9,205 results match your criteria Molecular biology of the cell[Journal]


REEP3 and REEP4 determine the tubular morphology of the endoplasmic reticulum during mitosis.

Mol Biol Cell 2019 Apr 17:mbcE18110698. Epub 2019 Apr 17.

Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany.

The endoplasmic reticulum (ER) is extensively remodeled during metazoan open mitosis. However, whether the ER becomes more tubular or more cisternal during mitosis is controversial, and dedicated factors governing the morphology of the mitotic ER have remained elusive. Here, we describe the ER membrane proteins REEP3 and REEP4 as major determinants of ER morphology in metaphase cells. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E18-11-0698
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http://dx.doi.org/10.1091/mbc.E18-11-0698DOI Listing
April 2019
6 Reads

Non-muscle myosin IIA and IIB differentially modulate migration and alter gene expression in primary mouse tumorigenic cells.

Mol Biol Cell 2019 Apr 17:mbcE18120790. Epub 2019 Apr 17.

School of Biological Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.

Though many cancers are known to show upregulation of Nonmuscle myosin (NM) IIA and -IIB, the mechanism by which NMIIs aid in cancer development remains unexplored. Here we demonstrate that tumor-generating, fibroblast-like cells isolated from 3-methylcholanthrene (3MC)-induced murine tumor exhibit distinct phospho-dependent localization of NMIIA and NMIIB at the perinuclear area and tip of the filopodia and affect cell migration differentially. While NMIIA-KD affects protrusion dynamics and increases cell directionality, NMIIB-KD lowers migration speed and increases filopodial branching. Read More

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http://dx.doi.org/10.1091/mbc.E18-12-0790DOI Listing

Rudhira/BCAS3 couples microtubules and intermediate filaments to promote cell migration for angiogenic remodeling.

Mol Biol Cell 2019 Apr 17:mbcE18080484. Epub 2019 Apr 17.

Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.

Blood vessel formation requires endothelial cell (EC) migration that depends on dynamic remodeling of the cytoskeleton. Rudhira/Breast Carcinoma Amplified Sequence 3 (BCAS3) is a cytoskeletal protein essential for EC migration and sprouting angiogenesis during mouse development and implicated in metastatic disease. Here, we report that Rudhira mediates cytoskeleton organization and dynamics during EC migration. Read More

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http://dx.doi.org/10.1091/mbc.E18-08-0484DOI Listing

Role of KASH domain lengths in the regulation of LINC complexes.

Mol Biol Cell 2019 Apr 17:mbcE19020079. Epub 2019 Apr 17.

Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, United States.

The LINC complex is formed by the conserved interactions between SUN and KASH domain proteins, providing a physical coupling between the nucleoskeleton and cytoskeleton that mediates the transfer of physical forces across the nuclear envelope. The LINC complex can perform distinct cellular functions by pairing various KASH domain proteins with the same SUN domain protein. For example, In , SUN protein UNC-84 binds to two KASH proteins UNC-83 and ANC-1 to mediate nuclear migration and anchorage, respectively. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E19-02-0079
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http://dx.doi.org/10.1091/mbc.E19-02-0079DOI Listing
April 2019
1 Read

Structure and function of Spc42 coiled-coils in yeast centrosome assembly and duplication.

Mol Biol Cell 2019 Apr 10:mbcE19030167. Epub 2019 Apr 10.

Department of Biochemistry, University of Wisconsin-Madison, WI 53706 USA.

Centrosomes and spindle pole bodies (SPBs) are membraneless organelles whose duplication and assembly is necessary for bipolar mitotic spindle formation. The structural organization and functional roles of major proteins in these organelles can provide critical insights into cell division control. Spc42, a phosphoregulated protein with an N-terminal dimeric coiled-coil, assembles into a hexameric array at the budding yeast SPB core, where it functions as a scaffold for SPB assembly. Read More

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http://dx.doi.org/10.1091/mbc.E19-03-0167DOI Listing

N-glycosylation-dependent regulation of hK17.1 currents.

Mol Biol Cell 2019 Apr 10:mbcE18100687. Epub 2019 Apr 10.

