The Experts below are selected from a list of 1794 Experts worldwide ranked by ideXlab platform
Kirankumar S. Mysore - One of the best experts on this subject based on the ideXlab platform.
-
symbiotic root infections in medicago truncatula require remorin mediated receptor stabilization in membrane Nanodomains
Proceedings of the National Academy of Sciences of the United States of America, 2018Co-Authors: Pengbo Liang, Thomas F Stratil, Claudia Popp, Macarena Marin, Jessica Folgmann, Kirankumar S. MysoreAbstract:Plant cell infection is tightly controlled by cell surface receptor-like kinases (RLKs). Like other RLKs, the Medicago truncatula entry receptor LYK3 laterally segregates into membrane Nanodomains in a stimulus-dependent manner. Although Nanodomain localization arises as a generic feature of plant membrane proteins, the molecular mechanisms underlying such dynamic transitions and their functional relevance have remained poorly understood. Here we demonstrate that actin and the flotillin protein FLOT4 form the primary and indispensable core of a specific Nanodomain. Infection-dependent induction of the remorin protein and secondary molecular scaffold SYMREM1 results in subsequent recruitment of ligand-activated LYK3 and its stabilization within these membrane subcompartments. Reciprocally, the majority of this LYK3 receptor pool is destabilized at the plasma membrane and undergoes rapid endocytosis in symrem1 mutants on rhizobial inoculation, resulting in premature abortion of host cell infections. These data reveal that receptor recruitment into Nanodomains is indispensable for their function during host cell infection.
-
symbiotic root infections in medicago truncatula require remorin mediated receptor stabilization in membrane Nanodomains
bioRxiv, 2017Co-Authors: Pengbo Liang, Thomas F Stratil, Claudia Popp, Macarena Marin, Jessica Folgmann, Kirankumar S. MysoreAbstract:Plant cell infection is tightly controlled by cell surface receptor-like kinases (RLKs) Alike other RLKs the Medicago truncatula entry receptor LYK3 laterally segregates into membrane Nanodomains in a stimulus-dependent manner. Although Nanodomain localization arises as a generic feature of plant membrane proteins, molecular mechanisms underlying such dynamic transitions and their functional relevance remained poorly understood. Here, we demonstrate that actin and the flotillin protein FLOT4 form the primary and indispensable core of a specific Nanodomain. Infection-dependent induction of the remorin protein and secondary molecular scaffold SYMREM1 results in subsequent recruitment of ligand-activated LYK3 and its stabilization within these membrane subcompartments. Reciprocally, the majority of this LYK3 receptor pool is destabilized at the plasma membrane and undergoes rapid endocytosis in symrem1 mutants upon rhizobial inoculation resulting in premature abortion of host cell infections. These data reveal that receptor recruitment into Nanodomains is indispensable for their function during host cell infection.
Isuru D Jayasinghe - One of the best experts on this subject based on the ideXlab platform.
-
true molecular scale visualization of variable clustering properties of ryanodine receptors
Cell Reports, 2018Co-Authors: David Baddeley, Alexander H Clowsley, Carl Harrison, E M Green, Lorenzo Di Michele, Isuru D Jayasinghe, Tobias Lutz, Christian SoellerAbstract:Summary Signaling Nanodomains rely on spatial organization of proteins to allow controlled intracellular signaling. Examples include calcium release sites of cardiomyocytes where ryanodine receptors (RyRs) are clustered with their molecular partners. Localization microscopy has been crucial to visualizing these Nanodomains but has been limited by brightness of markers, restricting the resolution and quantification of individual proteins clustered within. Harnessing the remarkable localization precision of DNA-PAINT (
-
true molecular scale visualization of variable clustering properties of ryanodine receptors
Cell Reports, 2018Co-Authors: David Baddeley, Alexander H Clowsley, Carl Harrison, Lorenzo Di Michele, Isuru D Jayasinghe, Tobias Lutz, Ruisheng Lin, Ellen Green, Christian SoellerAbstract:Signaling Nanodomains rely on spatial organization of proteins to allow controlled intracellular signaling. Examples include calcium release sites of cardiomyocytes where ryanodine receptors (RyRs) are clustered with their molecular partners. Localization microscopy has been crucial to visualizing these Nanodomains but has been limited by brightness of markers, restricting the resolution and quantification of individual proteins clustered within. Harnessing the remarkable localization precision of DNA-PAINT (<10 nm), we visualized punctate labeling within these Nanodomains, confirmed as single RyRs. RyR positions within sub-plasmalemmal Nanodomains revealed how they are organized randomly into irregular clustering patterns leaving significant gaps occupied by accessory or regulatory proteins. RyR-inhibiting protein junctophilin-2 appeared highly concentrated adjacent to RyR channels. Analyzing these molecular maps showed significant variations in the co-clustering stoichiometry between junctophilin-2 and RyR, even between nearby Nanodomains. This constitutes an additional level of complexity in RyR arrangement and regulation of calcium signaling, intrinsically built into the Nanodomains.
