Página 13 dos resultados de 6914 itens digitais encontrados em 0.018 segundos

‣ Multiple roles of the cytoskeleton in autophagy

Monastyrska, Iryna; Rieter, Ester; Klionsky, Daniel J.; Reggiori, Fulvio
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2009 Português
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Autophagy is involved in a wide range of physiological processes including cellular remodeling during development, immuno-protection against heterologous invaders and elimination of aberrant or obsolete cellular structures. This conserved degradation pathway also plays a key role in maintaining intracellular nutritional homeostasis and during starvation, for example, it is involved in the recycling of unnecessary cellular components to compensate for the limitation of nutrients. Autophagy is characterized by specific membrane rearrangements that culminate with the formation of large cytosolic double-membrane vesicles called autophagosomes. Autophagosomes sequester cytoplasmic material that is destined for degradation. Once completed, these vesicles dock and fuse with endosomes and/or lysosomes to deliver their contents into the hydrolytically active lumen of the latter organelle where, together with their cargoes, they are broken down into their basic components. Specific structures destined for degradation via autophagy are in many cases selectively targeted and sequestered into autophagosomes.

‣ Septin structure and function in yeast and beyond

Oh, Younghoon; Bi, Erfei
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
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Septins are conserved GTP-binding proteins that assemble into hetero-oligomeric complexes and higher-order structures such as filaments, rings, hourglasses or gauzes. Septins are usually associated with a discrete region of the plasma membrane and function as a cellular scaffold or diffusion barrier to effect cytokinesis, cell polarity, and many other cellular functions. Recent structural studies of septin complexes have provided mechanistic insights into septin filament assembly, but key questions about the assembly, dynamics, and function of different septin cellular structures remain largely unanswered.

‣ A Symphony of Regulations Centered on p63 to Control Development of Ectoderm-Derived Structures

Guerrini, Luisa; Costanzo, Antonio; Merlo, Giorgio R.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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The p53-related transcription factor p63 is critically important for basic cellular functions during development of the ectoderm and derived structure and tissues, including skin, limb, palate, and hair. On the one side, p63 is required to sustain the proliferation of keratinocyte progenitors, while on the other side it is required for cell stratification, commitment to differentiate, cell adhesion, and epithelial-mesenchymal signaling. Molecules that are components or regulators of the p63 pathway(s) are rapidly being identified, and it comes with no surprise that alterations in the p63 pathway lead to congenital conditions in which the skin and other ectoderm-derived structures are affected. In this paper, we summarize the current knowledge of the molecular and cellular regulations centered on p63, derived from the comprehension of p63-linked human diseases and the corresponding animal models, as well as from cellular models and high-throughput molecular approaches. We point out common themes and features, that allow to speculate on the possible role of p63 downstream events and their potential exploitation in future attempts to correct the congenital defect in preclinical studies.

‣ Understanding Cellular Mechanisms Underlying Airway Epithelial Repair: Selecting the Most Appropriate Animal Models

Yahaya, B.
Fonte: The Scientific World Journal Publicador: The Scientific World Journal
Tipo: Artigo de Revista Científica
Publicado em 23/09/2012 Português
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Understanding the mechanisms underlying the process of regeneration and repair of airway epithelial structures demands close characterization of the associated cellular and molecular events. The choice of an animal model system to study these processes and the role of lung stem cells is debatable since ideally the chosen animal model should offer a valid comparison with the human lung. Species differences may include the complex three-dimensional lung structures, cellular composition of the lung airway as well as transcriptional control of the molecular events in response to airway epithelium regeneration, and repair following injury. In this paper, we discuss issues related to the study of the lung repair and regeneration including the role of putative stem cells in small- and large-animal models. At the end of this paper, the author discuss the potential for using sheep as a model which can help bridge the gap between small-animal model systems and humans.

