Peroxisomes

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 126294 Experts worldwide ranked by ideXlab platform

Robert T Mullen - One of the best experts on this subject based on the ideXlab platform.

Michael Schrader - One of the best experts on this subject based on the ideXlab platform.

  • Peroxisome morphology in pathology.
    Histology and histopathology, 2020
    Co-Authors: D Ribeiro, H. Dariush Fahimi, I Castro, Michael Schrader
    Abstract:

    Peroxisomes are remarkably dynamic and versatile organelles that are essential for human health and development. They respond to physiological changes in the cellular environment by adapting their morphology, number, enzyme content and metabolic functions accordingly. With the discovery of the first key peroxisomal morphology proteins, the investigation of peroxisomal shape, distribution and dynamics has become an exciting new field in cell biology and biomedical sciences because of its relation to organelle functionality and its impact on developmental and physiological processes. In this review, we summarize recent findings on peroxisome biology, dynamics and the modulation of peroxisome morphology, especially in mammals. Furthermore, we discuss the roles of peroxisome dynamics and morphology in cell pathology and present recent examples for alterations in peroxisome morphology under disease conditions. Besides defects in the peroxisomal morphology machinery, we also address peroxisome biogenesis disorders, alterations of peroxisome number during carcinogenesis and liver cirrhosis, and morphological alterations of Peroxisomes during viral infection.

  • The peroxisome: an update on mysteries 2.0
    Histochemistry and Cell Biology, 2018
    Co-Authors: Markus Islinger, H. Dariush Fahimi, Alfred Voelkl, Michael Schrader
    Abstract:

    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.

  • proliferation and fission of Peroxisomes an update
    Biochimica et Biophysica Acta, 2016
    Co-Authors: Joseph L Costello, Michael Schrader, Luis F Godinho, Afsoon S Azadi, Markus Islinger
    Abstract:

    Abstract In mammals, Peroxisomes perform crucial functions in cellular metabolism, signalling and viral defense which are essential to the health and viability of the organism. In order to achieve this functional versatility Peroxisomes dynamically respond to molecular cues triggered by changes in the cellular environment. Such changes elicit a corresponding response in Peroxisomes, which manifests itself as a change in peroxisome number, altered enzyme levels and adaptations to the peroxisomal structure. In mammals the generation of new Peroxisomes is a complex process which has clear analogies to mitochondria, with both sharing the same division machinery and undergoing a similar division process. How the regulation of this division process is integrated into the cell's response to different stimuli, the signalling pathways and factors involved, remains somewhat unclear. Here, we discuss the mechanism of peroxisomal fission, the contributions of the various division factors and examine the potential impact of post-translational modifications, such as phosphorylation, on the proliferation process. We also summarize the signalling process and highlight the most recent data linking signalling pathways with peroxisome proliferation. This article is part of a Special Issue entitled: Peroxisomes edited by Ralf Erdmann.

  • Peroxisome-mitochondria interplay and disease
    Journal of Inherited Metabolic Disease, 2015
    Co-Authors: Michael Schrader, Luis F Godinho, Joseph Costello, Markus Islinger
    Abstract:

    Peroxisomes and mitochondria are ubiquitous, highly dynamic organelles with an oxidative type of metabolism in eukaryotic cells. Over the years, substantial evidence has been provided that Peroxisomes and mitochondria exhibit a close functional interplay which impacts on human health and development. The so-called “peroxisome-mitochondria connection” includes metabolic cooperation in the degradation of fatty acids, a redox-sensitive relationship, an overlap in key components of the membrane fission machineries and cooperation in anti-viral signalling and defence. Furthermore, combined peroxisome-mitochondria disorders with defects in organelle division have been revealed. In this review, we present the latest progress in the emerging field of peroxisomal and mitochondrial interplay in mammals with a particular emphasis on cooperative fatty acid β-oxidation, redox interplay, organelle dynamics, cooperation in anti-viral signalling and the resulting implications for disease.

  • Peroxisome Morphology in Pathologies
    Histology and Histopathology, 2014
    Co-Authors: Michael Schrader, Inês G. Castro, H. Dariush Fahimi, Markus Islinger
    Abstract:

    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.

