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Richard N. Trelease - One of the best experts on this subject based on the ideXlab platform.
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The ER-Peroxisome connection in plants: Development of the “ER semi-autonomous Peroxisome maturation and replication” model for plant Peroxisome biogenesis
Biochimica et Biophysica Acta, 2006Co-Authors: Robert T. Mullen, Richard N. TreleaseAbstract:Abstract The perceived role of the ER in the biogenesis of plant Peroxisomes has evolved significantly from the original “ER vesiculation” model, which portrayed co-translational import of proteins into Peroxisomes originating from the ER, to the “ER semi-autonomous Peroxisome” model wherein membrane lipids and post-translationally acquired peroxisomal membrane proteins (PMPs) were derived from the ER. Results from more recent studies of various plant PMPs including ascorbate peroxidase, PEX10 and PEX16, as well as a viral replication protein, have since led to the formulation of a more elaborate “ER semi-autonomous Peroxisome maturation and replication” model. Herein we review these results in the context of this newly proposed model and its predecessor models. We discuss also key distinct features of the new model pertaining to its central premise that the ER defines the semi-autonomous maturation (maintenance/assembly/differentiation) and duplication (division) features of specialized classes of pre-existing plant Peroxisomes. This model also includes a novel Peroxisome-to-ER retrograde sorting pathway that may serve as a constitutive protein retrieval/regulatory system. In addition, new plant Peroxisomes are envisaged to arise primarily by duplication of the pre-existing Peroxisomes that receive essential membrane components from the ER.
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The ER-Peroxisome connection in plants: Development of the "ER semi-autonomous Peroxisome maturation and replication" model for plant Peroxisome biogenesis
Biochimica et Biophysica Acta - Molecular Cell Research, 2006Co-Authors: Robert T. Mullen, Richard N. TreleaseAbstract:The perceived role of the ER in the biogenesis of plant Peroxisomes has evolved significantly from the original "ER vesiculation" model, which portrayed co-translational import of proteins into Peroxisomes originating from the ER, to the "ER semi-autonomous Peroxisome" model wherein membrane lipids and post-translationally acquired peroxisomal membrane proteins (PMPs) were derived from the ER. Results from more recent studies of various plant PMPs including ascorbate peroxidase, PEX10 and PEX16, as well as a viral replication protein, have since led to the formulation of a more elaborate "ER semi-autonomous Peroxisome maturation and replication" model. Herein we review these results in the context of this newly proposed model and its predecessor models. We discuss also key distinct features of the new model pertaining to its central premise that the ER defines the semi-autonomous maturation (maintenance/assembly/differentiation) and duplication (division) features of specialized classes of pre-existing plant Peroxisomes. This model also includes a novel Peroxisome-to-ER retrograde sorting pathway that may serve as a constitutive protein retrieval/regulatory system. In addition, new plant Peroxisomes are envisaged to arise primarily by duplication of the pre-existing Peroxisomes that receive essential membrane components from the ER. © 2006 Elsevier B.V. All rights reserved.
Richard A. Rachubinski - One of the best experts on this subject based on the ideXlab platform.
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Peroxins Pex30 and Pex29 Dynamically Associate with Reticulons to Regulate Peroxisome Biogenesis from the Endoplasmic Reticulum
Journal of Biological Chemistry, 2016Co-Authors: Fred D Mast, Richard A. Rachubinski, Arvind P. Jamakhandi, Ramsey A. Saleem, David J. Dilworth, Richard S. Rogers, John D. AitchisonAbstract:Peroxisome proliferation occurs by at least two routes, division of existing Peroxisomes and de novo biogenesis from the endoplasmic reticulum (ER). The proteins and molecular mechanisms governing Peroxisome emergence from the ER are poorly characterized. In this study, we report that two integral membrane peroxins (proteins required for Peroxisome biogenesis) in Saccharomyces cerevisiae, Pex29 and Pex30, reside in distinct regions of the ER and associate with Rtn1 and Yop1, reticulon family members that contribute to ER morphology, to govern Peroxisome emergence from the ER. In vivo and in vitro analyses reveal that Peroxisome proliferation is therefore not restricted to the Peroxisome but begins at the level of the ER.
