1
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Zhang J, Qiu R, Xie S, Rasmussen M, Xiang X. VezA/vezatin facilitates proper assembly of the dynactin complex in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590248. [PMID: 38659795 PMCID: PMC11042379 DOI: 10.1101/2024.04.19.590248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Cytoplasmic dynein-mediated intracellular transport needs the multi-component dynactin complex for cargo binding and motor activation. However, cellular factors involved in dynactin assembly remain unexplored. Here we found in Aspergillus nidulans that the vezatin homolog VezA is important for dynactin assembly. VezA affects the microtubule plus-end accumulation of dynein before cargo binding and cargo adapter-mediated dynein activation, two processes that both need dynactin. The dynactin complex contains multiple components including an Arp1 (actin-related protein 1) mini-filament associated with a pointed-end sub-complex. VezA physically interacts with dynactin either directly or indirectly via the Arp1 mini-filament and its pointed-end sub-complex. Loss of VezA causes a defect in dynactin integrity, most likely by affecting the connection between the Arp1 mini-filament and its pointed-end sub-complex. Using various dynactin mutants, we further revealed that assembly of the dynactin complex must be highly coordinated. Together, these results shed important new light on dynactin assembly in vivo.
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Affiliation(s)
- Jun Zhang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Rongde Qiu
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Sean Xie
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
- Montgomery Blair High School, Silver Spring, Maryland, USA
| | - Megan Rasmussen
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences- F. Edward Hébert School of Medicine, Bethesda, Maryland 20814, USA
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2
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Luo KR, Huang NC, Chang YH, Jan YW, Yu TS. Arabidopsis cyclophilins direct intracellular transport of mobile mRNA via organelle hitchhiking. NATURE PLANTS 2024; 10:161-171. [PMID: 38177664 DOI: 10.1038/s41477-023-01597-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 11/24/2023] [Indexed: 01/06/2024]
Abstract
Plants convert external cues into mobile mRNAs to synchronize meristematic differentiation with environmental dynamics. These mRNAs are selectively transported to intercellular pores, plasmodesmata (PD), for cell-to-cell movement. However, how plants recognize and deliver mobile mRNAs to PD remains unknown. Here we show that mobile mRNAs hitchhike on organelle trafficking to transport towards PD. Perturbed cytoskeleton organization or organelle trafficking severely disrupts the subcellular distribution of mobile mRNAs. Arabidopsis rotamase cyclophilins (ROCs), which are organelle-localized RNA-binding proteins, specifically bind mobile mRNAs on the surface of organelles to direct intracellular transport. Arabidopsis roc mutants exhibit phenotype alterations and disruptions in the transport of mobile mRNAs. These findings suggest that ROCs play a crucial role in facilitating the systemic delivery of mobile mRNAs. Our results highlight that an RNA-binding protein-mediated hitchhiking system is specifically recruited to orient plant mobile mRNAs for intercellular transport.
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Affiliation(s)
- Kai-Ren Luo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Nien-Chen Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Hsin Chang
- Institute of Plant Biology, National Taiwan University, Taipei, Taiwan
| | - Yu-Wen Jan
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Tien-Shin Yu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.
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3
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Otis JP, Mowry KL. Hitting the mark: Localization of mRNA and biomolecular condensates in health and disease. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1807. [PMID: 37393916 PMCID: PMC10758526 DOI: 10.1002/wrna.1807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/29/2023] [Accepted: 06/06/2023] [Indexed: 07/04/2023]
Abstract
Subcellular mRNA localization is critical to a multitude of biological processes such as development of cellular polarity, embryogenesis, tissue differentiation, protein complex formation, cell migration, and rapid responses to environmental stimuli and synaptic depolarization. Our understanding of the mechanisms of mRNA localization must now be revised to include formation and trafficking of biomolecular condensates, as several biomolecular condensates that transport and localize mRNA have recently been discovered. Disruptions in mRNA localization can have catastrophic effects on developmental processes and biomolecular condensate biology and have been shown to contribute to diverse diseases. A fundamental understanding of mRNA localization is essential to understanding how aberrations in this biology contribute the etiology of numerous cancers though support of cancer cell migration and biomolecular condensate dysregulation, as well as many neurodegenerative diseases, through misregulation of mRNA localization and biomolecular condensate biology. This article is categorized under: RNA Export and Localization > RNA Localization RNA in Disease and Development > RNA in Disease RNA in Disease and Development > RNA in Development.
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Affiliation(s)
- Jessica P. Otis
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, United States, 02912
| | - Kimberly L. Mowry
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, United States, 02912
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4
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Patil SS, Panchal V, Røstbø T, Romanyuk S, Hollås H, Brenk R, Grindheim AK, Vedeler A. RNA-binding is an ancient trait of the Annexin family. Front Cell Dev Biol 2023; 11:1161588. [PMID: 37397259 PMCID: PMC10311354 DOI: 10.3389/fcell.2023.1161588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 05/25/2023] [Indexed: 07/04/2023] Open
Abstract
Introduction: The regulation of intracellular functions in mammalian cells involves close coordination of cellular processes. During recent years it has become evident that the sorting, trafficking and distribution of transport vesicles and mRNA granules/complexes are closely coordinated to ensure effective simultaneous handling of all components required for a specific function, thereby minimizing the use of cellular energy. Identification of proteins acting at the crossroads of such coordinated transport events will ultimately provide mechanistic details of the processes. Annexins are multifunctional proteins involved in a variety of cellular processes associated with Ca2+-regulation and lipid binding, linked to the operation of both the endocytic and exocytic pathways. Furthermore, certain Annexins have been implicated in the regulation of mRNA transport and translation. Since Annexin A2 binds specific mRNAs via its core structure and is also present in mRNP complexes, we speculated whether direct association with RNA could be a common property of the mammalian Annexin family sharing a highly similar core structure. Methods and results: Therefore, we performed spot blot and UV-crosslinking experiments to assess the mRNA binding abilities of the different Annexins, using annexin A2 and c-myc 3'UTRs as well as c-myc 5'UTR as baits. We supplemented the data with immunoblot detection of selected Annexins in mRNP complexes derived from the neuroendocrine rat PC12 cells. Furthermore, biolayer interferometry was used to determine the KD of selected Annexin-RNA interactions, which indicated distinct affinities. Amongst these Annexins, Annexin A13 and the core structures of Annexin A7, Annexin A11 bind c-myc 3'UTR with KDs in the nanomolar range. Of the selected Annexins, only Annexin A2 binds the c-myc 5'UTR indicating some selectivity. Discussion: The oldest members of the mammalian Annexin family share the ability to associate with RNA, suggesting that RNA-binding is an ancient trait of this protein family. Thus, the combined RNA- and lipid-binding properties of the Annexins make them attractive candidates to participate in coordinated long-distance transport of membrane vesicles and mRNAs regulated by Ca2+. The present screening results can thus pave the way for studies of the multifunctional Annexins in a novel cellular context.