Richard A. Rachubinski - One of the best experts on this subject based on the ideXlab platform.

  • Peroxins Pex30 and Pex29 Dynamically Associate with Reticulons to Regulate Peroxisome Biogenesis from the Endoplasmic Reticulum
    Journal of Biological Chemistry, 2016
    Co-Authors: Fred D. Mast, Arvind P. Jamakhandi, Ramsey A. Saleem, David J. Dilworth, Richard S. Rogers, Richard A. Rachubinski, John D. Aitchison
    Abstract:

    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.

  • Signaling dynamics and Peroxisomes
    Current Opinion in Cell Biology, 2015
    Co-Authors: Fred D. Mast, Richard A. Rachubinski, John D. Aitchison
    Abstract:

    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.

  • An ER-peroxisome tether exerts peroxisome population control in yeast.
    The EMBO Journal, 2013
    Co-Authors: Barbara Knoblach, Nicolas Coquelle, Andrei Fagarasanu, Richard L Poirier, Richard A. Rachubinski
    Abstract:

    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.

  • Phosphorylation-dependent activation of peroxisome proliferator protein PEX11 controls peroxisome abundance
    Journal of Biological Chemistry, 2009
    Co-Authors: Barbara Knoblach, Richard A. Rachubinski
    Abstract:

    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.

  • pex3 peroxisome biogenesis proteins function in peroxisome inheritance as class v myosin receptors
    Journal of Cell Biology, 2009
    Co-Authors: Jinlan Chang, Andrei Fagarasanu, Dorian A Rachubinski, Gary Eitzen, Fred D. Mast, Joel B. Dacks, Richard A. Rachubinski
    Abstract:

    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.

  • autophagic degradation of Peroxisomes in mammals
    Biochemical Society Transactions, 2016
    Co-Authors: Katarzyna Zientararytter, Suresh Subramani
    Abstract:

    Peroxisomes are essential organelles required for proper cell function in all eukaryotic organisms. They participate in a wide range of cellular processes including the metabolism of lipids and generation, as well as detoxification, of hydrogen peroxide (H2O2). Therefore, peroxisome homoeostasis, manifested by the precise and efficient control of peroxisome number and functionality, must be tightly regulated in response to environmental changes. Due to the existence of many physiological disorders and diseases associated with peroxisome homoeostasis imbalance, the dynamics of Peroxisomes have been widely examined. The increasing volume of reports demonstrating significant involvement of the autophagy machinery in peroxisome removal leads us to summarize current knowledge of peroxisome degradation in mammalian cells. In this review we present current models of peroxisome degradation. We particularly focus on pexophagy–the selective clearance of Peroxisomes through autophagy. We also critically discuss concepts of peroxisome recognition for pexophagy, including signalling and selectivity factors. Finally, we present examples of the pathological effects of pexophagy dysfunction and suggest promising future directions. * AMPK, : AMP-activated protein kinase; ATM, : Ataxia-telangiectasia mutated; CMA, : chaperone-mediated autophagy; EGFP, : enhanced green fluorescent protein; HIF-2α, : hypoxia-inducible factor 2α; 15-LOX, : 15-lipoxygenase; mTORC1, : mammalian target of rapamycin complex 1; PAS, : preautophagosomal structure; PIP, : phosphatidylinositol-phosphate; PTS, : peroxisome targeting signal; ROS, : reactive oxygen species; RPC, : receptor protein complex; TSC, : tuberous sclerosis complex; UBA, : ubiquitin-associated; ULK1, : unc51-like protein kinase 1

  • peroxisomal pex3 activates selective autophagy of Peroxisomes via interaction with the pexophagy receptor atg30
    Journal of Biological Chemistry, 2015
    Co-Authors: Sarah F Burnett, Jeanclaude Farre, Taras Y Nazarko, Suresh Subramani
    Abstract:

    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.

