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Adhesive Junction
The Experts below are selected from a list of 141 Experts worldwide ranked by ideXlab platform
Michael L. Dustin – One of the best experts on this subject based on the ideXlab platform.
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Visualization of cell‑cell interaction contacts: Synapses and kinapses
Self nonself, 2011Co-Authors: Michael L. DustinAbstract:T-cell activation requires interactions of T-cell antigen receptors (TCR) and peptides presented by major histhistocompatibility complex molecules (MHCp) in an Adhesive Junction between the T-cell and antigen-presenting cell (APC). Stable Junctions with bull’s eye supramolecular activation clusters (SMACs) have been defined as immunological synapses. The term synapse works in this case because it joins roots for “same” and “fasten,” which could be translated as “fasten in the same place.” These structures maintain T-cell-APC interaction and allow directed secretion. We have proposed that SMACs are not really clusters, but are analogous to higher order membrane-cytoskeleton zones involved in amoeboid locomotion including a substrate testing lamellipodium, an Adhesive lamella and anti-Adhesive uropod. Since T-cells can also integrate signaling during locomotion over antigen presenting cells, it is important to consider Adhesive Junctions maintained as cells move past each other. This combination of movement (kine-) and fastening (-apse) can be described as a kinapse or moving Junction. Synapses and kinapses operate in different stages of T-cell priming. Optimal effector functions may also depend upon cyclical use of synapses and kinapses. Visualization of these structures in vitro and in vivo presents many distinct challenges that will be discussed in this chapter.
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HIV-1 Virological Synapse is not Simply a Copycat of the Immunological Synapse
Viruses, 2010Co-Authors: Gaia Vasiliver-shamis, Michael L. Dustin, Catarina E. HioeAbstract:The virological synapse (VS) is a tight Adhesive Junction between an HIV-infected cell and an uninfected target cell, across which virus can be efficiently transferred from cell to cell in the absence of cell-cell fusion. The VS has been postulated to resemble, in its morphology, the well-studied immunological synapse (IS). This review article discusses the structural similarities between IS and VS and the shared T cellcell receptor (TCR) signaling components that are found in the VS. However, the IS and the VS display distinct kinetics in disassembly and intracellular signaling events, possibly leading to different biological outcomes. Hence, HIV-1 exploits molecular components of IS and TCR signaling machinery to trigger unique changes in cellular morphology, migration, and activation that facilitate its transmission and cell-to-cell spread.
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Visualization of cell-cell interaction contacts-synapses and kinapses.
Advances in experimental medicine and biology, 2008Co-Authors: Michael L. DustinAbstract:T-cell activation requires interactions of T-cell antigen receptors (TCR) and peptides presented by major histhistocompatibility complex molecules (MHCp) in an Adhesive Junction between the T-cell and antigen-presenting cell (APC). Stable Junctions with bull’s eye supramolecular activation clusters (SMACs) have been defined as immunological synapses. The term synapse works in this case because it joins roots for “same” and “fasten”, which could be translated as “fasten in the same place”. These structures maintain T-cell-APC interaction and allow directed secretion. We have proposed that SMACs are not really clusters, but are analogous to higher order membrane-cytoskeleton zones involved in amoeboid locomotion including a substrate testing lamellipodium, an Adhesive lamella and anti-Adhesive uropod. Since T-cells can also integrate signaling during locomotion over antigen presenting cells, it is important to consider Adhesive Junctions maintained as cells move past each other. This combination of movement (kine-) and fastening (-apse) can be described as a kinapse or moving Junction. Synapses and kinapses operate in different stages of T-cell priming. Optimal effector functions may also depend upon cyclical use of synapses and kinapses. Visualization of these structures in vitro and in vivo presents many distinct challenges that will be discussed in this chapter.
Mark Peifer – One of the best experts on this subject based on the ideXlab platform.
