies in motheaten mice.
AuthorsKruger J, Butler JR, Cherapanov V, Dong Q, Ginzberg H, Govindarajan A, Grinstein S, Siminovitch KA, Downey GP
JournalJ Immunol
PubMed ID11067945
Neutrophils, an essential component of the innate immune system, are regulated in part by signaling pathways involving protein tyrosine phosphorylation. While protein tyrosine kinase functions in regulating neutrophil behavior have been extensively investigated, little is known about the role for specific protein tyrosine phosphatases (PTP) in modulating neutrophil signaling cascades. ... More
Role of actin-filament disassembly in lamellipodium protrusion in motile cells revealed using the drug jasplakinolide.
AuthorsCramer LP
JournalCurr Biol
PubMed ID10531004
BACKGROUND: In motile cells, protrusion of the lamellipodium (a type of cell margin) requires assembly of actin monomers into actin filaments at the tip of the lamellipodium. The importance of actin-filament disassembly in this process is less well understood, and is assessed here using the actin drug jasplakinolide, which has ... More
Calcium-mediated transductive systems and functionally active gap junctions in astrocyte-like GL15 cells.
AuthorsMariggio MA, Mazzoleni G, Pietrangelo T, Guarnieri S, Morabito C, Steimberg N, Fano G
JournalBMC Physiol
PubMed ID11384510
BACKGROUND: It has been proposed that GL15, a human cell line derived from glioblastoma multiforme, is a possible astroglial-like cell model, based on the presence of cytoplasmic glial fibrillary acidic protein. RESULTS: The aim of this work was to delineate the functional characteristics of GL15 cells using various experimental approaches, ... More
The type III intermediate filament vimentin regulates organelle distribution and modulates autophagy.
AuthorsBiskou O, Casanova V, Hooper KM, Kemp S, Wright GP, Satsangi J, Barlow PG, Stevens C
JournalPLoS One
PubMed ID30699149
'The cytoskeletal protein vimentin plays a key role in positioning of organelles within the cytosol and has been linked to the regulation of numerous cellular processes including autophagy, however, how vimentin regulates autophagy remains relatively unexplored. Here we report that inhibition of vimentin using the steroidal lactone Withaferin A (WFA) ... More
Multi-directional cellular alignment in 3D guided by electrohydrodynamically-printed microlattices.
AuthorsMao M, He J, Li Z, Han K, Li D
JournalActa Biomater
PubMed ID31669696
'Recapitulating aligned cellular architectures of native tissues in vitro is important to engineer artificial tissue analogs with desired biological functions. Here a novel strategy is presented to direct three-dimensional (3D) cellular alignment by embedding cell/collagen hydrogel into the predefined electrohydrodynamically-printed microlattices. The cell/collagen hydrogel, originally filled within the printed microlattices ... More
Inhibition of thyroid hormone signaling protects retinal pigment epithelium and photoreceptors from cell death in a mouse model of age-related macular degeneration.
AuthorsMa H, Yang F, Ding XQ
JournalCell Death Dis
PubMed ID31932580
'Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Dry AMD is characterized by a progressive macular degeneration of the retinal pigment epithelium (RPE) and photoreceptors, and the RPE oxidative damage/dystrophy is at the core of the disease. Recent population/patients-based studies have shown an association of ... More
Tunable Expression Tools Enable Single-Cell Strain Distinction in the Gut Microbiome.
Authors
JournalCell
PubMed ID28431251
Spatially restricted Hedgehog signalling regulates HGF-induced branching of the adult prostate.
Authors
JournalNat Cell Biol
PubMed ID25362352
Prpf31 is essential for the survival and differentiation of retinal progenitor cells by modulating alternative splicing.
Authors
JournalNucleic Acids Res
PubMed ID33476374
Proteome labeling and protein identification in specific tissues and at specific developmental stages in an animal.
Authors
JournalNat Biotechnol
PubMed ID24727715
Regulation of Collective Metastasis by Nanolumenal Signaling.
Authors
JournalCell
PubMed ID33007268
Directed migration of cancer cells guided by the graded texture of the underlying matrix.
Authors
JournalNat Mater
PubMed ID26974411
All-Inkjet-Printed 3D Alveolar Barrier Model with Physiologically Relevant Microarchitecture.
Authors
JournalAdv Sci (Weinh)
PubMed ID34026463
Transcription upregulation via force-induced direct stretching of chromatin.
Authors
JournalNat Mater
PubMed ID27548707
An early cell shape transition drives evolutionary expansion of the human forebrain.
Authors
JournalCell
PubMed ID33765444
Cytotoxic lymphocytes target characteristic biophysical vulnerabilities in cancer.
Authors
JournalImmunity
PubMed ID33756102
Assessment of the Angiogenic Potential of 2-Deoxy-D-Ribose Using a Novel
AuthorsDikici S, Aldemir Dikici B, Bhaloo SI, Balcells M, Edelman ER, MacNeil S, Reilly GC, Sherborne C, Claeyssens F
JournalFront Bioeng Biotechnol
PubMed ID32010677
Angiogenesis is a highly ordered physiological process regulated by the interaction of endothelial cells with an extensive variety of growth factors, extracellular matrix components and mechanical stimuli. One of the most important challenges in tissue engineering is the rapid neovascularization of constructs to ensure their survival after transplantation. To achieve ... More
Tks5 SH3 domains exhibit differential effects on invadopodia development.
AuthorsDaly C, Logan B, Breeyear J, Whitaker K, Ahmed M, Seals DF
JournalPLoS One
PubMed ID31999741
The Src substrate Tks5 helps scaffold matrix-remodeling invadopodia in invasive cancer cells. Focus was directed here on how the five SH3 domains of Tks5 impact that activity. Mutations designed to inhibit protein-protein interactions were created in the individual SH3 domains of Tks5, and the constructs were introduced into the LNCaP ... More