Ivan Robert Nabi - One of the best experts on this subject based on the ideXlab platform.
-
reticulon and climp 63 regulate Nanodomain organization of peripheral er tubules
PLOS Biology, 2019Co-Authors: Ivan Robert NabiAbstract:The endoplasmic reticulum (ER) is an expansive, membrane-enclosed organelle composed of smooth peripheral tubules and rough, ribosome-studded central ER sheets whose morphology is determined, in part, by the ER-shaping proteins, reticulon (RTN) and cytoskeleton-linking membrane protein 63 (CLIMP-63), respectively. Here, stimulated emission depletion (STED) super-resolution microscopy shows that reticulon4a (RTN4a) and CLIMP-63 also regulate the organization and dynamics of peripheral ER tubule Nanodomains. STED imaging shows that lumenal ER monomeric oxidizing environment-optimized green fluorescent protein (ERmoxGFP), membrane Sec61βGFP, knock-in calreticulin-GFP, and antibody-labeled ER-resident proteins calnexin and derlin-1 are all localized to periodic puncta along the length of peripheral ER tubules that are not readily observable by diffraction limited confocal microscopy. RTN4a segregates away from and restricts lumenal blob length, while CLIMP-63 associates with and increases lumenal blob length. RTN4a and CLIMP-63 also regulate the Nanodomain distribution of ER-resident proteins, being required for the preferential segregation of calnexin and derlin-1 puncta away from lumenal ERmoxGFP blobs. High-speed (40 ms/frame) live cell STED imaging shows that RTN4a and CLIMP-63 regulate dynamic nanoscale lumenal compartmentalization along peripheral ER tubules. RTN4a enhances and CLIMP-63 disrupts the local accumulation of lumenal ERmoxGFP at spatially defined sites along ER tubules. The ER-shaping proteins RTN and CLIMP-63 therefore regulate lumenal ER Nanodomain heterogeneity, interaction with ER-resident proteins, and dynamics in peripheral ER tubules.
-
reticulon and climp 63 regulate Nanodomain organization of peripheral er tubules
bioRxiv, 2019Co-Authors: Ivan Robert NabiAbstract:The endoplasmic reticulum (ER) is an expansive, membrane-enclosed organelle composed of smooth peripheral tubules and rough, ribosome-studded central ER sheets whose morphology is determined, in part, by the ER-shaping proteins, reticulon and CLIMP-63, respectively. Here, STimulated Emission Depletion (STED) super-resolution microscopy shows that reticulon4a (RTN4a) and CLIMP-63 also regulate the organization and dynamics of peripheral ER tubule Nanodomains. STED imaging shows that lumenal ERmoxGFP, membrane Sec61betaGFP, knock-in calreticulin-GFP and antibody-labeled ER resident proteins calnexin and derlin-1 are all localized to periodic puncta along the length of peripheral ER tubules that are not readily observable by diffraction limited confocal microscopy. RTN4a segregates away from and restricts lumenal blob length while CLIMP-63 associates with and increases lumenal blob length. RTN4a and CLIMP-63 also regulate the Nanodomain distribution of ER resident proteins, being required for the preferential segregation of calnexin and derlin-1 puncta away from lumenal ERmoxGFP blobs. High-speed (40 ms/frame) live cell STED imaging shows that RTN4a and CLIMP-63 regulate dynamic nanoscale lumenal compartmentalization along peripheral ER tubules. RTN4a enhances and CLIMP-63 disrupts the local accumulation of lumenal ERmoxGFP at spatially defined sites along ER tubules. The ER shaping proteins reticulon and CLIMP-63 therefore regulate lumenal ER Nanodomain heterogeneity, interaction with ER resident proteins and dynamics in peripheral ER tubules.
-
Reticulon and CLIMP-63 regulate Nanodomain organization of peripheral ER tubules
2019Co-Authors: Guang Gao, Chengjia Zhu, Emma Liu, Ivan Robert NabiAbstract:Abstract The endoplasmic reticulum (ER) is an expansive, membrane-enclosed organelle composed of smooth peripheral tubules and rough, ribosome-studded central ER sheets whose morphology is determined, in part, by the ER-shaping proteins, reticulon and CLIMP-63, respectively. Here, STimulated Emission Depletion (STED) super-resolution microscopy shows that reticulon and CLIMP-63 also control the organization and dynamics of peripheral ER tubule Nanodomains. STED imaging shows that lumenal ERmoxGFP, membrane Sec61βGFP, knock-in calreticulin-GFP and antibody-labeled ER resident proteins calnexin and derlin-1 are all localized to periodic puncta along the length of peripheral ER tubules that are not readily observable by diffraction limited confocal microscopy. Reticulon segregates away from and restricts lumenal blob length while CLIMP-63 associates with and increases lumenal blob length. Reticulon and CLIMP-63 also regulate the Nanodomain distribution of ER resident proteins, being required for the preferential segregation of calnexin and derlin-1 puncta away from lumenal ERmoxGFP blobs. High-speed (40 ms/frame) live cell STED imaging shows that reticulon and CLIMP-63 control nanoscale compartmentalization of lumenal flow in peripheral ER tubules. Reticulon enhances and CLIMP-63 disrupts the local accumulation of lumenal ERmoxGFP at spatially defined sites along ER tubules. The ER shaping proteins reticulon and CLIMP-63 therefore control lumenal ER Nanodomain dynamics, heterogeneity and interaction with ER resident proteins in peripheral ER tubules.