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δ catenin an Adhesive Junction associated protein which promotes cell scattering
Journal of Cell Biology, 1999Co-Authors: Mercedes F Paredes, Miguel Medina, Jianhua Zhou, Robert Cavallo, Mark Peifer, Lisa D Orecchio, Kenneth S KosikAbstract:The classical adherens Junction that holds epithelial cells together consists of a protein complex in which members of the cadherin family linked to various catenins are the principal components. δ-catenin is a mammalian brain protein in the Armadillo repeat superfamily with sequence similarity to the adherens Junction protein p120ctn. We found that δ-catenin can be immunoprecipitated as a complex with other components of the adherens Junction, including cadherin and β-catenin, from transfected cells and brain. The interaction with cadherin involves direct contact within the highly conserved juxtamembrane region of the COOH terminus, where p120ctn also binds. In developing mouse brain, staining with δ-catenin antibodies is prominent towards the apical boundary of the neuroepithelial cells in the ventricular zone. When transfected into Madin-Darby canine kidney (MDCK) epithelial cells δ-catenin colocalized with cadherin, p120ctn, and β-catenin. The Arm domain alone was sufficient for achieving localization and coimmunoprecipitation with cadherin. The ectopic expression of δ-catenin in MDCK cells altered their morphology, induced the elaboration of lamellipodia, interfered with monolayer formation, and increased scattering in response to hepatocyte growth factor treatment. We propose that δ-catenin can regulate adhesion molecules to implement the organization of large cellular arrays necessary for tissue morphogenesis. * APC : adenomatous polypolyposisi BrdU : 5-bromo-2′-deoxy-uridine GFP : green fluorescent protein HGF : hepatocyte growth factor IP : immunoprecipitation MF : δ-catenin–transfected MDCK
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δ-catenin, an Adhesive Junction–associated Protein Which Promotes Cell Scattering
The Journal of cell biology, 1999Co-Authors: Mercedes F Paredes, Miguel Medina, Jianhua Zhou, Robert Cavallo, Mark Peifer, Lisa D Orecchio, Kenneth S KosikAbstract:The classical adherens Junction that holds epithelial cells together consists of a protein complex in which members of the cadherin family linked to various catenins are the principal components. δ-catenin is a mammalian brain protein in the Armadillo repeat superfamily with sequence similarity to the adherens Junction protein p120ctn. We found that δ-catenin can be immunoprecipitated as a complex with other components of the adherens Junction, including cadherin and β-catenin, from transfected cells and brain. The interaction with cadherin involves direct contact within the highly conserved juxtamembrane region of the COOH terminus, where p120ctn also binds. In developing mouse brain, staining with δ-catenin antibodies is prominent towards the apical boundary of the neuroepithelial cells in the ventricular zone. When transfected into Madin-Darby canine kidney (MDCK) epithelial cells δ-catenin colocalized with cadherin, p120ctn, and β-catenin. The Arm domain alone was sufficient for achieving localization and coimmunoprecipitation with cadherin. The ectopic expression of δ-catenin in MDCK cells altered their morphology, induced the elaboration of lamellipodia, interfered with monolayer formation, and increased scattering in response to hepatocyte growth factor treatment. We propose that δ-catenin can regulate adhesion molecules to implement the organization of large cellular arrays necessary for tissue morphogenesis. * APC : adenomatous polypolyposisi BrdU : 5-bromo-2′-deoxy-uridine GFP : green fluorescent protein HGF : hepatocyte growth factor IP : immunoprecipitation MF : δ-catenin–transfected MDCK
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a role for the drosophila segment polarity gene armadillo in cell adhesion and cytoskeletal integrity during oogenesis
Development, 1993Co-Authors: Mark Peifer, Sandra Orsulic, Dari Sweeton, Eric WieschausAbstract:The epithelial sheet is a structural unit common to many tissues. Its organization appears to depend on the function of the multi-protein complexes that form adherens Junctions. Elegant cell biological experiments have provided support for hypotheses explaining the function of adherens Junctions and of their components. These systems, however, lack the ability to test function within an entire organism during development. The realization that the product of the Drosophila segment polarity gene armadillo is related to the vertebrate Adhesive Junction components plakoglobin and beta-catenin led to the suggestion that armadillo might provide a genetic handle to study Adhesive Junction structure and function. An examination of the potential function of Armadillo in cell-cell Adhesive Junctions was initiated using the Drosophila ovary as the model system. We examined the distribution of Armadillo in the Drosophila ovary and demonstrated that this localization often parallels the location of cell-cell Adhesive Junctions. The consequences of removing armadillo function from the germ-line cells of the ovary were also examined. Germ-line armadillo mutations appear to disrupt processes requiring cell adheadhesion and integrity of the actin cytoskeleton, consistent with a role for Armadillo in cell-cell Adhesive Junctions. We have also used armadillo mutations to examine the effects on ovarian development of altering the stereotyped cell arrangements of the ovary. The implications of these results for the role of Adhesive Junctions during development are discussed.