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Affiliation(s)
- Sudarshan S. Patil
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Vipul Panchal
- Biorecognition Unit, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Trude Røstbø
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Sofya Romanyuk
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Hanne Hollås
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Ruth Brenk
- Biorecognition Unit, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Ann Kari Grindheim
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Anni Vedeler
- Neurotargeting Group, Department of Biomedicine, University of Bergen, Bergen, Norway
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5
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Bauer KE, de Queiroz BR, Kiebler MA, Besse F. RNA granules in neuronal plasticity and disease. Trends Neurosci 2023:S0166-2236(23)00104-2. [PMID: 37202301 DOI: 10.1016/j.tins.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/11/2023] [Accepted: 04/16/2023] [Indexed: 05/20/2023]
Abstract
RNA granules are dynamic entities controlling the spatiotemporal distribution and translation of RNA molecules. In neurons, a variety of RNA granules exist both in the soma and in cellular processes. They contain transcripts encoding signaling and synaptic proteins as well as RNA-binding proteins causally linked to several neurological disorders. In this review, we highlight that neuronal RNA granules exhibit properties of biomolecular condensates that are regulated upon maturation and physiological aging and how they are reversibly remodeled in response to neuronal activity to control local protein synthesis and ultimately synaptic plasticity. Moreover, we propose a framework of how neuronal RNA granules mature over time in healthy conditions and how they transition into pathological inclusions in the context of late-onset neurodegenerative diseases.
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Affiliation(s)
- Karl E Bauer
- Biomedical Center (BMC), Department of Anatomy and Cell Biology, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Bruna R de Queiroz
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France
| | - Michael A Kiebler
- Biomedical Center (BMC), Department of Anatomy and Cell Biology, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany.
| | - Florence Besse
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France.
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6
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Zhang L, Si Q, Yang K, Zhang W, Okita TW, Tian L. mRNA Localization to the Endoplasmic Reticulum in Plant Endosperm Cells. Int J Mol Sci 2022; 23:13511. [PMID: 36362297 PMCID: PMC9656906 DOI: 10.3390/ijms232113511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/30/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Subcellular mRNA localization is an evolutionarily conserved mechanism to spatially and temporally drive local translation and, in turn, protein targeting. Hence, this mechanism achieves precise control of gene expression and establishes functional and structural networks during cell growth and development as well as during stimuli response. Since its discovery in ascidian eggs, mRNA localization has been extensively studied in animal and yeast cells. Although our knowledge of subcellular mRNA localization in plant cells lags considerably behind other biological systems, mRNA localization to the endoplasmic reticulum (ER) has also been well established since its discovery in cereal endosperm cells in the early 1990s. Storage protein mRNA targeting to distinct subdomains of the ER determines efficient accumulation of the corresponding proteins in different endosomal storage sites and, in turn, underlies storage organelle biogenesis in cereal grains. The targeting process requires the presence of RNA localization elements, also called zipcodes, and specific RNA-binding proteins that recognize and bind these zipcodes and recruit other factors to mediate active transport. Here, we review the current knowledge of the mechanisms and functions of mRNA localization to the ER in plant cells and address directions for future research.
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Affiliation(s)
- Laining Zhang
- Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China
| | - Qidong Si
- Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China
| | - Kejie Yang
- Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China
| | - Wenwei Zhang
- Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China
| | - Thomas W. Okita
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164, USA
| | - Li Tian
- Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, College of Horticulture Science, Zhejiang A&F University, Hangzhou 310007, China
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7
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Christensen JR, Reck-Peterson SL. Hitchhiking Across Kingdoms: Cotransport of Cargos in Fungal, Animal, and Plant Cells. Annu Rev Cell Dev Biol 2022; 38:155-178. [PMID: 35905769 PMCID: PMC10967659 DOI: 10.1146/annurev-cellbio-120420-104341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Eukaryotic cells across the tree of life organize their subcellular components via intracellular transport mechanisms. In canonical transport, myosin, kinesin, and dynein motor proteins interact with cargos via adaptor proteins and move along filamentous actin or microtubule tracks. In contrast to this canonical mode, hitchhiking is a newly discovered mode of intracellular transport in which a cargo attaches itself to an already-motile cargo rather than directly associating with a motor protein itself. Many cargos including messenger RNAs, protein complexes, and organelles hitchhike on membrane-bound cargos. Hitchhiking-like behaviors have been shown to impact cellular processes including local protein translation, long-distance signaling, and organelle network reorganization. Here, we review instances of cargo hitchhiking in fungal, animal, and plant cells and discuss the potential cellular and evolutionary importance of hitchhiking in these different contexts.
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Affiliation(s)
- Jenna R Christensen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA; ,
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA; ,
- Department of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, California, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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8
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Solovyev AG, Atabekova AK, Lezzhov AA, Solovieva AD, Chergintsev DA, Morozov SY. Distinct Mechanisms of Endomembrane Reorganization Determine Dissimilar Transport Pathways in Plant RNA Viruses. PLANTS 2022; 11:plants11182403. [PMID: 36145804 PMCID: PMC9504206 DOI: 10.3390/plants11182403] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/02/2022] [Accepted: 09/13/2022] [Indexed: 11/22/2022]
Abstract
Plant viruses exploit the endomembrane system of infected cells for their replication and cell-to-cell transport. The replication of viral RNA genomes occurs in the cytoplasm in association with reorganized endomembrane compartments induced by virus-encoded proteins and is coupled with the virus intercellular transport via plasmodesmata that connect neighboring cells in plant tissues. The transport of virus genomes to and through plasmodesmata requires virus-encoded movement proteins (MPs). Distantly related plant viruses encode different MP sets, or virus transport systems, which vary in the number of MPs and their properties, suggesting their functional differences. Here, we discuss two distinct virus transport pathways based on either the modification of the endoplasmic reticulum tubules or the formation of motile vesicles detached from the endoplasmic reticulum and targeted to endosomes. The viruses with the movement proteins encoded by the triple gene block exemplify the first, and the potyviral system is the example of the second type. These transport systems use unrelated mechanisms of endomembrane reorganization. We emphasize that the mode of virus interaction with cell endomembranes determines the mechanism of plant virus cell-to-cell transport.
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Affiliation(s)
- Andrey G. Solovyev
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
- All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
| | - Anastasia K. Atabekova
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Alexander A. Lezzhov
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
| | - Anna D. Solovieva
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Denis A. Chergintsev
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Sergey Y. Morozov
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
- Correspondence: ; Tel.: +7-(495)-939-31-98
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9
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Wang S, Zhao X, Sun K, Bateer H, Wang W. The Genome Sequence of Brucella abortus vaccine strain A19 provides insights on its virulence attenuation compared to Brucella abortus strain 9-941. Gene 2022; 830:146521. [PMID: 35447245 DOI: 10.1016/j.gene.2022.146521] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/20/2021] [Accepted: 04/15/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Brucellosis is a widespread disease that affects animals and humans. The live attenuated Brucella abortus A19 strain is used for vaccination against brucellosis in China. In addition, the main mechanisms supporting the residual toxicity of A19 have not been elucidated. Here, we performed a comprehensive comparative analysis of the genome-wide sequence of A19 against the whole genome sequences of the published virulent reference strain 9-941. The primary objective of this study was to identify candidate virulence genes by systematically comparing the genomic sequences between the two genomes. RESULTS This analysis revealed two deletion regions in the A19 genome, in which all included large fragments of 63 bp, and one of their gene function is related to ABC transporter permease protein. In addition, we have identified minor mutations in important virulence-related genes that can be used to determine the underlying mechanisms of virulence attenuation. The function of its virulence gene covers LysR family transcriptional regulator, outer membrane, MFS transporter and oxidoreductase etc. At the same time, a PCR differential diagnosis method was constructed, which can distinguish A19, S19 and most other commonly used Brucella viruent strains and vaccine strains. CONCLUSION The data may help to provide resources for further detailed analysis of mechanisms for other Brucella vaccines. It laid the foundation for further distinguishing between vaccine immunity and virulent strains infection.