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Signaling dynamics and Peroxisomes
Current Opinion in Cell Biology, 2015Co-Authors: Fred D Mast, Richard A. Rachubinski, John D. AitchisonAbstract:Peroxisomes are remarkably responsive organelles. Their composition, abundance and even their mechanism of biogenesis are influenced strongly by cell type and the environment. This plasticity underlies peroxisomal functions in metabolism and the detoxification of dangerous reactive oxygen species. However, Peroxisomes are integrated into the cellular system as a whole such that they communicate intimately with other organelles, control signaling dynamics as in the case of innate immune responses to infectious disease, and contribute to processes as fundamental as longevity. The increasing evidence for Peroxisomes having roles in various cellular and organismal functions, combined with their malleability, suggests complex mechanisms operate to control cellular dynamics and the specificity of cellular responses and functions extending well beyond the Peroxisome itself. A deeper understanding of the functions of Peroxisomes and the mechanisms that control their plasticity could offer opportunities for exploiting changes in Peroxisome abundance to control cellular function.
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An ER-Peroxisome tether exerts Peroxisome population control in yeast.
The EMBO Journal, 2013Co-Authors: Barbara Knoblach, Nicolas Coquelle, Andrei Fagarasanu, Richard L Poirier, Richard A. RachubinskiAbstract:Eukaryotic cells compartmentalize biochemical reactions into membrane‐enclosed organelles that must be faithfully propagated from one cell generation to the next. Transport and retention processes balance the partitioning of organelles between mother and daughter cells. Here we report the identification of an ER‐Peroxisome tether that links Peroxisomes to the ER and ensures Peroxisome population control in the yeast Saccharomyces cerevisiae . The tether consists of the Peroxisome biogenic protein, Pex3p, and the Peroxisome inheritance factor, Inp1p. Inp1p bridges the two compartments by acting as a molecular hinge between ER‐bound Pex3p and peroxisomal Pex3p. Asymmetric Peroxisome division leads to the formation of Inp1p‐containing anchored Peroxisomes and Inp1p‐deficient mobile Peroxisomes that segregate to the bud. While Peroxisomes in mother cells are not released from tethering, de novo formation of tethers in the bud assists in the directionality of Peroxisome transfer. Peroxisomes are thus stably maintained over generations of cells through their continued interaction with tethers.
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Phosphorylation-dependent activation of Peroxisome proliferator protein PEX11 controls Peroxisome abundance
Journal of Biological Chemistry, 2009Co-Authors: Barbara Knoblach, Richard A. RachubinskiAbstract:Peroxisomes are dynamic organelles that divide continuously in growing cell cultures and expand extensively in lipid-rich medium. Peroxisome population control is achieved in part by Pex11p-dependent regulation of Peroxisome size and number. Although the production of Pex11p in yeast is tightly linked to Peroxisome biogenesis by transcriptional regulation of the PEX11 gene, it remains unclear if and how Pex11p activity could be modulated by rapid signaling. We report the reversible phosphorylation of Saccharomyces cerevisiae Pex11p in response to nutritional cues and delineate a mechanism for phosphorylation-dependent activation of Pex11p through the analysis of phosphomimicking mutants. Peroxisomal phenotypes in the PEX11-A and PEX11-D strains expressing constitutively dephosphorylated and phosphorylated forms of Pex11p resemble those of PEX11 gene knock-out and overexpression mutants, although PEX11 transcript and Pex11 protein levels remain unchanged. We demonstrate functional inequality and differences in subcellular localization of the Pex11p forms. Pex11Dp promotes Peroxisome fragmentation when reexpressed in cells containing induced Peroxisomes. Pex11p translocates between endoplasmic reticulum and Peroxisomes in a phosphorylation-dependent manner, whereas Pex11Ap and Pex11Dp are impaired in trafficking and constitutively associated with mature and proliferating Peroxisomes, respectively. Overexpression of cyclin-dependent kinase Pho85p results in hyperphosphorylation of Pex11p and Peroxisome proliferation. This study provides the first evidence for control of Peroxisome dynamics by phosphorylation-dependent regulation of a peroxin.