‣ Antibody-linked Spherical Nucleic Acids for Cellular Targeting

Zhang, Ke; Hao, Liangliang; Hurst, Sarah J.; Mirkin, Chad A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
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Spherical nucleic acid (SNAs) constructs are promising new single entity gene regulation materials capable of both cellular transfection and gene knockdown, but thus far are promiscuous structures, exhibiting excellent genetic but little cellular selectivity. In this communication, we describe a strategy to impart targeting capabilities to these constructs through non-covalent functionalization with a complementary antibody-DNA conjugate. As a proof-of concept, we designed HER2-targeting SNAs and demonstrated that such structures exhibit cell type selectivity in terms of their uptake, and significantly greater gene knockdown in cells overexpressing the target antigen as compared to the analogous antibody-free and off-target materials.

‣ Integrated Electron Microscopy: Super-Duper Resolution

Krijnse Locker, Jacomine; Schmid, Sandra L.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
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Since its inception, electron microscopy (EM) has revealed that cellular membranes are organized into structurally distinct subdomains, created by localized protein and lipid assemblies to perform specific complex cellular functions. Caveolae are membrane subdomains that function as signaling platforms, endocytic carriers, sensors of membrane tension, and mechanical stress, as well as in lipid homeostasis. They were first discovered almost 60 years ago by pioneering electron microscopists. While new and exciting developments in SUPER-resolution fluorescent light microscopy facilitate studies of the spatial organization of fluorescently labeled protein components, these techniques cannot reveal the underlying cellular structures. Thus, equally exciting are developments in EM: genetically encoded probes for protein localization at sub-10 nm resolution, more powerful instruments that allow imaging of larger cell volumes, and computational methods for reconstructing three-dimensional images. Used in combination, as done by Ludwig et al. in the current issue of PLOS Biology, these tools reveal high-resolution insights into the composition and organization of the caveolae coat and the formation of these specialized structures. Together, these advances are contributing to a resurgence in EM.

‣ Oligomerization and higher-order assembly contribute to sub-cellular localization of a bacterial scaffold

Bowman, Grant R.; Perez, Adam M.; Ptacin, Jerod L.; Ighodaro, Eseosa; Folta-Stogniew, Ewa; Comolli, Luis R.; Shapiro, Lucy
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
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In Caulobacter crescentus, the PopZ polar scaffold protein supports asymmetric cell division by recruiting distinct sets of binding partners to opposite cell poles. To understand how polar organizing centers are established by PopZ, we investigated a set of mutated PopZ proteins for defects in sub-cellular localization and recruitment activity. We identified a domain within the C-terminal 76 amino acids that is necessary and sufficient for accumulation as a single subcellular focus, a domain within the N-terminal 23 amino acids that is necessary for bipolar targeting, and a linker domain between these localization determinants that tolerates large variation. Mutations that inhibited dynamic PopZ localization inhibited the recruitment of other factors to cell poles. Mutations in the C-terminal domain also blocked discrete steps in the assembly of higher-order structures. Biophysical analysis of purified wildtype and assembly-defective mutant proteins indicates that PopZ self-associates into an elongated trimer, which readily forms a dimer of trimers through lateral contact. The final six amino acids of PopZ are necessary for connecting the hexamers into filaments, and these structures are important for sub-cellular localization. Thus...

‣ Hox Targets and Cellular Functions

Sánchez-Herrero, Ernesto
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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Hox genes are a group of genes that specify structures along the anteroposterior axis in bilaterians. Although in many cases they do so by modifying a homologous structure with a different (or no) Hox input, there are also examples of Hox genes constructing new organs with no homology in other regions of the body. Hox genes determine structures though the regulation of targets implementing cellular functions and by coordinating cell behavior. The genetic organization to construct or modify a certain organ involves both a genetic cascade through intermediate transcription factors and a direct regulation of targets carrying out cellular functions. In this review I discuss new data from genome-wide techniques, as well as previous genetic and developmental information, to describe some examples of Hox regulation of different cell functions. I also discuss the organization of genetic cascades leading to the development of new organs, mainly using Drosophila melanogaster as the model to analyze Hox function.