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Affiliation(s)
- Shuyi Wang
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture/College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China; Inner Mongolia Autonomous Region Comprehensive Center for Disease Control and Prevention, Hohhot, Inner Mongolia 010031, China
| | - Xueliang Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Ke Sun
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture/College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Huhe Bateer
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture/College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Wenlong Wang
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture/College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China.
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10
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A MademoiseLLE domain binding platform links the key RNA transporter to endosomes. PLoS Genet 2022; 18:e1010269. [PMID: 35727840 PMCID: PMC9249222 DOI: 10.1371/journal.pgen.1010269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 07/01/2022] [Accepted: 05/20/2022] [Indexed: 11/19/2022] Open
Abstract
Spatiotemporal expression can be achieved by transport and translation of mRNAs at defined subcellular sites. An emerging mechanism mediating mRNA trafficking is microtubule-dependent co-transport on shuttling endosomes. Although progress has been made in identifying various components of the endosomal mRNA transport machinery, a mechanistic understanding of how these RNA-binding proteins are connected to endosomes is still lacking. Here, we demonstrate that a flexible MademoiseLLE (MLLE) domain platform within RNA-binding protein Rrm4 of Ustilago maydis is crucial for endosomal attachment. Our structure/function analysis uncovered three MLLE domains at the C-terminus of Rrm4 with a functionally defined hierarchy. MLLE3 recognises two PAM2-like sequences of the adaptor protein Upa1 and is essential for endosomal shuttling of Rrm4. MLLE1 and MLLE2 are most likely accessory domains exhibiting a variable binding mode for interaction with currently unknown partners. Thus, endosomal attachment of the mRNA transporter is orchestrated by a sophisticated MLLE domain binding platform. Eukaryotic cells rely on sophisticated intracellular logistics. Macromolecules like mRNA must be transported to defined subcellular destinations for local translation. This is mediated by active transport along the cytoskeleton. Endosomes are carrier vehicles that shuttle along microtubules by the action of molecular motors. It is currently unclear how mRNAs are attached mechanistically to these membranous units during transport. We study the model microorganism Ustilago maydis where numerous components of endosomal mRNA transport have already been identified. Previously, we found that the key RNA-binding protein Rrm4 interacts with the endosomal adaptor protein Upa1. Here, we perform a structure/function analysis and discovered that Rrm4 contains not one but three different versions of a protein-protein interaction domain, called the MademoiseLLE domain, to facilitate the attachment with transport endosomes. Importantly, they function with a strict hierarchy with one essential domain and the others play accessory roles. This is currently, the most detailed mechanistic description of how an RNA-binding protein and its bound cargo mRNAs are attached to endosomes. The usage of three similar protein-protein interaction domains forming a complex binding platform with a defined hierarchy might be operational also in other unknown protein-protein interactions.
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11
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Bioinformatic Analysis Predicts a Novel Genetic Module Related to Triple Gene and Binary Movement Blocks of Plant Viruses: Tetra-Cistron Movement Block. Biomolecules 2022; 12:biom12070861. [PMID: 35883420 PMCID: PMC9313169 DOI: 10.3390/biom12070861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/14/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022] Open
Abstract
Previous studies have shown that the RNA genomes of some plant viruses encode two related genetic modules required for virus movement over the host body, containing two or three genes and named the binary movement block (BMB) and triple gene block (TGB), respectively. In this paper, we predict a novel putative-related movement gene module, called the tetra-cistron movement block (TCMB), in the virus-like transcriptome assemblies of the moss Dicranum scoparium and the Antarctic flowering plant Colobanthus quitensis. These TCMBs are encoded by smaller RNA components of putative two-component viruses related to plant benyviruses. Similar to the RNA2 of benyviruses, TCMB-containing RNAs have the 5′-terminal coat protein gene and include the RNA helicase gene which is followed by two small overlapping cistrons encoding hydrophobic proteins with a distant sequence similarity to the TGB2 and TGB3 proteins. Unlike TGB, TCMB also includes a fourth 5′-terminal gene preceding the helicase gene and coding for a protein showing a similarity to the double-stranded RNA-binding proteins of the DSRM AtDRB-like superfamily. Additionally, based on phylogenetic analysis, we suggest the involvement of replicative beny-like helicases in the evolution of the BMB and TCMB movement genetic modules.
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12
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Houghton OH, Mizielinska S, Gomez-Suaga P. The Interplay Between Autophagy and RNA Homeostasis: Implications for Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Front Cell Dev Biol 2022; 10:838402. [PMID: 35573690 PMCID: PMC9096704 DOI: 10.3389/fcell.2022.838402] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 04/14/2022] [Indexed: 01/18/2023] Open
Abstract
Amyotrophic lateral sclerosis and frontotemporal dementia are neurodegenerative disorders that lie on a disease spectrum, sharing genetic causes and pathology, and both without effective therapeutics. Two pathways that have been shown to play major roles in disease pathogenesis are autophagy and RNA homeostasis. Intriguingly, there is an increasing body of evidence suggesting a critical interplay between these pathways. Autophagy is a multi-stage process for bulk and selective clearance of malfunctional cellular components, with many layers of regulation. Although the majority of autophagy research focuses on protein degradation, it can also mediate RNA catabolism. ALS/FTD-associated proteins are involved in many stages of autophagy and autophagy-mediated RNA degradation, particularly converging on the clearance of persistent pathological stress granules. In this review, we will summarise the progress in understanding the autophagy-RNA homeostasis interplay and how that knowledge contributes to our understanding of the pathobiology of ALS/FTD.
