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Jay T Groves - One of the best experts on this subject based on the ideXlab platform.

  • coupled membrane lipid miscibility and phosphotyrosine driven Protein condensation phase transitions
    Biophysical Journal, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the linker for activation of T cells (LAT):growth-factor-receptor-bound Protein 2 (Grb2):son of sevenless (SOS) Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that the assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate.

  • coupling between lipid miscibility and phosphotyrosine driven Protein condensation at the membrane
    bioRxiv, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Abstract Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the LAT:Grb2:SOS Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate. Statement of Significance Protein condensation phase transitions are emerging as an important organizing principles in cells. One such condensate plays a key role in T cell receptor signaling. Immediately after receptor activation, multivalent phosphorylation of the adaptor Protein LAT at the plasma membrane leads to networked assembly of a number of signaling Proteins into a two-dimensional condensate on the membrane surface. In this study, we demonstrate that LAT condensates in reconstituted vesicles are sufficient to drive lipid phase separation. This lipid reorganization drives another key downstream signaling molecule, Ras, into the LAT condensates. These results show that the LAT condensation phase transition, which is actively controlled by phosphorylation reactions, extends its influence to control lipid phase separation in the underlying membrane.

  • dynamic scaling analysis of molecular motion within the lat grb2 SOS Protein network on membranes
    Biophysical Journal, 2017
    Co-Authors: William Y C Huang, Hankuei Chiang, Jay T Groves
    Abstract:

    Abstract Biochemical signaling pathways often involve Proteins with multiple, modular interaction domains. Signaling activates binding sites, such as by tyrosine phosphorylation, which enables Protein recruitment and growth of networked Protein assemblies. Although widely observed, the physical properties of the assemblies, as well as the mechanisms by which they function, remain largely unknown. Here we examine molecular mobility within LAT:Grb2:SOS assemblies on supported membranes by single-molecule tracking. Trajectory analysis reveals a discrete temporal transition to subdiffusive motion below a characteristic timescale, indicating that the LAT:Grb2:SOS assembly has the dynamical structure of a loosely entangled polymer. Such dynamical analysis is also applicable in living cells, where it offers another dimension on the characteristics of cellular signaling assemblies.

William Y C Huang - One of the best experts on this subject based on the ideXlab platform.

  • coupled membrane lipid miscibility and phosphotyrosine driven Protein condensation phase transitions
    Biophysical Journal, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the linker for activation of T cells (LAT):growth-factor-receptor-bound Protein 2 (Grb2):son of sevenless (SOS) Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that the assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate.

  • coupling between lipid miscibility and phosphotyrosine driven Protein condensation at the membrane
    bioRxiv, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Abstract Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the LAT:Grb2:SOS Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate. Statement of Significance Protein condensation phase transitions are emerging as an important organizing principles in cells. One such condensate plays a key role in T cell receptor signaling. Immediately after receptor activation, multivalent phosphorylation of the adaptor Protein LAT at the plasma membrane leads to networked assembly of a number of signaling Proteins into a two-dimensional condensate on the membrane surface. In this study, we demonstrate that LAT condensates in reconstituted vesicles are sufficient to drive lipid phase separation. This lipid reorganization drives another key downstream signaling molecule, Ras, into the LAT condensates. These results show that the LAT condensation phase transition, which is actively controlled by phosphorylation reactions, extends its influence to control lipid phase separation in the underlying membrane.

  • dynamic scaling analysis of molecular motion within the lat grb2 SOS Protein network on membranes
    Biophysical Journal, 2017
    Co-Authors: William Y C Huang, Hankuei Chiang, Jay T Groves
    Abstract:

    Abstract Biochemical signaling pathways often involve Proteins with multiple, modular interaction domains. Signaling activates binding sites, such as by tyrosine phosphorylation, which enables Protein recruitment and growth of networked Protein assemblies. Although widely observed, the physical properties of the assemblies, as well as the mechanisms by which they function, remain largely unknown. Here we examine molecular mobility within LAT:Grb2:SOS assemblies on supported membranes by single-molecule tracking. Trajectory analysis reveals a discrete temporal transition to subdiffusive motion below a characteristic timescale, indicating that the LAT:Grb2:SOS assembly has the dynamical structure of a loosely entangled polymer. Such dynamical analysis is also applicable in living cells, where it offers another dimension on the characteristics of cellular signaling assemblies.