Department of Cardiology, University of Heidelberg, Heidelberg, Germany.

Two-pore-domain potassium (K) channels mediate potassium background currents that stabilize the resting membrane potential and facilitate action potential repolarization. In the human heart, hK17.1 channels are predominantly expressed in the atria and Purkinje cell. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0687DOI Listing
April 2019
1 Read

Microtubule Polymerase and Processive Plus-end Tracking functions originate from distinct features within TOG domain arrays.

Mol Biol Cell 2019 Apr 10:mbcE19020093. Epub 2019 Apr 10.

Molecular Cellular Biology Department, University of California, Davis, CA.

XMAP215/Stu2/Alp14 accelerates tubulin polymerization while processively tracking microtubule plus-ends via Tumor Overexpressed Gene (TOG) domain arrays. It remains poorly understood how these functions arise from tubulin recruitment, mediated by the distinct TOG1 and TOG2 domains, or the assembly of these arrays into large square complexes. Here, we describe a relationship between microtubule plus-end tracking and polymerase functions revealing their distinct origin within TOG arrays. Read More

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http://dx.doi.org/10.1091/mbc.E19-02-0093DOI Listing

Arf6, JIP3 and Dynein shape and mediate Macropinocytosis.

Mol Biol Cell 2019 Apr 10:mbcE19010022. Epub 2019 Apr 10.

Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892.

Macropinocytosis is an actin-driven form of clathrin-independent endocytosis that generates an enlarged structure, the macropinosome. Although many studies focus on signaling molecules and phosphoinositides involved in initiating macropinocytosis, the commitment to forming a macropinosome and the handling of that membrane has not been studied in detail. Here we show in HT1080 cells, a human fibrosarcoma cell line, a requirement for microtubules, dynein, the JIP3 microtubule motor scaffold protein, and Arf6, a JIP3 interacting protein, for the formation and inward movement of the macropinosome. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E19-01-0022
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http://dx.doi.org/10.1091/mbc.E19-01-0022DOI Listing
April 2019
7 Reads

Analysis of the roles of phosphatidylinositol-4,5- bisphosphate and individual subunits in assembly, localization and function of Saccharomyces cerevisiae Target of Rapamycin Complex 2.

Mol Biol Cell 2019 04 10:mbcE18100682. Epub 2019 Apr 10.

Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley, California 94720 USA.

Eukaryotic cell survival requires maintenance of plasma membrane (PM) homeostasis in response to environmental insults and changes in lipid metabolism. In yeast, a key regulator of PM homeostasis is Target of Rapamycin (TOR) complex 2 (TORC2), a multi-protein complex containing the evolutionarily conserved TOR protein kinase isoform Tor2. PM localization is essential for TORC2 function. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0682DOI Listing
April 2019
1 Read

Synthetic and genetic dimers as quantification ruler for single-molecule counting with PALM.

Mol Biol Cell 2019 Apr 10:mbcE18100661. Epub 2019 Apr 10.

Single Molecule Biophysics, Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue Str. 7, 60438 Frankfurt, Germany.

How membrane proteins oligomerize determines their function. Super-resolution microscopy can report on protein clustering and extract quantitative molecular information. Here, we evaluate the blinking kinetics of four photoactivatable fluorescent proteins for quantitative single-molecule microscopy. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E18-10-0661
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http://dx.doi.org/10.1091/mbc.E18-10-0661DOI Listing
April 2019
5 Reads

Insulin-responsive amino peptidase follows the "glut4 pathway" but is dispensable for the formation and translocation of insulin-responsive vesicles.

Mol Biol Cell 2019 Apr 3:mbcE18120792. Epub 2019 Apr 3.

Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118.

In fat and skeletal muscle cells, insulin-responsive amino peptidase, IRAP, along with Glut4 and sortilin, represents a major component protein of the insulin responsive vesicles, IRVs. Here, we are showing that IRAP, similar to Glut4 and sortilin, is retrieved from endosomes to TGN by retromer. Unlike Glut4, retrograde transport of IRAP does not require sortilin, as retromer can directly bind to the cytoplasmic tail of IRAP. Read More

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http://dx.doi.org/10.1091/mbc.E18-12-0792DOI Listing

The desmosome is a mesoscale lipid raft-like membrane domain.