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Affiliation(s)
- O H Houghton
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom.,UK Dementia Research Institute at King's College London, London, United Kingdom
| | - S Mizielinska
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom.,UK Dementia Research Institute at King's College London, London, United Kingdom
| | - P Gomez-Suaga
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, United Kingdom.,Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Enfermería y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
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13
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Hussain A, Asif N, Pirzada AR, Noureen A, Shaukat J, Burhan A, Zaynab M, Ali E, Imran K, Ameen A, Mahmood MA, Nazar A, Mukhtar MS. Genome wide study of cysteine rich receptor like proteins in Gossypium sp. Sci Rep 2022; 12:4885. [PMID: 35318409 PMCID: PMC8941122 DOI: 10.1038/s41598-022-08943-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 03/11/2022] [Indexed: 02/08/2023] Open
Abstract
Cysteine-rich receptor-like-kinases (CRKs), a transmembrane subfamily of receptor-like kinase, play crucial roles in plant adaptation. As such cotton is the major source of fiber for the textile industry, but environmental stresses are limiting its growth and production. Here, we have performed a deep computational analysis of CRKs in five Gossypium species, including G. arboreum (60 genes), G. raimondii (74 genes), G. herbaceum (65 genes), G. hirsutum (118 genes), and G. barbadense (120 genes). All identified CRKs were classified into 11 major classes and 43 subclasses with the finding of several novel CRK-associated domains including ALMT, FUSC_2, Cript, FYVE, and Pkinase. Of these, DUF26_DUF26_Pkinase_Tyr was common and had elevated expression under different biotic and abiotic stresses. Moreover, the 35 land plants comparison identified several new CRKs domain-architectures. Likewise, several SNPs and InDels were observed in CLCuD resistant G. hirsutum. The miRNA target side prediction and their expression profiling in different tissues predicted miR172 as a major CRK regulating miR. The expression profiling of CRKs identified multiple clusters with co-expression under certain stress conditions. The expression analysis under CLCuD highlighted the role of GhCRK057, GhCRK059, GhCRK058, and GhCRK081 in resistant accession. Overall, these results provided primary data for future potential functional analysis as well as a reference study for other agronomically important crops.
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Affiliation(s)
- Athar Hussain
- Genomics Lab, School of Food and Agricultural Sciences (SFAS), University of Management and Technology (UMT), Lahore, 54000, Pakistan.
| | - Naila Asif
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Abdul Rafay Pirzada
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Azka Noureen
- National Institute for Biotechnology and Genetic Engineering (NIBGE), College of Pakistan Institute of Engineering and Applied Sciences (PIEAS), Faisalabad, 38000, Pakistan.,PMAS-Arid Agriculture University Rawalpindi, Rawalpindi, 46300, Pakistan
| | - Javeria Shaukat
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Akif Burhan
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Madiha Zaynab
- Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Sciences, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 51807, China
| | - Ejaz Ali
- Center of Excellence in Molecular Biology, University of Punjab, Lahore, 54000, Pakistan
| | - Koukab Imran
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Ayesha Ameen
- Office of Research Innovation and Commercialization, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - Muhammad Arslan Mahmood
- National Institute for Biotechnology and Genetic Engineering (NIBGE), College of Pakistan Institute of Engineering and Applied Sciences (PIEAS), Faisalabad, 38000, Pakistan
| | - Aquib Nazar
- Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54000, Pakistan
| | - M Shahid Mukhtar
- Department of Biology, the University of Alabama at Birmingham, 1300 University Blvd., Birmingham, AL, 35294, USA
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14
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Müntjes K, Devan SK, Reichert AS, Feldbrügge M. Linking transport and translation of mRNAs with endosomes and mitochondria. EMBO Rep 2021; 22:e52445. [PMID: 34402186 PMCID: PMC8490996 DOI: 10.15252/embr.202152445] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 07/06/2021] [Accepted: 07/27/2021] [Indexed: 01/01/2023] Open
Abstract
In eukaryotic cells, proteins are targeted to their final subcellular locations with precise timing. A key underlying mechanism is the active transport of cognate mRNAs, which in many systems can be linked intimately to membrane trafficking. A prominent example is the long-distance endosomal transport of mRNAs and their local translation. Here, we describe current highlights of fundamental mechanisms of the underlying transport process as well as of biological functions ranging from endosperm development in plants to fungal pathogenicity and neuronal processes. Translation of endosome-associated mRNAs often occurs at the cytoplasmic surface of endosomes, a process that is needed for membrane-assisted formation of heteromeric protein complexes and for accurate subcellular targeting of proteins. Importantly, endosome-coupled translation of mRNAs encoding mitochondrial proteins, for example, seems to be particularly important for efficient organelle import and for regulating subcellular mitochondrial activity. In essence, these findings reveal a new mechanism of loading newly synthesised proteins onto endocytic membranes enabling intimate crosstalk between organelles. The novel link between endosomes and mitochondria adds an inspiring new level of complexity to trafficking and organelle biology.
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Affiliation(s)
- Kira Müntjes
- Institute of MicrobiologyCluster of Excellence on Plant SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Senthil Kumar Devan
- Institute of MicrobiologyCluster of Excellence on Plant SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology IMedical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Michael Feldbrügge
- Institute of MicrobiologyCluster of Excellence on Plant SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany
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15
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Rajgor D, Welle TM, Smith KR. The Coordination of Local Translation, Membranous Organelle Trafficking, and Synaptic Plasticity in Neurons. Front Cell Dev Biol 2021; 9:711446. [PMID: 34336865 PMCID: PMC8317219 DOI: 10.3389/fcell.2021.711446] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 06/14/2021] [Indexed: 12/16/2022] Open
Abstract
Neurons are highly complex polarized cells, displaying an extraordinary degree of spatial compartmentalization. At presynaptic and postsynaptic sites, far from the cell body, local protein synthesis is utilized to continually modify the synaptic proteome, enabling rapid changes in protein production to support synaptic function. Synapses undergo diverse forms of plasticity, resulting in long-term, persistent changes in synapse strength, which are paramount for learning, memory, and cognition. It is now well-established that local translation of numerous synaptic proteins is essential for many forms of synaptic plasticity, and much work has gone into deciphering the strategies that neurons use to regulate activity-dependent protein synthesis. Recent studies have pointed to a coordination of the local mRNA translation required for synaptic plasticity and the trafficking of membranous organelles in neurons. This includes the co-trafficking of RNAs to their site of action using endosome/lysosome “transports,” the regulation of activity-dependent translation at synapses, and the role of mitochondria in fueling synaptic translation. Here, we review our current understanding of these mechanisms that impact local translation during synaptic plasticity, providing an overview of these novel and nuanced regulatory processes involving membranous organelles in neurons.
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Affiliation(s)
- Dipen Rajgor
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Theresa M Welle
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Katharine R Smith
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, United States
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16
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Das S, Vera M, Gandin V, Singer RH, Tutucci E. Intracellular mRNA transport and localized translation. Nat Rev Mol Cell Biol 2021; 22:483-504. [PMID: 33837370 PMCID: PMC9346928 DOI: 10.1038/s41580-021-00356-8] [Citation(s) in RCA: 126] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2021] [Indexed: 02/08/2023]
Abstract
Fine-tuning cellular physiology in response to intracellular and environmental cues requires precise temporal and spatial control of gene expression. High-resolution imaging technologies to detect mRNAs and their translation state have revealed that all living organisms localize mRNAs in subcellular compartments and create translation hotspots, enabling cells to tune gene expression locally. Therefore, mRNA localization is a conserved and integral part of gene expression regulation from prokaryotic to eukaryotic cells. In this Review, we discuss the mechanisms of mRNA transport and local mRNA translation across the kingdoms of life and at organellar, subcellular and multicellular resolution. We also discuss the properties of messenger ribonucleoprotein and higher order RNA granules and how they may influence mRNA transport and local protein synthesis. Finally, we summarize the technological developments that allow us to study mRNA localization and local translation through the simultaneous detection of mRNAs and proteins in single cells, mRNA and nascent protein single-molecule imaging, and bulk RNA and protein detection methods.