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pex3 Peroxisome biogenesis proteins function in Peroxisome inheritance as class v myosin receptors
Journal of Cell Biology, 2009Co-Authors: Jinlan Chang, Andrei Fagarasanu, Fred D Mast, Dorian A Rachubinski, Gary Eitzen, Joel B Dacks, Richard A. RachubinskiAbstract:In Saccharomyces cerevisiae, peroxisomal inheritance from mother cell to bud is conducted by the class V myosin motor, Myo2p. However, homologues of S. cerevisiae Myo2p peroxisomal receptor, Inp2p, are not readily identifiable outside the Saccharomycetaceae family. Here, we demonstrate an unexpected role for Pex3 proteins in Peroxisome inheritance. Both Pex3p and Pex3Bp are peroxisomal integral membrane proteins that function as peroxisomal receptors for class V myosin through direct interaction with the myosin globular tail. In cells lacking Pex3Bp, Peroxisomes are preferentially retained by the mother cell, whereas most Peroxisomes gather and are transferred en masse to the bud in cells overexpressing Pex3Bp or Pex3p. Our results reveal an unprecedented role for members of the Pex3 protein family in Peroxisome motility and inheritance in addition to their well-established role in Peroxisome biogenesis at the endoplasmic reticulum. Our results point to a temporal link between Peroxisome formation and inheritance and delineate a general mechanism of Peroxisome inheritance in eukaryotic cells.
Suresh Subramani - One of the best experts on this subject based on the ideXlab platform.
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peroxisomal pex3 activates selective autophagy of Peroxisomes via interaction with the pexophagy receptor atg30
Journal of Biological Chemistry, 2015Co-Authors: Sarah F Burnett, Jeanclaude Farre, Taras Y Nazarko, Suresh SubramaniAbstract:Abstract Pexophagy is a process that selectively degrades Peroxisomes by autophagy. The Pichia pastoris pexophagy receptor Atg30 is recruited to Peroxisomes under Peroxisome proliferation conditions. During pexophagy, Atg30 undergoes phosphorylation, a prerequisite for its interactions with the autophagy scaffold protein Atg11 and the ubiquitin-like protein Atg8. Atg30 is subsequently shuttled to the vacuole along with the targeted Peroxisome for degradation. Here, we defined the binding site for Atg30 on the peroxisomal membrane protein Pex3 and uncovered a role for Pex3 in the activation of Atg30 via phosphorylation and in the recruitment of Atg11 to the receptor protein complex. Pex3 is classically a docking protein for other proteins that affect Peroxisome biogenesis, division, and segregation. We conclude that Pex3 has a role beyond simple docking of Atg30 and that its interaction with Atg30 regulates pexophagy in the yeast P. pastoris.
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ppatg30 tags Peroxisomes for turnover by selective autophagy
Developmental Cell, 2008Co-Authors: Jeanclaude Farre, Ravi Manjithaya, Richard D Mathewson, Suresh SubramaniAbstract:Autophagy, an intrinsically nonselective process, can also target selective cargo for degradation. The mechanism of selective Peroxisome turnover by autophagy-related processes (pexophagy), termed micropexophagy and macropexophagy, is unknown. We show how a Pichia pastoris protein, PpAtg30, mediates Peroxisome selection during pexophagy. It is necessary for pexophagy, but not for other selective and nonselective autophagy-related processes. It localizes at the Peroxisome membrane via interaction with peroxins, and during pexophagy it colocalizes transiently at the preautophagosomal structure (PAS) and interacts with the autophagy machinery. PpAtg30 is required for formation of pexophagy intermediates, such as the micropexophagy apparatus (MIPA) and the pexophagosome (Ppg). During pexophagy, PpAtg30 undergoes multiple phosphorylations, at least one of which is required for pexophagy. PpAtg30 overexpression stimulates pexophagy even under Peroxisome-induction conditions, impairing Peroxisome biogenesis. Therefore, PpAtg30 is a key player in the selection of Peroxisomes as cargo and in their delivery to the autophagy machinery for pexophagy.
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Import of Proteins into Peroxisomes
Protein Targeting Transport and Translocation, 2008Co-Authors: Suresh Subramani, Vincent Dammai, Partha P. Hazra, Suriapranata IvetAbstract:Publisher Summary This chapter outlines the import of protein into Peroxisomes. The first section reveals the discovery and metabolic functions of Peroxisomes and highlights that Peroxisomes were the last of the major subcellular organelles to be discovered. Unlike the nucleus, mitochondrion and chloroplast, Peroxisomes have no DNA. Therefore, all of their polypeptide components are encoded by nuclear genes, synthesized on cytoplasmic polyribosomes, and then, transported post-translationally to Peroxisomes. Peroxisomal membrane proteins (PMPs) embedded in the organelle membrane use membrane PTSs (mPTSs) for their targeting. These have been characterized in several proteins but have little in common except for a basic region. Early experiments on the peroxisomal targeting of reporter and endogenous proteins in the late 1980s showed that similar PTSs were used from yeast to humans. The alternative model is one in which the PTS receptors recognize cargo in the cytosol and shuttle them to the Peroxisome. For the few PMPs whose targeting has been analyzed in vitro, the process is independent of ATE but dependent on cytosolic factors. For the few PMPs whose targeting has been analyzed in vitro, the process is independent of ATE but dependent on cytosolic factors. This chapter also highlights Peroxisome inheritance and biogenesis intermediates along with a brief note on disorders involving Peroxisomes.