Mol Biol Cell 2019 Apr 3:mbcE18100649. Epub 2019 Apr 3.

Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA.

Desmogleins are cadherin family adhesion molecules essential for epidermal integrity. Previous studies have shown that desmogleins associate with lipid rafts, but the significance of this association was not clear. Here, we report that the desmoglein transmembrane domain (TMD) is the primary determinant of raft association. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0649DOI Listing

Newly synthesized claudins but not occludin are added to the basal side of the tight junction.

Mol Biol Cell 2019 Apr 3:mbcE19010008. Epub 2019 Apr 3.

Laboratory of Tight Junction Structure and Function, National Institutes of Health, Building 50, Room 4525, 50 South Drive, Bethesda, MD 20892, USA.

A network of claudin strands creates continuous cell-cell contacts to form the intercellular tight junction barrier; a second protein, occludin, is associated along these strands. The physiological barrier remains stable despite protein turnover, which involves removal and replacement of claudins both at steady state and during junction remodeling. Here we use a pulse-block-pulse labeling protocol with fluorescent ligands to label SNAP/CLIP-tags fused to claudins and occludin to identify their spatial trafficking pathways and kinetics in MDCK monolayers. Read More

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http://dx.doi.org/10.1091/mbc.E19-01-0008DOI Listing

Promiscuity of the catalytic Sec7 domain within the guanine nucleotide exchange factor GBF1 in ARF activation, Golgi homeostasis, and effector recruitment.

Mol Biol Cell 2019 Apr 3:mbcE18110711. Epub 2019 Apr 3.

Department of Cell, Developmental and Integrative Biology; and.

The integrity of the Golgi and trans-Golgi network (TGN) is disrupted by Brefeldin A, which inhibits the GBF1, BIG1 and BIG2 guanine nucleotide exchange factors (GEFs). Using a cellular replacement assay to assess GBF1 functionality without interference from the BIGs, we show that GBF1 alone maintains Golgi architecture, facilitates secretion, activates ARF1, 3, 4 and 5, and recruits ARF effectors to Golgi membranes. Unexpectedly, GBF1 also supports TGN integrity and recruits numerous TGN-localized ARF effectors. Read More

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http://dx.doi.org/10.1091/mbc.E18-11-0711DOI Listing

Long-range, through-lattice coupling improves predictions of microtubule catastrophe.

Authors:
Tae Kim Luke M Rice

Mol Biol Cell 2019 Apr 3:mbcE18100641. Epub 2019 Apr 3.

UT Southwestern Medical Center, Departments of Biophysics and Biochemistry, 5323 Harry Hines Blvd, Dallas, TX 75390.

Microtubules are cylindrical polymers of αβ-tubulin that play critical roles in fundamental processes like chromosome segregation and vesicular transport. Microtubules display dynamic instability, switching stochastically between growing and rapid shrinking as a consequence of GTPase activity in the lattice. The molecular mechanisms behind microtubule catastrophe, the switch from growing to rapid shrinking, remain poorly defined. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0641DOI Listing

Yb body assembly on the flamenco piRNA precursor transcripts reduces genic piRNA production.

Mol Biol Cell 2019 Apr 3:mbcE17100591. Epub 2019 Apr 3.

Department of Molecular Genetics of Cell, Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, 123182, Moscow, Russia.

In Drosophila ovarian somatic cells, piRNAs against transposable elements are mainly produced from the ∼180-kb flamenco ( flam) locus. flam transcripts are gathered into foci, located close to the nuclear envelope, and processed into piRNAs in the cytoplasmic Yb bodies. The mechanism of Yb body formation remains unknown. Read More

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http://dx.doi.org/10.1091/mbc.E17-10-0591DOI Listing

Mitochondrial carrier protein overloading and misfolding induce aggresomes and proteostatic adaptations in the cytosol.

Mol Biol Cell 2019 Mar 20:mbcE19010046. Epub 2019 Mar 20.

Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, Syracuse, New York 13210, USA.