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Affiliation(s)
- Sulagna Das
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, NY, USA.,Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, NY, USA
| | - Maria Vera
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | | | - Robert H. Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, NY, USA.,Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, NY, USA.,Janelia Research Campus of the HHMI, Ashburn, VA, USA.,;
| | - Evelina Tutucci
- Systems Biology Lab, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,;
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17
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Rodrigues EC, Grawenhoff J, Baumann SJ, Lorenzon N, Maurer SP. Mammalian Neuronal mRNA Transport Complexes: The Few Knowns and the Many Unknowns. Front Integr Neurosci 2021; 15:692948. [PMID: 34211375 PMCID: PMC8239176 DOI: 10.3389/fnint.2021.692948] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/25/2021] [Indexed: 11/13/2022] Open
Abstract
Hundreds of messenger RNAs (mRNAs) are transported into neurites to provide templates for the assembly of local protein networks. These networks enable a neuron to configure different cellular domains for specialized functions. According to current evidence, mRNAs are mostly transported in rather small packages of one to three copies, rarely containing different transcripts. This opens up fascinating logistic problems: how are hundreds of different mRNA cargoes sorted into distinct packages and how are they coupled to and released from motor proteins to produce the observed mRNA distributions? Are all mRNAs transported by the same transport machinery, or are there different adaptors or motors for different transcripts or classes of mRNAs? A variety of often indirect evidence exists for the involvement of proteins in mRNA localization, but relatively little is known about the essential activities required for the actual transport process. Here, we summarize the different types of available evidence for interactions that connect mammalian mRNAs to motor proteins to highlight at which point further research is needed to uncover critical missing links. We further argue that a combination of discovery approaches reporting direct interactions, in vitro reconstitution, and fast perturbations in cells is an ideal future strategy to unravel essential interactions and specific functions of proteins in mRNA transport processes.
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Affiliation(s)
- Elsa C. Rodrigues
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Julia Grawenhoff
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Sebastian J. Baumann
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Nicola Lorenzon
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Sebastian P. Maurer
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
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18
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RNA transport and local translation in neurodevelopmental and neurodegenerative disease. Nat Neurosci 2021; 24:622-632. [PMID: 33510479 PMCID: PMC8860725 DOI: 10.1038/s41593-020-00785-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 12/17/2020] [Indexed: 02/08/2023]
Abstract
Neurons decentralize protein synthesis from the cell body to support the active metabolism of remote dendritic and axonal compartments. The neuronal RNA transport apparatus, composed of cis-acting RNA regulatory elements, neuronal transport granule proteins, and motor adaptor complexes, drives the long-distance RNA trafficking required for local protein synthesis. Over the past decade, advances in human genetics, subcellular biochemistry, and high-resolution imaging have implicated each member of the apparatus in several neurodegenerative diseases, establishing failed RNA transport and associated processes as a unifying pathomechanism. In this review, we deconstruct the RNA transport apparatus, exploring each constituent's role in RNA localization and illuminating their unique contributions to neurodegeneration.
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19
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Abouward R, Schiavo G. Walking the line: mechanisms underlying directional mRNA transport and localisation in neurons and beyond. Cell Mol Life Sci 2021; 78:2665-2681. [PMID: 33341920 PMCID: PMC8004493 DOI: 10.1007/s00018-020-03724-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/02/2020] [Accepted: 11/25/2020] [Indexed: 12/21/2022]
Abstract
Messenger RNA (mRNA) localisation enables a high degree of spatiotemporal control on protein synthesis, which contributes to establishing the asymmetric protein distribution required to set up and maintain cellular polarity. As such, a tight control of mRNA localisation is essential for many biological processes during development and in adulthood, such as body axes determination in Drosophila melanogaster and synaptic plasticity in neurons. The mechanisms controlling how mRNAs are localised, including diffusion and entrapment, local degradation and directed active transport, are largely conserved across evolution and have been under investigation for decades in different biological models. In this review, we will discuss the standing of the field regarding directional mRNA transport in light of the recent discovery that RNA can hitchhike on cytoplasmic organelles, such as endolysosomes, and the impact of these transport modalities on our understanding of neuronal function during development, adulthood and in neurodegeneration.
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Affiliation(s)
- Reem Abouward
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
- The Francis Crick Institute, 1 Midland Rd, London, NW1 1AT, UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK.
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20
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Versatile CRISPR/Cas9 Systems for Genome Editing in Ustilago maydis. J Fungi (Basel) 2021; 7:jof7020149. [PMID: 33670568 PMCID: PMC7922307 DOI: 10.3390/jof7020149] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/09/2021] [Accepted: 02/16/2021] [Indexed: 12/24/2022] Open
Abstract
The phytopathogenic smut fungus Ustilago maydis is a versatile model organism to study plant pathology, fungal genetics, and molecular cell biology. Here, we report several strategies to manipulate the genome of U. maydis by the CRISPR/Cas9 technology. These include targeted gene deletion via homologous recombination of short double-stranded oligonucleotides, introduction of point mutations, heterologous complementation at the genomic locus, and endogenous N-terminal tagging with the fluorescent protein mCherry. All applications are independent of a permanent selectable marker and only require transient expression of the endonuclease Cas9hf and sgRNA. The techniques presented here are likely to accelerate research in the U. maydis community but can also act as a template for genome editing in other important fungi.
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21
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Dalla Costa I, Buchanan CN, Zdradzinski MD, Sahoo PK, Smith TP, Thames E, Kar AN, Twiss JL. The functional organization of axonal mRNA transport and translation. Nat Rev Neurosci 2021; 22:77-91. [PMID: 33288912 PMCID: PMC8161363 DOI: 10.1038/s41583-020-00407-7] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2020] [Indexed: 12/13/2022]
Abstract
Axons extend for tremendously long distances from the neuronal soma and make use of localized mRNA translation to rapidly respond to different extracellular stimuli and physiological states. The locally synthesized proteins support many different functions in both developing and mature axons, raising questions about the mechanisms by which local translation is organized to ensure the appropriate responses to specific stimuli. Publications over the past few years have uncovered new mechanisms for regulating the axonal transport and localized translation of mRNAs, with several of these pathways converging on the regulation of cohorts of functionally related mRNAs - known as RNA regulons - that drive axon growth, axon guidance, injury responses, axon survival and even axonal mitochondrial function. Recent advances point to these different regulatory pathways as organizing platforms that allow the axon's proteome to be modulated to meet its physiological needs.
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Affiliation(s)
- Irene Dalla Costa
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Courtney N Buchanan
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | | | - Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Terika P Smith
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Elizabeth Thames
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Amar N Kar
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA.