‣ Involvement of autophagy in the direct ER to vacuole protein trafficking route in plants

Michaeli, Simon; Avin-Wittenberg, Tamar; Galili, Gad
Fonte: Front. Plant Sci. Publicador: Front. Plant Sci.
Tipo: Artigo de Revista Científica
Publicado em 08/04/2014 Português
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Trafficking of proteins from the endoplasmic reticulum (ER) to the vacuole is a fundamental process in plants, being involved both in vacuole biogenesis as well as with plant growth and response to environmental stresses. Although the canonical transport of cellular components from the ER to the vacuole includes the Golgi apparatus as an intermediate compartment, there are multiple lines of evidence that support the existence of a direct ER-to-vacuole, Golgi-independent, trafficking route in plants that uses the autophagy machinery. Plant autophagy was initially described by electron microscopy, visualizing cellular structures that are morphologically reminiscent of autophagosomes. In some of these reports these structures were shown to transport vacuole residing proteins, particularly seed storage proteins, directly from the ER to the vacuole. More recently, following the discovery of the proteins of the core autophagy machinery, molecular tools were implemented in deciphering the involvement of autophagy in this special trafficking route. Here we review the relatively older and more recent scientific observations, supporting the involvement of autophagy in the special cellular trafficking pathways of plants.

‣ Involvement of the Iron Regulatory Protein from Eisenia andrei Earthworms in the Regulation of Cellular Iron Homeostasis

Procházková, Petra; Škanta, František; Roubalová, Radka; Šilerová, Marcela; Dvořák, Jiří; Bilej, Martin
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/10/2014 Português
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Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs) that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs) of the 5′- or 3′-untranslated regions (UTR) of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP). The earthworm IRE site in 5′-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis...

‣ Molecular and cellular functions of the FANCJ DNA helicase defective in cancer and in Fanconi anemia

Brosh, Robert M.; Cantor, Sharon B.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 21/10/2014 Português
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The FANCJ DNA helicase is mutated in hereditary breast and ovarian cancer as well as the progressive bone marrow failure disorder Fanconi anemia (FA). FANCJ is linked to cancer suppression and DNA double strand break repair through its direct interaction with the hereditary breast cancer associated gene product, BRCA1. FANCJ also operates in the FA pathway of interstrand cross-link repair and contributes to homologous recombination. FANCJ collaborates with a number of DNA metabolizing proteins implicated in DNA damage detection and repair, and plays an important role in cell cycle checkpoint control. In addition to its role in the classical FA pathway, FANCJ is believed to have other functions that are centered on alleviating replication stress. FANCJ resolves G-quadruplex (G4) DNA structures that are known to affect cellular replication and transcription, and potentially play a role in the preservation and functionality of chromosomal structures such as telomeres. Recent studies suggest that FANCJ helps to maintain chromatin structure and preserve epigenetic stability by facilitating smooth progression of the replication fork when it encounters DNA damage or an alternate DNA structure such as a G4. Ongoing studies suggest a prominent but still not well-understood role of FANCJ in transcriptional regulation...

‣ A High-Performance Cellular Automaton Model of Tumor Growth with Dynamically Growing Domains

Poleszczuk, Jan; Enderling, Heiko
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/2014 Português
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Tumor growth from a single transformed cancer cell up to a clinically apparent mass spans many spatial and temporal orders of magnitude. Implementation of cellular automata simulations of such tumor growth can be straightforward but computing performance often counterbalances simplicity. Computationally convenient simulation times can be achieved by choosing appropriate data structures, memory and cell handling as well as domain setup. We propose a cellular automaton model of tumor growth with a domain that expands dynamically as the tumor population increases. We discuss memory access, data structures and implementation techniques that yield high-performance multi-scale Monte Carlo simulations of tumor growth. We discuss tumor properties that favor the proposed high-performance design and present simulation results of the tumor growth model. We estimate to which parameters the model is the most sensitive, and show that tumor volume depends on a number of parameters in a non-monotonic manner.