Masayasu Nomura – One of the best experts on this subject based on the ideXlab platform.
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yeast srp1p has homology to armadillo plakoglobin beta catenin and participates in apparently multiple nuclear functions including the maintenance of the nucleolar structure
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: Ryoji Yano, Melanie Oakes, Michelle M Tabb, Masayasu NomuraAbstract:Abstract SRP1, a suppressor of certain temperature-sensitive mutations in RNA polypolymerasea> in Saccharomyces cerevisiae, encodes a protein that is associated with nuclear pores. By using a system of conditional SRP1 expression and by isolating temperature-sensitive srp1 mutants, we have demonstrated that Srp1p is essential for maintenance of the crescent-shaped nucleolar structure, RNA transcription, and the proper functions of microtubules as inferred from analysis of nuclear division/segregation and immunofluorescence microscopy of microtubules. Different mutant alleles showed significantly different phenotypes in relation to these apparently multiple functional roles of the protein. We have also found that eight imperfect 42-amino-acid tandem repeats present in Srp1p are similar to the 42-amino-acid repeats in armadillo/plakoglobin/beta-catenin proteins present in Adhesive Junction complexes of higher eukaryotes. We discuss this similarity in connection with the observed pleiotropic effects of srp1 mutations.
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Yeast Srp1p has homology to armadillo/plakoglobin/beta-catenin and participates in apparently multiple nuclear functions including the maintenance of the nucleolar structure
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: Ryoji Yano, Melanie Oakes, Michelle M Tabb, Masayasu NomuraAbstract:Abstract SRP1, a suppressor of certain temperature-sensitive mutations in RNA polypolymerasea> in Saccharomyces cerevisiae, encodes a protein that is associated with nuclear pores. By using a system of conditional SRP1 expression and by isolating temperature-sensitive srp1 mutants, we have demonstrated that Srp1p is essential for maintenance of the crescent-shaped nucleolar structure, RNA transcription, and the proper functions of microtubules as inferred from analysis of nuclear division/segregation and immunofluorescence microscopy of microtubules. Different mutant alleles showed significantly different phenotypes in relation to these apparently multiple functional roles of the protein. We have also found that eight imperfect 42-amino-acid tandem repeats present in Srp1p are similar to the 42-amino-acid repeats in armadillo/plakoglobin/beta-catenin proteins present in Adhesive Junction complexes of higher eukaryotes. We discuss this similarity in connection with the observed pleiotropic effects of srp1 mutations.
Eric Wieschaus – One of the best experts on this subject based on the ideXlab platform.
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a role for the drosophila segment polarity gene armadillo in cell adhesion and cytoskeletal integrity during oogenesis
Development, 1993Co-Authors: Mark Peifer, Sandra Orsulic, Dari Sweeton, Eric WieschausAbstract:The epithelial sheet is a structural unit common to many tissues. Its organization appears to depend on the function of the multi-protein complexes that form adherens Junctions. Elegant cell biological experiments have provided support for hypotheses explaining the function of adherens Junctions and of their components. These systems, however, lack the ability to test function within an entire organism during development. The realization that the product of the Drosophila segment polarity gene armadillo is related to the vertebrate Adhesive Junction components plakoglobin and beta-catenin led to the suggestion that armadillo might provide a genetic handle to study Adhesive Junction structure and function. An examination of the potential function of Armadillo in cell-cell Adhesive Junctions was initiated using the Drosophila ovary as the model system. We examined the distribution of Armadillo in the Drosophila ovary and demonstrated that this localization often parallels the location of cell-cell Adhesive Junctions. The consequences of removing armadillo function from the germ-line cells of the ovary were also examined. Germ-line armadillo mutations appear to disrupt processes requiring cell adhesion and integrity of the actin cytoskeleton, consistent with a role for Armadillo in cell-cell Adhesive Junctions. We have also used armadillo mutations to examine the effects on ovarian development of altering the stereotyped cell arrangements of the ovary. The implications of these results for the role of Adhesive Junctions during development are discussed.