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22
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Salogiannis J, Christensen JR, Songster LD, Aguilar-Maldonado A, Shukla N, Reck-Peterson SL. PxdA interacts with the DipA phosphatase to regulate peroxisome hitchhiking on early endosomes. Mol Biol Cell 2021; 32:492-503. [PMID: 33476181 PMCID: PMC8101442 DOI: 10.1091/mbc.e20-08-0559] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In canonical microtubule-based transport, adaptor proteins link cargoes to dynein and kinesin motors. Recently, an alternative mode of transport known as “hitchhiking” was discovered, where cargoes achieve motility by hitching a ride on already-motile cargoes, rather than attaching to a motor protein. Hitchhiking has been best studied in two filamentous fungi, Aspergillus nidulans and Ustilago maydis. In U. maydis, ribonucleoprotein complexes, peroxisomes, lipid droplets (LDs), and endoplasmic reticulum hitchhike on early endosomes (EEs). In A. nidulans, peroxisomes hitchhike using a putative molecular linker, peroxisome distribution mutant A (PxdA), which associates with EEs. However, whether other organelles use PxdA to hitchhike on EEs is unclear, as are the molecular mechanisms that regulate hitchhiking. Here we find that the proper distribution of LDs, mitochondria, and preautophagosomes do not require PxdA, suggesting that PxdA is a peroxisome-specific molecular linker. We identify two new pxdA alleles, including a point mutation (R2044P) that disrupts PxdA’s ability to associate with EEs and reduces peroxisome movement. We also identify a novel regulator of peroxisome hitchhiking, the phosphatase DipA. DipA colocalizes with EEs and its association with EEs relies on PxdA. Together, our data suggest that PxdA and the DipA phosphatase are specific regulators of peroxisome hitchhiking on EEs.
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Affiliation(s)
- John Salogiannis
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Jenna R Christensen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Livia D Songster
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093
| | - Adriana Aguilar-Maldonado
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Nandini Shukla
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 043210.,Department of Molecular Genetics, The Ohio State University, Columbus, OH 043210
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093.,Howard Hughes Medical Institute, Chevy Chase, MD 20815
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23
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Koppers M, Özkan N, Farías GG. Complex Interactions Between Membrane-Bound Organelles, Biomolecular Condensates and the Cytoskeleton. Front Cell Dev Biol 2020; 8:618733. [PMID: 33409284 PMCID: PMC7779554 DOI: 10.3389/fcell.2020.618733] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 12/03/2020] [Indexed: 12/13/2022] Open
Abstract
Membrane-bound and membraneless organelles/biomolecular condensates ensure compartmentalization into functionally distinct units enabling proper organization of cellular processes. Membrane-bound organelles form dynamic contacts with each other to enable the exchange of molecules and to regulate organelle division and positioning in coordination with the cytoskeleton. Crosstalk between the cytoskeleton and dynamic membrane-bound organelles has more recently also been found to regulate cytoskeletal organization. Interestingly, recent work has revealed that, in addition, the cytoskeleton and membrane-bound organelles interact with cytoplasmic biomolecular condensates. The extent and relevance of these complex interactions are just beginning to emerge but may be important for cytoskeletal organization and organelle transport and remodeling. In this review, we highlight these emerging functions and emphasize the complex interplay of the cytoskeleton with these organelles. The crosstalk between membrane-bound organelles, biomolecular condensates and the cytoskeleton in highly polarized cells such as neurons could play essential roles in neuronal development, function and maintenance.
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Affiliation(s)
| | | | - Ginny G. Farías
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
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24
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Xiang X, Qiu R. Cargo-Mediated Activation of Cytoplasmic Dynein in vivo. Front Cell Dev Biol 2020; 8:598952. [PMID: 33195284 PMCID: PMC7649786 DOI: 10.3389/fcell.2020.598952] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/07/2020] [Indexed: 12/12/2022] Open
Abstract
Cytoplasmic dynein-1 is a minus-end-directed microtubule motor that transports a variety of cargoes including early endosomes, late endosomes and other organelles. In many cell types, dynein accumulates at the microtubule plus end, where it interacts with its cargo to be moved toward the minus end. Dynein binds to its various cargoes via the dynactin complex and specific cargo adapters. Dynactin and some of the coiled-coil-domain-containing cargo adapters not only link dynein to cargo but also activate dynein motility, which implies that dynein is activated by its cellular cargo. Structural studies indicate that a dynein dimer switches between the autoinhibited phi state and an open state; and the binding of dynactin and a cargo adapter to the dynein tails causes the dynein motor domains to have a parallel configuration, allowing dynein to walk processively along a microtubule. Recently, the dynein regulator LIS1 has been shown to be required for dynein activation in vivo, and its mechanism of action involves preventing dynein from switching back to the autoinhibited state. In this review, we will discuss our current understanding of dynein activation and point out the gaps of knowledge on the spatial regulation of dynein in live cells. In addition, we will emphasize the importance of studying a complete set of dynein regulators for a better understanding of dynein regulation in vivo.
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Affiliation(s)
- Xin Xiang
- Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States
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25
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S Mogre S, Brown AI, Koslover EF. Getting around the cell: physical transport in the intracellular world. Phys Biol 2020; 17:061003. [PMID: 32663814 DOI: 10.1088/1478-3975/aba5e5] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Eukaryotic cells face the challenging task of transporting a variety of particles through the complex intracellular milieu in order to deliver, distribute, and mix the many components that support cell function. In this review, we explore the biological objectives and physical mechanisms of intracellular transport. Our focus is on cytoplasmic and intra-organelle transport at the whole-cell scale. We outline several key biological functions that depend on physically transporting components across the cell, including the delivery of secreted proteins, support of cell growth and repair, propagation of intracellular signals, establishment of organelle contacts, and spatial organization of metabolic gradients. We then review the three primary physical modes of transport in eukaryotic cells: diffusive motion, motor-driven transport, and advection by cytoplasmic flow. For each mechanism, we identify the main factors that determine speed and directionality. We also highlight the efficiency of each transport mode in fulfilling various key objectives of transport, such as particle mixing, directed delivery, and rapid target search. Taken together, the interplay of diffusion, molecular motors, and flows supports the intracellular transport needs that underlie a broad variety of biological phenomena.