J F Scott - One of the best experts on this subject based on the ideXlab platform.
-
electron beam driven relaxation oscillations in ferroelectric nanodisks
Applied Physics Letters, 2015Co-Authors: Rajeev Ahluwalia, Ashok Kumar, David J Srolovitz, Premala Chandra, J F ScottAbstract:Using a combination of computational simulations, atomic-scale resolution imaging and phenomenological modelling, we examine the underlying mechanism for Nanodomain restructuring in lead zirconate titanate nanodisks driven by electron beams. The observed subhertz Nanodomain dynamics are identified with relaxation oscillations where the charging/discharging cycle time is determined by saturation of charge traps and Nanodomain wall creep. These results are unusual in that they indicate very slow athermal dynamics in nanoscale systems, and possible applications of gated versions are discussed.
-
electron beam driven relaxation oscillations in ferroelectric nanodisks
arXiv: Materials Science, 2015Co-Authors: Rajeev Ahluwalia, Ashok Kumar, David J Srolovitz, Premala Chandra, J F ScottAbstract:Using a combination of computational simulations, atomic-scale resolution imaging and phenomenological modelling, we examine the underlying mechanism for Nanodomain restructuring in lead zirconate titanate (PZT) nanodisks driven by electron beams. The observed subhertz Nanodomain dynamics are identified with relaxation oscillations where the charging/discharging cycle time is determined by saturation of charge traps and Nanodomain wall creep. These results are unusual in that they indicate very slow athermal dynamics in nanoscale systems.
-
Nanodomain faceting in ferroelectrics
Journal of Physics: Condensed Matter, 2008Co-Authors: J F Scott, Alexei Gruverman, I Vrejoiu, Marin AlexeAbstract:We show that after long times (24 h), individual circular domains in 50 nm thick [001] epitaxial films of ferroelectric lead zirconate titanate (PZT) develop facets due to the crystalline anisotropy, e.g. along [100] directions. This appears to be a creep process (Tybell et al 2002 Phys. Rev. Lett. 89 097601; Paruch et al 2006 J. Appl. Phys. 100 051608) and was first seen in a nanoarray of 180° domains (Ganpule et al 2002 Phys. Rev. B 65 014101). The effect is independent of polarity and thus rules out any electronic dependence on different work functions for top and bottom electrodes. The phenomenon is interpreted instead as a mechanical relaxation due to highly inhomogeneous stress distributions on the nanodisks, assumed to have stress-free edges.
Christian Soeller - One of the best experts on this subject based on the ideXlab platform.
-
true molecular scale visualization of variable clustering properties of ryanodine receptors
Cell Reports, 2018Co-Authors: David Baddeley, Alexander H Clowsley, Carl Harrison, E M Green, Lorenzo Di Michele, Isuru D Jayasinghe, Tobias Lutz, Christian SoellerAbstract:Summary Signaling Nanodomains rely on spatial organization of proteins to allow controlled intracellular signaling. Examples include calcium release sites of cardiomyocytes where ryanodine receptors (RyRs) are clustered with their molecular partners. Localization microscopy has been crucial to visualizing these Nanodomains but has been limited by brightness of markers, restricting the resolution and quantification of individual proteins clustered within. Harnessing the remarkable localization precision of DNA-PAINT (
-
true molecular scale visualization of variable clustering properties of ryanodine receptors
Cell Reports, 2018Co-Authors: David Baddeley, Alexander H Clowsley, Carl Harrison, Lorenzo Di Michele, Isuru D Jayasinghe, Tobias Lutz, Ruisheng Lin, Ellen Green, Christian SoellerAbstract:Signaling Nanodomains rely on spatial organization of proteins to allow controlled intracellular signaling. Examples include calcium release sites of cardiomyocytes where ryanodine receptors (RyRs) are clustered with their molecular partners. Localization microscopy has been crucial to visualizing these Nanodomains but has been limited by brightness of markers, restricting the resolution and quantification of individual proteins clustered within. Harnessing the remarkable localization precision of DNA-PAINT (<10 nm), we visualized punctate labeling within these Nanodomains, confirmed as single RyRs. RyR positions within sub-plasmalemmal Nanodomains revealed how they are organized randomly into irregular clustering patterns leaving significant gaps occupied by accessory or regulatory proteins. RyR-inhibiting protein junctophilin-2 appeared highly concentrated adjacent to RyR channels. Analyzing these molecular maps showed significant variations in the co-clustering stoichiometry between junctophilin-2 and RyR, even between nearby Nanodomains. This constitutes an additional level of complexity in RyR arrangement and regulation of calcium signaling, intrinsically built into the Nanodomains.