Studies in yeast showed that mitochondrial stressors not directly targeting the protein import machinery can cause mitochondrial Precursor Overaccumulation Stress (mPOS) in the cytosol independent of bioenergetics. Here, we demonstrate mPOS and stress responses in human cells. We show that overloading of mitochondrial membrane carriers, but not matrix proteins, is sufficient to induce cytosolic aggresomes and apoptosis. Read More

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http://dx.doi.org/10.1091/mbc.E19-01-0046DOI Listing
March 2019
1 Read

IRSp53 coordinates AMPK and 14-3-3 signaling to regulate filopodia dynamics and directed cell migration.

Mol Biol Cell 2019 03 20:mbcE18090600. Epub 2019 Mar 20.

Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.

Filopodia are actin-filled membrane protrusions that play essential roles in cell motility, cell-cell communication, and act as precursors of dendritic spines. IRSp53 is an essential regulator of filopodia formation, which couples Rho-GTPase signaling to actin cytoskeleton and membrane remodeling. IRSp53 has three major domains: an N-terminal inverse-BAR (I-BAR) domain, a Cdc42- and SH3-binding CRIB-PR domain, and an SH3 domain that binds downstream cytoskeletal effectors. Read More

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http://dx.doi.org/10.1091/mbc.E18-09-0600DOI Listing

Hic-5 regulates Src-induced invadopodia rosette formation and organization.

Mol Biol Cell 2019 Mar 20:mbcE18100629. Epub 2019 Mar 20.

Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA.

Fibroblasts transformed by the proto-oncogene Src form individual invadopodia that can spontaneously self-organize into large matrix-degrading super-structures called rosettes. However, the mechanisms by which the invadopodia can spatio-temporally reorganize their architecture is not well understood. Herein, we show that Hic-5, a close relative of the scaffold protein paxillin, is essential for the formation and organization of rosettes in active Src-transfected NIH3T3 fibroblasts and cancer-associated fibroblasts. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0629DOI Listing

A specialized condensin complex participates in somatic nuclear maturation in Tetrahymena thermophila.

Mol Biol Cell 2019 Mar 20:mbcE18080487. Epub 2019 Mar 20.

Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria.

Condensins are highly conserved proteins that are important for chromosome maintenance in nearly all forms of life. While many organisms employ two forms of the condensin complex, the condensin genes in Tetrahymena have expanded even further. Here we report a form of condensin that is specifically active during sexual reproduction. Read More

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http://dx.doi.org/10.1091/mbc.E18-08-0487DOI Listing

Drosophila p53 directs non-apoptotic programs in postmitotic tissue.

Mol Biol Cell 2019 Mar 20:mbcE18120791. Epub 2019 Mar 20.

Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.

TP53 is the most frequently mutated gene in human cancers, and despite intensive research efforts, genome-scale studies of p53 function in whole animal models are rare. The need for such in vivo studies is underscored by recent challenges to established paradigms, indicating that unappreciated p53 functions contribute to cancer prevention. Here we leveraged the Drosophila system to interrogate p53 function in a postmitotic context. Read More

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http://dx.doi.org/10.1091/mbc.E18-12-0791DOI Listing

In vitro BioID: Mapping the CENP-A Micro-Environment with high temporal and spatial resolution.

Mol Biol Cell 2019 Mar 20:mbcE18120799. Epub 2019 Mar 20.

Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, UK.

The centromere is located at the primary constriction of condensed chromosomes where it acts as a platform regulating chromosome segregation. The histone H3 variant CENP-A is the foundation for kinetochore formation. CENP-A directs formation of a highly dynamic molecular neighbourhood whose temporal characterisation during mitosis remains a challenge due to limitations in available techniques. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E18-12-0799
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March 2019
1 Read

Spindle mechanics and chromosome segregation.

Mol Biol Cell 2019 Mar;30(6):735-736

IMBA-Institute of Molecular Biotechnology of the Austrian Academy of Sciences, 1030 Vienna, Austria.

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http://dx.doi.org/10.1091/mbc.E19-01-0037DOI Listing

The role of metabolism in cellular processes.

Mol Biol Cell 2019 Mar;30(6):733

Department of Pharmacology, University of Washington, Seattle, WA 98195.