‣ Chemoselective silicification of synthetic peptides and polyamines

Abacilar, Maryna; Daus, Fabian; Geyer, Armin
Fonte: Beilstein-Institut Publicador: Beilstein-Institut
Tipo: Artigo de Revista Científica
Publicado em 08/01/2015 Português
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Biosilicification sets the standard for the localized in vitro precipitation of silica at low orthosilicate concentrations in aqueous environment under ambient conditions. Numerous parameters must be controlled for the development of new technologies in designing inventive nanosilica structures, which are able to challenge the biological templates. A long neglected requirement that came into focus in the recent years are the cellular techniques of preventing unintentional lithification of cellular structures since numerous cellular components such as membranes, DNA, and proteins are known to precipitate nanosilica. The diatom metabolism makes use of techniques that restrict silicification to an armor of silica around the cell wall while avoiding the petrifying gaze of Medusa, which turns the whole cell into stone. Step by step, biochemistry unveils the hierarchical interplay of an arsenal of low-molecular weight molecules, proteins, and the cytoskeletal architecture and it becomes clearer why the organisms invest much metabolic effort for an obviously simple chemical reaction like the precipitation of amorphous silica. The discrimination between different soluble components in the silicification process (chemoselective silicification) is not only vitally important for the diatom but poses an interesting challenge for in vitro experiments. Until now...

‣ Sequential Superresolution Imaging of Multiple Targets Using a Single Fluorophore

Valley, Christopher C.; Liu, Sheng; Lidke, Diane S.; Lidke, Keith A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 10/04/2015 Português
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Fluorescence superresolution (SR) microscopy, or fluorescence nanoscopy, provides nanometer scale detail of cellular structures and allows for imaging of biological processes at the molecular level. Specific SR imaging methods, such as localization-based imaging, rely on stochastic transitions between on (fluorescent) and off (dark) states of fluorophores. Imaging multiple cellular structures using multi-color imaging is complicated and limited by the differing properties of various organic dyes including their fluorescent state duty cycle, photons per switching event, number of fluorescent cycles before irreversible photobleaching, and overall sensitivity to buffer conditions. In addition, multiple color imaging requires consideration of multiple optical paths or chromatic aberration that can lead to differential aberrations that are important at the nanometer scale. Here, we report a method for sequential labeling and imaging that allows for SR imaging of multiple targets using a single fluorophore with negligible cross-talk between images. Using brightfield image correlation to register and overlay multiple image acquisitions with ~10 nm overlay precision in the x-y imaging plane, we have exploited the optimal properties of AlexaFluor647 for dSTORM to image four distinct cellular proteins. We also visualize the changes in co-localization of the epidermal growth factor (EGF) receptor and clathrin upon EGF addition that are consistent with clathrin-mediated endocytosis. These results are the first to demonstrate sequential SR (s-SR) imaging using direct stochastic reconstruction microscopy (dSTORM)...

‣ Three-dimensional morphogenesis of MDCK cells induced by cellular contractile forces on a viscous substrate

Imai, Misako; Furusawa, Kazuya; Mizutani, Takeomi; Kawabata, Kazushige; Haga, Hisashi
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 16/09/2015 Português
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Substrate physical properties are essential for many physiological events such as embryonic development and 3D tissue formation. Physical properties of the extracellular matrix such as viscoelasticity and geometrical constraints are understood as factors that affect cell behaviour. In this study, we focused on the relationship between epithelial cell 3D morphogenesis and the substrate viscosity. We observed that Madin-Darby Canine Kidney (MDCK) cells formed 3D structures on a viscous substrate (Matrigel). The structures appear as a tulip hat. We then changed the substrate viscosity by genipin (GP) treatment. GP is a cross-linker of amino groups. Cells cultured on GP-treated-matrigel changed their 3D morphology in a substrate viscosity-dependent manner. Furthermore, to elucidate the spatial distribution of the cellular contractile force, localization of mono-phosphorylated and di-phosphorylated myosin regulatory light chain (P-MRLCs) was visualized by immunofluorescence. P-MRLCs localized along the periphery of epithelial sheets. Treatment with Y-27632, a Rho-kinase inhibitor, blocked the P-MRLCs localization at the edge of epithelial sheets and halted 3D morphogenesis. Our results indicate that the substrate viscosity, the substrate deformation...