Michael Schrader - One of the best experts on this subject based on the ideXlab platform.
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The Peroxisome: an update on mysteries 2.0
Histochemistry and Cell Biology, 2018Co-Authors: Markus Islinger, H. Dariush Fahimi, Alfred Voelkl, Michael SchraderAbstract:Peroxisomes are key metabolic organelles, which contribute to cellular lipid metabolism, e.g. the β-oxidation of fatty acids and the synthesis of myelin sheath lipids, as well as cellular redox balance. Peroxisomal dysfunction has been linked to severe metabolic disorders in man, but Peroxisomes are now also recognized as protective organelles with a wider significance in human health and potential impact on a large number of globally important human diseases such as neurodegeneration, obesity, cancer, and age-related disorders. Therefore, the interest in Peroxisomes and their physiological functions has significantly increased in recent years. In this review, we intend to highlight recent discoveries, advancements and trends in Peroxisome research, and present an update as well as a continuation of two former review articles addressing the unsolved mysteries of this astonishing organelle. We summarize novel findings on the biological functions of Peroxisomes, their biogenesis, formation, membrane dynamics and division, as well as on Peroxisome–organelle contacts and cooperation. Furthermore, novel peroxisomal proteins and machineries at the peroxisomal membrane are discussed. Finally, we address recent findings on the role of Peroxisomes in the brain, in neurological disorders, and in the development of cancer.
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Peroxisome Morphology in Pathologies
Histology and Histopathology, 2014Co-Authors: Michael Schrader, Inês G. Castro, H. Dariush Fahimi, Markus IslingerAbstract:Peroxisomes are ubiquitous and heterogeneous multi-purpose organelles, which are indispensable for human health and development. The invention of specific cytochemical staining methods for Peroxisomes revealed their high plasticity and ability to alter their morphology in response to environmental cues. Peroxisome dynamics depend on peroxisomal morphology proteins such as Pex11p, DLP1/Drp1, Fis1, Mff, and GDAP1 which are partially shared with mitochondria. Here, we address variations of Peroxisome morphology in the healthy organism and summarize findings on altered organelle morphology in peroxisomal disorders. We highlight recent insights in novel disorders with defects in Peroxisome morphology proteins and alterations of Peroxisomes during stress and signaling, as well as secondary alterations in liver disease and cancer.
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The Peroxisome: an update on mysteries
Histochemistry and Cell Biology, 2012Co-Authors: Markus Islinger, H. Dariush Fahimi, Sandra Grille, Michael SchraderAbstract:Peroxisomes contribute to several crucial metabolic processes such as β-oxidation of fatty acids, biosynthesis of ether phospholipids and metabolism of reactive oxygen species, which render them indispensable to human health and development. Peroxisomes are highly dynamic organelles that rapidly assemble, multiply and degrade in response to metabolic needs. In recent years, the interest in Peroxisomes and their physiological functions has significantly increased. This review intends to highlight recent discoveries and trends in Peroxisome research, and represents an update as well as a continuation of a former review article. Novel exciting findings on the biological functions, biogenesis, formation and degradation of Peroxisomes, on peroxisomal dynamics and division, as well as on the interaction and cross-talk of Peroxisomes with other subcellular compartments are addressed. Furthermore, recent findings on the role of Peroxisomes in the brain are discussed.
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The Peroxisome: an update on mysteries 2.0.
Histochemistry and Cell Biology, 2012Co-Authors: Markus Islinger, H. Dariush Fahimi, Sandra Grille, Michael SchraderAbstract:Peroxisomes contribute to several crucial metabolic processes such as β-oxidation of fatty acids, biosynthesis of ether phospholipids and metabolism of reactive oxygen species, which render them indispensable to human health and development. Peroxisomes are highly dynamic organelles that rapidly assemble, multiply and degrade in response to metabolic needs. In recent years, the interest in Peroxisomes and their physiological functions has significantly increased. This review intends to highlight recent discoveries and trends in Peroxisome research, and represents an update as well as a continuation of a former review article. Novel exciting findings on the biological functions, biogenesis, formation and degradation of Peroxisomes, on peroxisomal dynamics and division, as well as on the interaction and cross-talk of Peroxisomes with other subcellular compartments are addressed. Furthermore, recent findings on the role of Peroxisomes in the brain are discussed.