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Affiliation(s)
- Saurabh S Mogre
- Department of Physics, University of California, San Diego, San Diego, California 92093, United States of America
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26
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Stein V, Blank-Landeshammer B, Müntjes K, Märker R, Teichert I, Feldbrügge M, Sickmann A, Kück U. The STRIPAK signaling complex regulates dephosphorylation of GUL1, an RNA-binding protein that shuttles on endosomes. PLoS Genet 2020; 16:e1008819. [PMID: 32997654 PMCID: PMC7550108 DOI: 10.1371/journal.pgen.1008819] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 10/12/2020] [Accepted: 08/17/2020] [Indexed: 12/03/2022] Open
Abstract
The striatin-interacting phosphatase and kinase (STRIPAK) multi-subunit signaling complex is highly conserved within eukaryotes. In fungi, STRIPAK controls multicellular development, morphogenesis, pathogenicity, and cell-cell recognition, while in humans, certain diseases are related to this signaling complex. To date, phosphorylation and dephosphorylation targets of STRIPAK are still widely unknown in microbial as well as animal systems. Here, we provide an extended global proteome and phosphoproteome study using the wild type as well as STRIPAK single and double deletion mutants (Δpro11, Δpro11Δpro22, Δpp2Ac1Δpro22) from the filamentous fungus Sordaria macrospora. Notably, in the deletion mutants, we identified the differential phosphorylation of 129 proteins, of which 70 phosphorylation sites were previously unknown. Included in the list of STRIPAK targets are eight proteins with RNA recognition motifs (RRMs) including GUL1. Knockout mutants and complemented transformants clearly show that GUL1 affects hyphal growth and sexual development. To assess the role of GUL1 phosphorylation on fungal development, we constructed phospho-mimetic and -deficient mutants of GUL1 residues. While S180 was dephosphorylated in a STRIPAK-dependent manner, S216, and S1343 served as non-regulated phosphorylation sites. While the S1343 mutants were indistinguishable from wild type, phospho-deficiency of S180 and S216 resulted in a drastic reduction in hyphal growth, and phospho-deficiency of S216 also affects sexual fertility. These results thus suggest that differential phosphorylation of GUL1 regulates developmental processes such as fruiting body maturation and hyphal morphogenesis. Moreover, genetic interaction studies provide strong evidence that GUL1 is not an integral subunit of STRIPAK. Finally, fluorescence microscopy revealed that GUL1 co-localizes with endosomal marker proteins and shuttles on endosomes. Here, we provide a new mechanistic model that explains how STRIPAK-dependent and -independent phosphorylation of GUL1 regulates sexual development and asexual growth.
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Affiliation(s)
- Valentina Stein
- Allgemeine und Molekulare Botanik, Ruhr-Universität, Bochum, Germany
| | | | - Kira Müntjes
- Institut für Mikrobiologie, Cluster of Excellence on Plant Sciences, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Ramona Märker
- Allgemeine und Molekulare Botanik, Ruhr-Universität, Bochum, Germany
| | - Ines Teichert
- Allgemeine und Molekulare Botanik, Ruhr-Universität, Bochum, Germany
| | - Michael Feldbrügge
- Institut für Mikrobiologie, Cluster of Excellence on Plant Sciences, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund, Germany
| | - Ulrich Kück
- Allgemeine und Molekulare Botanik, Ruhr-Universität, Bochum, Germany
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27
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Turner-Bridger B, Caterino C, Cioni JM. Molecular mechanisms behind mRNA localization in axons. Open Biol 2020; 10:200177. [PMID: 32961072 PMCID: PMC7536069 DOI: 10.1098/rsob.200177] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/01/2020] [Indexed: 12/12/2022] Open
Abstract
Messenger RNA (mRNA) localization allows spatiotemporal regulation of the proteome at the subcellular level. This is observed in the axons of neurons, where mRNA localization is involved in regulating neuronal development and function by orchestrating rapid adaptive responses to extracellular cues and the maintenance of axonal homeostasis through local translation. Here, we provide an overview of the key findings that have broadened our knowledge regarding how specific mRNAs are trafficked and localize to axons. In particular, we review transcriptomic studies investigating mRNA content in axons and the molecular principles underpinning how these mRNAs arrived there, including cis-acting mRNA sequences and trans-acting proteins playing a role. Further, we discuss evidence that links defective axonal mRNA localization and pathological outcomes.
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Affiliation(s)
- Benita Turner-Bridger
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, UK
| | - Cinzia Caterino
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy
| | - Jean-Michel Cioni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy
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28
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Abildgaard MH, Brynjólfsdóttir SH, Frankel LB. The Autophagy-RNA Interplay: Degradation and Beyond. Trends Biochem Sci 2020; 45:845-857. [PMID: 32828649 DOI: 10.1016/j.tibs.2020.07.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/06/2020] [Accepted: 07/23/2020] [Indexed: 02/08/2023]
Abstract
Autophagy is a highly conserved degradation pathway that ensures nutrient recycling and removal of unwanted substrates. This process has a fundamental role in stress adaptation and maintenance of cellular homeostasis. Here, we discuss emerging aspects of the autophagy-RNA interplay, including autophagy-mediated degradation of RNA, RNA-binding proteins (RBPs), and ribonucleoprotein (RNP) complexes. Beyond degradation, we review new roles for autophagy players in the secretion and intracellular transport of RNA and related complexes. We discuss the physiological importance of these events for RNA homeostasis and gene expression programs, as well as their implications for disease, including cancer and neurodegeneration. Lastly, we examine how post-transcriptional regulation of autophagy, through specialized processing and selective translation of key transcripts, challenges and updates our current view of autophagy complexity.
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Affiliation(s)
| | | | - Lisa B Frankel
- Danish Cancer Society Research Center, Copenhagen, Denmark; Biotech Research and Innovation Centre, University of Copenhagen, Copenhagen, Denmark.
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29
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Char R, Pierre P. The RUFYs, a Family of Effector Proteins Involved in Intracellular Trafficking and Cytoskeleton Dynamics. Front Cell Dev Biol 2020; 8:779. [PMID: 32850870 PMCID: PMC7431699 DOI: 10.3389/fcell.2020.00779] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/24/2020] [Indexed: 12/12/2022] Open
Abstract
Intracellular trafficking is essential for cell structure and function. In order to perform key tasks such as phagocytosis, secretion or migration, cells must coordinate their intracellular trafficking, and cytoskeleton dynamics. This relies on certain classes of proteins endowed with specialized and conserved domains that bridge membranes with effector proteins. Of particular interest are proteins capable of interacting with membrane subdomains enriched in specific phosphatidylinositol lipids, tightly regulated by various kinases and phosphatases. Here, we focus on the poorly studied RUFY family of adaptor proteins, characterized by a RUN domain, which interacts with small GTP-binding proteins, and a FYVE domain, involved in the recognition of phosphatidylinositol 3-phosphate. We report recent findings on this protein family that regulates endosomal trafficking, cell migration and upon dysfunction, can lead to severe pathology at the organismal level.