‣ Morpho : a self-deformable modular robot inspired by cellular structure; Self-deformable modular robot inspired by cellular structure

Haller, Kristina M. (Kristina Marie)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 16 leaves
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In this paper, we present a modular robot design inspired by the creation of complex structures and functions in biology via deformation. Our design is based on the Tensegrity model of cellular structure, where active filaments within the cell contract and expand to control individual cell shape, and sheets of such cells undergo large-scale shape change through the cooperative action of connected cells. Such deformations play a role in many processes: early embryo shape change, heart and intestine function, and in lamprey locomotion. Modular robotic systems that replicate the basic deformable multicellular structure have the potential to quickly generate large-scale shape change and create time-varying shapes to achieve different global functions. We present a design and initial hardware implementation of this model. Our design includes four different modular components: (1) actuating links, (2) passive (compressive) links, (3) elastic surface membranes, and (4) universal connecting interfaces. In both hardware implementation and simulation, we show several self-deformable structures that can be generated from these four components, including the deformable surface, expandable cube, terrain-adaptive bridge from [1] and some examples inspired by biology. We argue that self-deformation is more appropriate for dynamic and sensing-adaptive shape change in a certain class of tasks.; by Kristina M. Haller.; Thesis (S.B.)--Massachusetts Institute of Technology...

‣ Bayesian multi-target tracking: application to total internal reflection fluorescence microscopy

Rezatofighi, Seyed Hamid
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD)
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This thesis focuses on the problem of automated tracking of tiny cellular and sub-cellular structures, known as particles, in the sequences acquired from total internal reflection fluorescence microscopy (TIRFM) imaging technique. Our primary biological motivation is to develop an automated system for tracking the sub-cellular structures involving exocytosis (an intracellular mechanism) which is helpful for studying the possible causes of the defects in diseases such as diabetes and obesity. However, all methods proposed in this thesis are generalized to be applicable for a wide range of particle tracking applications. A reliable multi-particle tracking method should be capable of tracking numerous similar objects in the presence of high levels of noise, high target density and complex motions and interactions. In this thesis, we choose the Bayesian filtering framework as our main approach to deal with this problem. We focus on the approaches that work based on detections. Therefore, in this thesis, we first propose a method that robustly detects the particles in the noisy TIRFM sequences with inhomogeneous and time-varying background. In order to evaluate our detection and tracking methods on the sequences with known and reliable ground truth...

‣ Proper Cellular Reorganization during Drosophila Spermatid Individualization Depends on Actin Structures Composed of Two Domains, Bundles and Meshwork, That Are Differentially Regulated and Have Different Functions