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http://dx.doi.org/10.1091/mbc.E19-01-0004DOI Listing

Organelle zones.

Mol Biol Cell 2019 Mar;30(6):731

Max-Planck Institute for Biochemistry, 82152 Martinsried, Germany.

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http://dx.doi.org/10.1091/mbc.E18-12-0818DOI Listing
March 2019
1 Read

Cell cycle, cell division, cell death.

Mol Biol Cell 2019 Mar;30(6):732

Department of Biology, Stanford University, Stanford, CA 94305.

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http://dx.doi.org/10.1091/mbc.E18-12-0819DOI Listing
March 2019
1 Read

Desiccation tolerance: an unusual window into stress biology.

Mol Biol Cell 2019 Mar;30(6):737-741

Biology Program, California State University-Channel Islands, Camarillo, CA 93012.

Climate change has accentuated the importance of understanding how organisms respond to stresses imposed by changes to their environment, like water availability. Unusual organisms, called anhydrobiotes, can survive loss of almost all intracellular water. Desiccation tolerance of anhydrobiotes provides an unusual window to study the stresses and stress response imposed by water loss. Read More

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http://dx.doi.org/10.1091/mbc.E17-04-0257DOI Listing

Motors in transport and cytoskeleton remodeling.

Mol Biol Cell 2019 Mar;30(6):734

Pennsylvania Muscle Institute and Department of Physiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia PA 19104.

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http://dx.doi.org/10.1091/mbc.E19-01-0011DOI Listing

Correction.

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Mol Biol Cell 2019 Mar;30(6):808-809

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http://dx.doi.org/10.1091/mbc.E17-11-0648-corrDOI Listing

Integrin α6β4E variant is associated with actin and CD9 structures and modifies the biophysical properties of cell-cell and cell-extracellular matrix interactions.

Mol Biol Cell 2019 Mar 13;30(7):838-850. Epub 2019 Mar 13.

Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ 85724.

Integrin α6β4 is an essential, dynamic adhesion receptor for laminin 332 found on epithelial cells, required for formation of strong cell-extracellular matrix (ECM) adhesion and induced migration, and coordinated by regions of the β4C cytoplasmic domain. β4E, a unique splice variant of β4 expressed in normal tissue, contains a cytoplasmic domain of 231 amino acids with a unique sequence of 114 amino acids instead of β4C's canonical 1089 amino acids. We determined the distribution of α6β4E within normal human glandular epithelium and its regulation and effect on cellular biophysical properties. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0652DOI Listing
March 2019
1 Read

Stretching magnitude-dependent inactivation of AKT by ROS led to enhanced p53 mitochondrial translocation and myoblasts apoptosis.

Mol Biol Cell 2019 Mar 13:mbcE18120770. Epub 2019 Mar 13.

Department of stomatology medical center, Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China.

Previously, we had shown that high magnitude stretch (HMS), rather than low magnitude stretch (LMS), induced significant apoptosis of skeletal muslce C2C12 myoblasts. However, the molecular mechanism remains obscure. In this study, we found that p53 protein accumulated in nucleus of LMS-loaded cells, while it translocated into mitochondria of HMS-loaded cells. Read More

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http://dx.doi.org/10.1091/mbc.E18-12-0770DOI Listing
March 2019
4.466 Impact Factor

Myosin II governs intracellular pressure and traction by distinct tropomyosin-dependent mechanisms.

Mol Biol Cell 2019 Mar 13:mbcE18060355. Epub 2019 Mar 13.

Department of Biology, Drexel University, Philadelphia, PA.

Two-dimensional (2D) substrate rigidity promotes myosin II activity to increase traction force in a process negatively regulated by tropomyosin (Tpm) 2.1. We recently discovered that actomyosin contractility can increase intracellular pressure and switch tumor cells from low-pressure lamellipodia to high-pressure lobopodial protrusions during 3D migration. Read More

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http://dx.doi.org/10.1091/mbc.E18-06-0355DOI Listing

ELMOD2 regulates mitochondrial fusion in a mitofusin-dependent manner, downstream of ARL2.

Mol Biol Cell 2019 Mar 13:mbcE18120804. Epub 2019 Mar 13.

Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA 30322.

Mitochondria are essential and dynamic organelles, undergoing constant fission and fusion. The primary players in mitochondrial morphology (MFN1/2, OPA1, DRP1) have been identified, but their mechanism(s) of regulation are still being elucidated. ARL2 is a regulatory GTPase which has previously been shown to play a role in the regulation of mitochondrial morphology. Read More

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March 2019
2 Reads

TgCep250 is dynamically processed through the division cycle and essential for structural integrity of the Toxoplasma centrosome.

Mol Biol Cell 2019 Mar 13:mbcE18100608. Epub 2019 Mar 13.

Department of Biology, Boston College, Chestnut Hill, MA 02467.

The apicomplexan centrosome has a unique bipartite structure comprising an inner- and outer-core responsible for the nuclear cycle (mitosis) and budding cycles (cytokinesis), respectively. Although these two cores are always associated, they function independently to facilitate polyploid intermediates in the production of many progeny per replication round. Here, we describe the function of a large coiled-coil protein in Toxoplasma gondii, TgCep250, in connecting the two centrosomal cores and promoting their structural integrity. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0608DOI Listing

PP2A-B55/SUR-6 collaborates with the nuclear lamina for centrosome separation during mitotic entry.

Mol Biol Cell 2019 Mar 6;30(7):876-886. Epub 2019 Mar 6.

Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514.

Across most sexually reproducing animals, centrosomes are provided to the oocyte through fertilization and must be positioned properly to establish the zygotic mitotic spindle. How centrosomes are positioned in space and time through the concerted action of key mitotic entry biochemical regulators, including protein phosphatase 2A (PP2A-B55/SUR-6), biophysical regulators, including dynein, and the nuclear lamina is unclear. Here, we uncover a role for PP2A-B55/SUR-6 in regulating centrosome separation. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0631DOI Listing
March 2019
6 Reads

Nestin in immature embryonic neurons affects axon growth cone morphology and Semaphorin3a sensitivity.

Mol Biol Cell 2019 Mar 6:mbcE18060361. Epub 2019 Mar 6.

Department of Cell Biology, University of Virginia, Charlottesville, VA 22908, USA.

Correct wiring in the neocortex requires that responses to an individual guidance cue vary among neurons in the same location, and within the same neuron over time. Nestin is an atypical intermediate filament expressed highly in neural progenitors and is thus used widely as a progenitor marker. Here we show a subpopulation of embryonic cortical neurons which transiently express nestin in their axons. Read More

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http://dx.doi.org/10.1091/mbc.E18-06-0361DOI Listing
March 2019
3 Reads

Retromer facilitates the localization of Bcl-xL to the mitochondrial outer membrane.

Mol Biol Cell 2019 Mar 6:mbcE19010044. Epub 2019 Mar 6.

The Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, 68198-5870.

The anti-apoptotic Bcl-2 family protein Bcl-xL plays a critical role in cell survival by protecting the integrity of the mitochondrial outer membrane (MOM). The mechanism through which Bcl-xL is recruited to the MOM has not been fully discerned. The retromer is a conserved endosomal scaffold complex involved in membrane trafficking. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E19-01-0044
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http://dx.doi.org/10.1091/mbc.E19-01-0044DOI Listing
March 2019
4 Reads

Correction.

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Mol Biol Cell 2019 Mar;30(5):729

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http://dx.doi.org/10.1091/mbc.E18-04-0253-corrDOI Listing

Life is sweet: the cell biology of glycoconjugates.

Mol Biol Cell 2019 Mar;30(5):525-529

Department of Biochemistry and Program in Cell and Molecular Biology, Duke University School of Medicine, Durham, NC 27710.

Cells are dazzling in their diversity, both within and across organisms. And yet, throughout this variety runs at least one common thread: sugars. All cells on Earth, in all domains of life, are literally covered in glycans, a term referring to the carbohydrate portion of glycoproteins and glycolipids. Read More

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https://www.molbiolcell.org/doi/10.1091/mbc.E18-04-0247
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http://dx.doi.org/10.1091/mbc.E18-04-0247DOI Listing
March 2019
5 Reads

EHD2 regulates adipocyte function and is enriched at cell surface-associated lipid droplets in primary human adipocytes.