Jean K Chung - One of the best experts on this subject based on the ideXlab platform.

  • coupled membrane lipid miscibility and phosphotyrosine driven Protein condensation phase transitions
    Biophysical Journal, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the linker for activation of T cells (LAT):growth-factor-receptor-bound Protein 2 (Grb2):son of sevenless (SOS) Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that the assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate.

  • coupling between lipid miscibility and phosphotyrosine driven Protein condensation at the membrane
    bioRxiv, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Abstract Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the LAT:Grb2:SOS Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate. Statement of Significance Protein condensation phase transitions are emerging as an important organizing principles in cells. One such condensate plays a key role in T cell receptor signaling. Immediately after receptor activation, multivalent phosphorylation of the adaptor Protein LAT at the plasma membrane leads to networked assembly of a number of signaling Proteins into a two-dimensional condensate on the membrane surface. In this study, we demonstrate that LAT condensates in reconstituted vesicles are sufficient to drive lipid phase separation. This lipid reorganization drives another key downstream signaling molecule, Ras, into the LAT condensates. These results show that the LAT condensation phase transition, which is actively controlled by phosphorylation reactions, extends its influence to control lipid phase separation in the underlying membrane.

Christiaan Michiels - One of the best experts on this subject based on the ideXlab platform.

  • SulA-dependent hypersensitivity to high pressure and hyperfilamentation after high-pressure treatment of Escherichia coli lon mutants.
    Research in microbiology, 2004
    Co-Authors: Abram Aertsen, Christiaan Michiels
    Abstract:

    Abstract High-pressure treatment ( > 100 MPa ) is known to induce several heat shock Proteins as well as an SOS response in Escherichia coli . In the current work, we have investigated properties with respect to high-pressure treatment of mutants-deficient in Lon, a pressure-induced ATP-dependent protease that belongs to the heat shock regulon but that also has a link to the SOS regulon. We report that lon mutants show increased pressure sensitivity and exhibit hyperfilamentation during growth after high-pressure treatment. Both phenotypes could be entirely attributed to the action of the SOS Protein SulA, a potent inhibitor of the cell division ring Protein FtsZ and a specific target of the Lon protease, since they were suppressed by knock-out of SulA. Introduction of the lexA1 allele, which effectively blocks the entire SOS response, also suppressed the high pressure hypersensitivity of lon mutants, but not their UV hypersensitivity. These results indicate the existence of a SulA-dependent pathway of high-pressure-induced cell filamentation, and suggest involvement of the SOS response, and particularly of SulA, in high-pressure-mediated cell death in E. coli strains which are compromised in Lon function.

Ronald D Vale - One of the best experts on this subject based on the ideXlab platform.

  • coupled membrane lipid miscibility and phosphotyrosine driven Protein condensation phase transitions
    Biophysical Journal, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the linker for activation of T cells (LAT):growth-factor-receptor-bound Protein 2 (Grb2):son of sevenless (SOS) Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that the assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate.

  • coupling between lipid miscibility and phosphotyrosine driven Protein condensation at the membrane
    bioRxiv, 2020
    Co-Authors: Jean K Chung, William Y C Huang, Catherine B Carbone, Laura M Nocka, Atul N Parikh, Ronald D Vale, Jay T Groves
    Abstract:

    Abstract Lipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, Protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the LAT:Grb2:SOS Protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that assembly of the Protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS Protein condensate. Statement of Significance Protein condensation phase transitions are emerging as an important organizing principles in cells. One such condensate plays a key role in T cell receptor signaling. Immediately after receptor activation, multivalent phosphorylation of the adaptor Protein LAT at the plasma membrane leads to networked assembly of a number of signaling Proteins into a two-dimensional condensate on the membrane surface. In this study, we demonstrate that LAT condensates in reconstituted vesicles are sufficient to drive lipid phase separation. This lipid reorganization drives another key downstream signaling molecule, Ras, into the LAT condensates. These results show that the LAT condensation phase transition, which is actively controlled by phosphorylation reactions, extends its influence to control lipid phase separation in the underlying membrane.