Noguchi, Tatsuhiko; Lenartowska, Marta; Rogat, Aaron D.; Frank, Deborah J.; Miller, Kathryn G.
Fonte: The American Society for Cell Biology Publicador: The American Society for Cell Biology
Tipo: Artigo de Revista Científica
Publicado em /06/2008 Português
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During spermatid individualization in Drosophila, actin structures (cones) mediate cellular remodeling that separates the syncytial spermatids into individual cells. These actin cones are composed of two structural domains, a front meshwork and a rear region of parallel bundles. We show here that the two domains form separately in time, are regulated by different sets of actin-associated proteins, can be formed independently, and have different roles. Newly forming cones were composed only of bundles, whereas the meshwork formed later, coincident with the onset of cone movement. Polarized distributions of myosin VI, Arp2/3 complex, and the actin-bundling proteins, singed (fascin) and quail (villin), occurred when movement initiated. When the Arp2/3 complex was absent, meshwork formation was compromised, but surprisingly, the cones still moved. Despite the fact that the cones moved, membrane reorganization and cytoplasmic exclusion were abnormal and individualization failed. In contrast, when profilin, a regulator of actin assembly, was absent, bundle formation was greatly reduced. The meshwork still formed, but no movement occurred. Analysis of this actin structure's formation and participation in cellular reorganization provides insight into how the mechanisms used in cell motility are modified to mediate motile processes within specialized cells.

‣ Delineating the Tes Interaction Site in Zyxin and Studying Cellular Effects of Its Disruption

Hadzic, Ermin; Catillon, Marie; Halavatyi, Aliaksandr; Medves, Sandrine; Van Troys, Marleen; Moes, Michèle; Baird, Michelle A.; Davidson, Michael W.; Schaffner-Reckinger, Elisabeth; Ampe, Christophe; Friederich, Evelyne
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 28/10/2015 Português
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Focal adhesions are integrin-based structures that link the actin cytoskeleton and the extracellular matrix. They play an important role in various cellular functions such as cell signaling, cell motility and cell shape. To ensure and fine tune these different cellular functions, adhesions are regulated by a large number of proteins. The LIM domain protein zyxin localizes to focal adhesions where it participates in the regulation of the actin cytoskeleton. Because of its interactions with a variety of binding partners, zyxin has been proposed to act as a molecular scaffold. Here, we studied the interaction of zyxin with such a partner: Tes. Similar to zyxin, Tes harbors three highly conserved LIM domains of which the LIM1 domain directly interacts with zyxin. Using different zyxin variants in pull-down assays and ectopic recruitment experiments, we identified the Tes binding site in zyxin and showed that four highly conserved amino acids are crucial for its interaction with Tes. Based upon these findings, we used a zyxin mutant defective in Tes-binding to assess the functional consequences of abrogating the zyxin-Tes interaction in focal adhesions. Performing fluorescence recovery after photobleaching, we showed that zyxin recruits Tes to focal adhesions and modulates its turnover in these structures. However...

‣ Traffic of Secondary Metabolites to Cell Surface in the Red Alga Laurencia dendroidea Depends on a Two-Step Transport by the Cytoskeleton

Reis, Vanessa M.; Oliveira, Louisi S.; Passos, Raoni M. F.; Viana, Nathan B.; Mermelstein, Cláudia; Sant'Anna, Celso; Pereira, Renato C.; Paradas, Wladimir C.; Thompson, Fabiano L.; Amado-Filho, Gilberto M.; Salgado, Leonardo T.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 21/05/2013 Português
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In Laurencia dendroidea, halogenated secondary metabolites are primarily located in the vacuole named the corps en cerise (CC). For chemical defence at the surface level, these metabolites are intracellularly mobilised through vesicle transport from the CC to the cell periphery for posterior exocytosis of these chemicals. The cell structures involved in this specific vesicle traffic as well as the cellular structures related to the positioning and anchoring of the CC within the cell are not well known. Here, we aimed to investigate the role of cytoskeletal elements in both processes. Cellular and molecular assays were conducted to i) determine the ultrastructural apparatus involved in the vesicle traffic, ii) localise cytoskeletal filaments, iii) evaluate the role of different cytoskeletal filaments in the vesicle transport, iv) identify the cytoskeletal filaments responsible for the positioning and anchoring of the CC, and v) identify the transcripts related to cytoskeletal activity and vesicle transport. Our results show that microfilaments are found within the connections linking the CC to the cell periphery, playing an essential role in the vesicle traffic at these connections, which means a first step of the secondary metabolites transport to the cell surface. After that...