Mol Biol Cell 2019 Feb 27:mbcE18100680. Epub 2019 Feb 27.

Department of Experimental Medical Science, Lund University, Lund, Sweden.

Adipocytes play a central role in energy balance, and dysfunctional adipose tissue severely affects systemic energy homeostasis. The ATPase EH domain-containing 2 (EHD2) has previously been shown to regulate caveolae, plasma membrane-specific domains that are involved in lipid uptake and signal transduction. Here, we investigated the role of EHD2 in adipocyte function. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0680DOI Listing
February 2019

Syntaxin 11 regulates the stimulus-dependent transport of Toll-like receptor 4 to the plasma membrane by cooperating with SNAP-23 in macrophages.

Mol Biol Cell 2019 Apr 27;30(9):1085-1097. Epub 2019 Feb 27.

Division of Molecular Biology, School of Life Sciences, Faculty of Medicine, Tottori University, Yonago, Tottori 683-8503, Japan.

Syntaxin 11 (stx11) is a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) that is selectively expressed in immune cells; however, its precise role in macrophages is unclear. We showed that stx11 knockdown reduces the phagocytosis of Escherichia coli in interferon-γ-activated macrophages. stx11 knockdown decreased Toll-like receptor 4 (TLR4) localization on the plasma membrane without affecting total expression. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0653DOI Listing
April 2019
1 Read

Regulation of LC3 lipidation by the autophagy-specific class III phosphatidylinositol-3 kinase complex.

Mol Biol Cell 2019 Apr 27;30(9):1098-1107. Epub 2019 Feb 27.

Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94270.

Autophagy is a conserved eukaryotic pathway critical for cellular adaptation to changes in nutrition levels and stress. The class III phosphatidylinositol (PI)3-kinase complexes I and II (PI3KC3-C1 and -C2) are essential for autophagosome initiation and maturation, respectively, from highly curved vesicles. We used a cell-free reaction that reproduces a key autophagy initiation step, LC3 lipidation, as a biochemical readout to probe the role of autophagy-related gene (ATG)14, a PI3KC3-C1-specific subunit implicated in targeting the complex to autophagy initiation sites. Read More

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http://dx.doi.org/10.1091/mbc.E18-11-0743DOI Listing
April 2019
1 Read

CEP135 isoform dysregulation promotes centrosome amplification in breast cancer cells.

Mol Biol Cell 2019 Feb 27:mbcE18100674. Epub 2019 Feb 27.

Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Avenue, Aurora, CO 80045-2537, USA.

The centrosome, comprised of two centrioles surrounded by pericentriolar material, is the cell's central microtubule organizing center. Centrosome duplication is coupled with the cell cycle such that centrosomes duplicate once in S phase. Loss of such coupling produces supernumerary centrosomes, a condition called centrosome amplification (CA). Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0674DOI Listing
February 2019

Lymphatic endothelial cell calcium pulses are sensitive to spatial gradients in wall shear stress.

Mol Biol Cell 2019 Mar 27;30(7):923-931. Epub 2019 Feb 27.

Department of Chemical Engineering, Stanford University, Stanford, CA 94305.

Cytosolic calcium (Ca) is a ubiquitous second messenger that influences numerous aspects of cellular function. In many cell types, cytosolic Ca concentrations are characterized by periodic pulses, whose dynamics can influence downstream signal transduction. Here, we examine the general question of how cells use Ca pulses to encode input stimuli in the context of the response of lymphatic endothelial cells (LECs) to fluid flow. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0618DOI Listing

Isoform-specific Ras signaling is growth factor dependent.

Mol Biol Cell 2019 Apr 20;30(9):1108-1117. Epub 2019 Feb 20.

Division of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom.

HRAS, NRAS, and KRAS isoforms are almost identical proteins that are ubiquitously expressed and activate a common set of effectors. In vivo studies have revealed that they are not biologically redundant; however, the isoform specificity of Ras signaling remains poorly understood. Using a novel panel of isogenic SW48 cell lines endogenously expressing wild-type or G12V-mutated activated Ras isoforms, we have performed a detailed characterization of endogenous isoform-specific mutant Ras signaling. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0676DOI Listing
April 2019
5 Reads

The relationship between metastatic potential and in vitro mechanical properties of osteosarcoma cells.