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the vertebrate Adhesive Junction proteins beta catenin and plakoglobin and the drosophila segment polarity gene armadillo form a multigene family with similar properties
Journal of Cell Biology, 1992Co-Authors: Mark Peifer, Eric Wieschaus, Pierre D Mccrea, Kathleen J Green, Barry M GumbinerAbstract:Three proteins identified by quite different criteria in three different systems, the Drosophila segment polarity gene armadillo, the human desmosomal protein plakoglobin, and the Xenopus E-cadherin-associated protein beta-catenin, share amino acid sequence similarity. These findings raise questions about the relationship among the three molecules and their roles in different cell-cell Adhesive Junctions. We have found that antibodies against the Drosophila segment polarity gene armadillo cross react with a conserved vertebrate protein. This protein is membrane associated, probably via its interaction with a cadherin-like molecule. This cross-reacting protein is the cadherin-associated protein beta-catenin. Using anti-armadillo and antiplakoglobin antibodies, it was shown that beta-catenin and plakoglobin are distinct molecules, which can coexist in the same cell type. Plakoglobin interacts with the desmosomal glycoprotein desmoglein I, and weakly with E-cadherin. Although beta-catenin interacts tightly with E-cadherin, it does not seem to be associated with either desmoglein I or with isolated desmosomes. Anti-armadillo antibodies have been further used to determine the intracellular localization of beta-catenin, and to examine its tissue distribution. The implications of these results for the structure and function of different cell-cell Adhesive Junctions are discussed.
Ryoji Yano – One of the best experts on this subject based on the ideXlab platform.
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yeast srp1p has homology to armadillo plakoglobin beta catenin and participates in apparently multiple nuclear functions including the maintenance of the nucleolar structure
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: Ryoji Yano, Melanie Oakes, Michelle M Tabb, Masayasu NomuraAbstract:Abstract SRP1, a suppressor of certain temperature-sensitive mutations in RNA polymerase I in Saccharomyces cerevisiae, encodes a protein that is associated with nuclear pores. By using a system of conditional SRP1 expression and by isolating temperature-sensitive srp1 mutants, we have demonstrated that Srp1p is essential for maintenance of the crescent-shaped nucleolar structure, RNA transcription, and the proper functions of microtubules as inferred from analysis of nuclear division/segregation and immunofluorescence microscopy of microtubules. Different mutant alleles showed significantly different phenotypes in relation to these apparently multiple functional roles of the protein. We have also found that eight imperfect 42-amino-acid tandem repeats present in Srp1p are similar to the 42-amino-acid repeats in armadillo/plakoglobin/beta-catenin proteins present in Adhesive Junction complexes of higher eukaryotes. We discuss this similarity in connection with the observed pleiotropic effects of srp1 mutations.
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Yeast Srp1p has homology to armadillo/plakoglobin/beta-catenin and participates in apparently multiple nuclear functions including the maintenance of the nucleolar structure
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: Ryoji Yano, Melanie Oakes, Michelle M Tabb, Masayasu NomuraAbstract:Abstract SRP1, a suppressor of certain temperature-sensitive mutations in RNA polymerase I in Saccharomyces cerevisiae, encodes a protein that is associated with nuclear pores. By using a system of conditional SRP1 expression and by isolating temperature-sensitive srp1 mutants, we have demonstrated that Srp1p is essential for maintenance of the crescent-shaped nucleolar structure, RNA transcription, and the proper functions of microtubules as inferred from analysis of nuclear division/segregation and immunofluorescence microscopy of microtubules. Different mutant alleles showed significantly different phenotypes in relation to these apparently multiple functional roles of the protein. We have also found that eight imperfect 42-amino-acid tandem repeats present in Srp1p are similar to the 42-amino-acid repeats in armadillo/plakoglobin/beta-catenin proteins present in Adhesive Junction complexes of higher eukaryotes. We discuss this similarity in connection with the observed pleiotropic effects of srp1 mutations.