  • pexophagy the selective degradation of Peroxisomes
    International Journal of Cell Biology, 2012
    Co-Authors: Andreas Till, Sarah F Burnett, Ronak Lakhani, Suresh Subramani
    Abstract:

    Peroxisomes are single-membrane-bounded organelles present in the majority of eukaryotic cells. Despite the existence of great diversity among different species, cell types, and under different environmental conditions, Peroxisomes contain enzymes involved in β-oxidation of fatty acids and the generation, as well as detoxification, of hydrogen peroxide. The exigency of all eukaryotic cells to quickly adapt to different environmental factors requires the ability to precisely and efficiently control peroxisome number and functionality. Peroxisome homeostasis is achieved by the counterbalance between organelle biogenesis and degradation. The selective degradation of superfluous or damaged Peroxisomes is facilitated by several tightly regulated pathways. The most prominent peroxisome degradation system uses components of the general autophagy core machinery and is therefore referred to as “pexophagy.” In this paper we focus on recent developments in pexophagy and provide an overview of current knowledge and future challenges in the field. We compare different modes of pexophagy and mention shared and distinct features of pexophagy in yeast model systems, mammalian cells, and other organisms.

  • Import of Proteins into Peroxisomes
    Protein Targeting Transport and Translocation, 2008
    Co-Authors: Suresh Subramani, Vincent Dammai, Partha P. Hazra, Suriapranata Ivet
    Abstract:

    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.

  • protein import into Peroxisomes and biogenesis of the organelle
    Annual Review of Cell Biology, 1993
    Co-Authors: Suresh Subramani
    Abstract:

    INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446 FUNCTIONS OF Peroxisomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . ' 447 HUMAN PEROXISOMAL DISORDERS . . . . . . . . . . . . . . . . . . . . . . . . . . . 449 Peroxisomes AS A MODEL FOR ORGANELLE ASSEMBLY AND DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 1 Peroxisome Import and Assembly Mutants . . . . . . . . . . . . . . . . . . . . . . . . 451 PROTEIN IMPORT INTO Peroxisomes . . . . . . . . . . . . . . . . . . . . . . . . . 454 Targeting of Matrix Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 Conservation of the PTSI Tripeptide Variants . . . . . . . . . . . . . . . . . . . . . . 457 An Amino-Terminal PTS . . . . .. . . . . . . . . . . . .. . . .. . ... . . . . . . . . 458 Other Peroxisomal Matrix Targeting Signals . . . . . . . . . . . . . . . . . . . . . . . 459 Evolutionary Use of Diff erent PTSs by the Same Protein . . . . . . . . . . . . . . . 459 Targeting Signals for Peroxisomal Membrane Proteins . . . . . . . . . .. . . . . . 460 Receptors for PTSs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 460 Peroxisomal Protein Import Deficiencies in Human Disease . . . . . . . . . . . . . 461 Mutations Responsible for Some Human Peroxisomal Disorders . . . . . . . . . . . 462 APPROACHES USED TO ELUCIDATE THE MECHANISM OF PROTEIN IMPORT INTO Peroxisomes . . . . . . . . . . . . . . . . . . . . . . . . . 463 In Vitro Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463 Microinjection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463 Semi-intact Cells . ... . . . . . . . . . . . . . . . . . .... . . . .. . . . . . . . . . . 464 Mechanistic Aspects of Protein Import Into the Peroxisomal Matrix . . . . . . .. 464 DISTINCT STEPS IN PEROXISOME BIOGENESIS . . . . . . . . . . . . . . . .. . . 465 GENERAL PROPERTIES OF PEROXISOME ASSEMBLY/IMPORT MUTANTS . 468 Mutants Affected in Peroxisome Proliferation . . . . . . . . . . . . . . . . . , 468 Mutants Affected in Peroxisome Growth . . . . .... . . . ...... . . . . , . . . . 468

Richard N. Trelease - One of the best experts on this subject based on the ideXlab platform.

  • 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, 2006
    Co-Authors: Robert T Mullen, Richard N. Trelease
    Abstract:

    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.

  • 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, 2006
    Co-Authors: Robert T Mullen, Richard N. Trelease
    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. © 2006 Elsevier B.V. All rights reserved.

Related terms

Peroxisomes - 15 days free trial to Access Experts & Abstracts