Mol Biol Cell 2019 Mar 20;30(7):887-898. Epub 2019 Feb 20.

Biomechanics Laboratory, University Hospital Balgrist, University of Zürich, 8008 Zürich, Switzerland.

Osteosarcoma is the most frequent primary tumor of bone and is characterized by its high tendency to metastasize in lungs. Although treatment in cases of early diagnosis results in a 5-yr survival rate of nearly 60%, the prognosis for patients with secondary lesions at diagnosis is poor, and their 5-yr survival rate remains below 30%. In the present work, we have used a number of analytical methods to investigate the impact of increased metastatic potential on the biophysical properties and force generation of osteosarcoma cells. Read More

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http://dx.doi.org/10.1091/mbc.E18-08-0545DOI Listing
March 2019
2 Reads
4.466 Impact Factor

Choice between 1- and 2-furrow cytokinesis in Caenorhabditis elegans embryos with tripolar spindles.

Mol Biol Cell 2019 Feb 20:mbcE19010075. Epub 2019 Feb 20.

Cell Architecture Laboratory, Department of Chromosome Science, National Institute of Genetics, Yata 1111, Mishima, Shizuoka 411-8540, Japan.

Excessive centrosomes often lead to multipolar spindles, and thus probably to multipolar mitosis and aneuploidy. In Caenorhabditis elegans, approximately 70% of the paternal emb-27 mutant embryonic cells contained more than two centrosomes and formed multipolar spindles. However, only 30% of the cells with tripolar spindles formed two cytokinetic furrows. Read More

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http://dx.doi.org/10.1091/mbc.E19-01-0075DOI Listing
February 2019

Myosin IIA drives membrane bleb retraction.

Mol Biol Cell 2019 Apr 20;30(9):1051-1059. Epub 2019 Feb 20.

Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232.

Membrane blebs are specialized cellular protrusions that play diverse roles in processes such as cell division and cell migration. Blebbing can be divided into three distinct phases: bleb nucleation, bleb growth, and bleb retraction. Following nucleation and bleb growth, the actin cortex, comprising actin, cross-linking proteins, and nonmuscle myosin II (MII), begins to reassemble on the membrane. Read More

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http://dx.doi.org/10.1091/mbc.E18-11-0752DOI Listing

Cellular Crowding Influences Extrusion and Proliferation to Facilitate Epithelial Tissue Repair.

Mol Biol Cell 2019 02 20:mbcE18050295. Epub 2019 Feb 20.

Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030.

Epithelial wound healing requires a complex orchestration of cellular rearrangements and movements to restore tissue architecture and function after injury. While it is well-known that mechanical forces can affect tissue morphogenesis and patterning, how the biophysical cues generated after injury influence cellular behaviors during tissue repair is not well understood. Using time-lapse confocal imaging of epithelial tissues in living zebrafish larvae, we provide evidence that localized increases in cellular crowding during wound closure promote the extrusion of non-apoptotic cells via mechanically regulated stretch-activated ion channels (SACs). Read More

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http://dx.doi.org/10.1091/mbc.E18-05-0295DOI Listing
February 2019

The putative G protein-coupled receptor GrlD mediates extracellular polyphosphate sensing in Dictyostelium discoideum.

Mol Biol Cell 2019 Apr 20;30(9):1118-1128. Epub 2019 Feb 20.

Department of Biology, Texas A&M University, College Station, TX 77843-3474.

Five or more orthophosphates bound together by high-energy phosphoanhydride bonds are highly ubiquitous inorganic molecules called polyphosphate. Polyphosphate acts as a signaling molecule eliciting a number of responses in eukaryotic cells, but the mechanisms mediating these effects are poorly understood. Proliferating Dictyostelium discoideum cells accumulate extracellular polyphosphate. Read More

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http://dx.doi.org/10.1091/mbc.E18-10-0686DOI Listing