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Fission and proliferation of Peroxisomes.
Biochimica et Biophysica Acta, 2011Co-Authors: Michael Schrader, Nina A. Bonekamp, Markus IslingerAbstract:Abstract Peroxisomes are remarkably dynamic, multifunctional organelles, which react to physiological changes in their cellular environment and adopt their morphology, number, enzyme content and metabolic functions accordingly. At the organelle level, the key molecular machinery controlling peroxisomal membrane elongation and remodeling as well as membrane fission is becoming increasingly established and defined. Key players in Peroxisome division are conserved in animals, plants and fungi, and key fission components are shared with mitochondria. However, the physiological stimuli and corresponding signal transduction pathways regulating and modulating Peroxisome maintenance and proliferation are, despite a few exceptions, largely unexplored. There is emerging evidence that peroxisomal dynamics and proper regulation of Peroxisome number and morphology are crucial for the physiology of the cell, as well as for the pathology of the organism. Here, we discuss several key aspects of peroxisomal fission and proliferation and highlight their association with certain diseases. We address signaling and transcriptional events resulting in Peroxisome proliferation, and focus on novel findings concerning the key division components and their interplay. Finally, we present an updated model of peroxisomal growth and division. This article is part of a Special Issue entitled: Metabolic Functions and Biogenesis of Peroxisomes in Health and Disease.
Robert T. Mullen - One of the best experts on this subject based on the ideXlab platform.
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The ER-Peroxisome connection in plants: Development of the “ER semi-autonomous Peroxisome maturation and replication” model for plant Peroxisome biogenesis
Biochimica et Biophysica Acta, 2006Co-Authors: Robert T. Mullen, Richard N. TreleaseAbstract:Abstract The perceived role of the ER in the biogenesis of plant Peroxisomes has evolved significantly from the original “ER vesiculation” model, which portrayed co-translational import of proteins into Peroxisomes originating from the ER, to the “ER semi-autonomous Peroxisome” model wherein membrane lipids and post-translationally acquired peroxisomal membrane proteins (PMPs) were derived from the ER. Results from more recent studies of various plant PMPs including ascorbate peroxidase, PEX10 and PEX16, as well as a viral replication protein, have since led to the formulation of a more elaborate “ER semi-autonomous Peroxisome maturation and replication” model. Herein we review these results in the context of this newly proposed model and its predecessor models. We discuss also key distinct features of the new model pertaining to its central premise that the ER defines the semi-autonomous maturation (maintenance/assembly/differentiation) and duplication (division) features of specialized classes of pre-existing plant Peroxisomes. This model also includes a novel Peroxisome-to-ER retrograde sorting pathway that may serve as a constitutive protein retrieval/regulatory system. In addition, new plant Peroxisomes are envisaged to arise primarily by duplication of the pre-existing Peroxisomes that receive essential membrane components from the ER.
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The ER-Peroxisome connection in plants: Development of the "ER semi-autonomous Peroxisome maturation and replication" model for plant Peroxisome biogenesis
Biochimica et Biophysica Acta - Molecular Cell Research, 2006Co-Authors: Robert T. Mullen, Richard N. TreleaseAbstract:The perceived role of the ER in the biogenesis of plant Peroxisomes has evolved significantly from the original "ER vesiculation" model, which portrayed co-translational import of proteins into Peroxisomes originating from the ER, to the "ER semi-autonomous Peroxisome" model wherein membrane lipids and post-translationally acquired peroxisomal membrane proteins (PMPs) were derived from the ER. Results from more recent studies of various plant PMPs including ascorbate peroxidase, PEX10 and PEX16, as well as a viral replication protein, have since led to the formulation of a more elaborate "ER semi-autonomous Peroxisome maturation and replication" model. Herein we review these results in the context of this newly proposed model and its predecessor models. We discuss also key distinct features of the new model pertaining to its central premise that the ER defines the semi-autonomous maturation (maintenance/assembly/differentiation) and duplication (division) features of specialized classes of pre-existing plant Peroxisomes. This model also includes a novel Peroxisome-to-ER retrograde sorting pathway that may serve as a constitutive protein retrieval/regulatory system. In addition, new plant Peroxisomes are envisaged to arise primarily by duplication of the pre-existing Peroxisomes that receive essential membrane components from the ER. © 2006 Elsevier B.V. All rights reserved.