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Affiliation(s)
- Rémy Char
- Aix Marseille Université, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Centre d'Immunologie de Marseille-Luminy, Marseille, France
| | - Philippe Pierre
- Aix Marseille Université, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Centre d'Immunologie de Marseille-Luminy, Marseille, France.,Institute for Research in Biomedicine and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, Aveiro, Portugal.,Shanghai Institute of Immunology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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30
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Tian L, Doroshenk KA, Zhang L, Fukuda M, Washida H, Kumamaru T, Okita T. Zipcode RNA-Binding Proteins and Membrane Trafficking Proteins Cooperate to Transport Glutelin mRNAs in Rice Endosperm. THE PLANT CELL 2020; 32:2566-2581. [PMID: 32471860 PMCID: PMC7401010 DOI: 10.1105/tpc.20.00111] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/12/2020] [Accepted: 05/24/2020] [Indexed: 05/04/2023]
Abstract
In rice (Oryza sativa) endosperm cells, mRNAs encoding glutelin and prolamine are translated on distinct cortical-endoplasmic reticulum (ER) subdomains (the cisternal-ER and protein body-ER), a process that facilitates targeting of their proteins to different endomembrane compartments. Although the cis- and trans-factors responsible for mRNA localization have been defined over the years, how these mRNAs are transported to the cortical ER has yet to be resolved. Here, we show that the two interacting glutelin zipcode RNA binding proteins (RBPs), RBP-P and RBP-L, form a quaternary complex with the membrane fusion factors n-ethylmaleimide-sensitive factor (NSF) and the small GTPase Rab5a, enabling mRNA transport on endosomes. Direct interaction of RBP-L with Rab5a, between NSF and RBP-P, and between NSF and Rab5a, were established. Biochemical and microscopic analyses confirmed the co-localization of these RBPs with NSF on Rab5a-positive endosomes that carry glutelin mRNAs. Analysis of a loss-of-function rab5a mutant showed that glutelin mRNA and the quaternary complex were mis-targeted to the extracellular paramural body structure formed by aborted endosomal trafficking, further confirming the involvement of endosomal trafficking in glutelin mRNA transport. Overall, these findings demonstrate that mRNA localization in plants co-opts membrane trafficking via the acquisition of new functional binding properties between RBPs and two essential membrane trafficking factors, thus defining an endosomal anchoring mechanism in mRNA localization.
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Affiliation(s)
- Li Tian
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
| | - Kelly A Doroshenk
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
| | - Laining Zhang
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
| | - Masako Fukuda
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
- Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Haruhiko Washida
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
| | | | - Thomas Okita
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340
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31
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Phase Separation in Membrane Biology: The Interplay between Membrane-Bound Organelles and Membraneless Condensates. Dev Cell 2020; 55:30-44. [PMID: 32726575 DOI: 10.1016/j.devcel.2020.06.033] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/14/2020] [Accepted: 06/26/2020] [Indexed: 12/13/2022]
Abstract
In eukaryotic cells, various membrane-bound organelles compartmentalize diverse cellular activities in a spatially and temporally controlled manner. Numerous membraneless organelles assembled via liquid-liquid phase separation (LLPS), known as condensates, also facilitate compartmentalization of cellular functions. Emerging evidence shows that these two organelle types interact in many biological processes. Membranes modulate the biogenesis and dynamics of phase-separated condensates by serving as assembly platforms or by forming direct contacts. Phase separation of membrane-associated proteins participates in various trafficking events, such as clustering of vesicles for temporally controlled fusion and storage, and transport of membraneless condensates on membrane-bound organelles. Phase separation also acts in cargo trafficking pathways by sorting and docking cargos for translocon-mediated transport across membranes, by shuttling cargos through the nuclear pore complex, and by triggering the formation of surrounding autophagosomes for delivery to lysosomes. The coordinated actions of membrane-bound and membraneless organelles ensure spatiotemporal control of various cellular functions.
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32
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Lee J, Hilgers F, Loeschke A, Jaeger KE, Feldbrügge M. Ustilago maydis Serves as a Novel Production Host for the Synthesis of Plant and Fungal Sesquiterpenoids. Front Microbiol 2020; 11:1655. [PMID: 32849341 PMCID: PMC7396576 DOI: 10.3389/fmicb.2020.01655] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/25/2020] [Indexed: 12/18/2022] Open
Abstract
Sesquiterpenoids are important secondary metabolites with various pharma- and nutraceutical properties. In particular, higher basidiomycetes possess a versatile biosynthetic repertoire for these bioactive compounds. To date, only a few microbial production systems for fungal sesquiterpenoids have been established. Here, we introduce Ustilago maydis as a novel production host. This model fungus is a close relative of higher basidiomycetes. It offers the advantage of metabolic compatibility and potential tolerance for substances toxic to other microorganisms. We successfully implemented a heterologous pathway to produce the carotenoid lycopene that served as a straightforward read-out for precursor pathway engineering. Overexpressing genes encoding enzymes of the mevalonate pathway resulted in increased lycopene levels. Verifying the subcellular localization of the relevant enzymes revealed that initial metabolic reactions might take place in peroxisomes: despite the absence of a canonical peroxisomal targeting sequence, acetyl-CoA C-acetyltransferase Aat1 localized to peroxisomes. By expressing the plant (+)-valencene synthase CnVS and the basidiomycete sesquiterpenoid synthase Cop6, we succeeded in producing (+)-valencene and α-cuprenene, respectively. Importantly, the fungal compound yielded about tenfold higher titers in comparison to the plant substance. This proof of principle demonstrates that U. maydis can serve as promising novel chassis for the production of terpenoids.
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Affiliation(s)
- Jungho Lee
- Bioeconomy Science Centre, Cluster of Excellence on Plant Sciences, Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Fabienne Hilgers
- Institute for Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, and Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1, Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Anita Loeschke
- Institute for Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, and Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1, Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Karl-Erich Jaeger
- Institute for Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, and Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1, Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Michael Feldbrügge
- Bioeconomy Science Centre, Cluster of Excellence on Plant Sciences, Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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33
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Reindl M, Stock J, Hussnaetter KP, Genc A, Brachmann A, Schipper K. A Novel Factor Essential for Unconventional Secretion of Chitinase Cts1. Front Microbiol 2020; 11:1529. [PMID: 32733418 PMCID: PMC7358432 DOI: 10.3389/fmicb.2020.01529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022] Open
Abstract
Subcellular targeting of proteins is essential to orchestrate cytokinesis in eukaryotic cells. During cell division of Ustilago maydis, for example, chitinases must be specifically targeted to the fragmentation zone at the site of cell division to degrade remnant chitin and thus separate mother and daughter cells. Chitinase Cts1 is exported to this location via an unconventional secretion pathway putatively operating in a lock-type manner. The underlying mechanism is largely unexplored. Here, we applied a forward genetic screen based on UV mutagenesis to identify components essential for Cts1 export. The screen revealed a novel factor termed Jps1 lacking known protein domains. Deletion of the corresponding gene confirmed its essential role for Cts1 secretion. Localization studies demonstrated that Jps1 colocalizes with Cts1 in the fragmentation zone of dividing yeast cells. While loss of Jps1 leads to exclusion of Cts1 from the fragmentation zone and strongly reduced unconventional secretion, deletion of the chitinase does not disturb Jps1 localization. Yeast-two hybrid experiments indicate that the two proteins might interact. In essence, we identified a novel component of unconventional secretion that functions in the fragmentation zone to enable export of Cts1. We hypothesize that Jps1 acts as an anchoring factor for Cts1.
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Affiliation(s)
- Michèle Reindl
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Bioeconomy Science Center, Forschungszentrum Jülich, Jülich, Germany
| | - Janpeter Stock
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Bioeconomy Science Center, Forschungszentrum Jülich, Jülich, Germany
| | - Kai P. Hussnaetter
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Bioeconomy Science Center, Forschungszentrum Jülich, Jülich, Germany
| | - Aycin Genc
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andreas Brachmann
- Genetics, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Kerstin Schipper
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Bioeconomy Science Center, Forschungszentrum Jülich, Jülich, Germany
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34
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Müntjes K, Philipp M, Hüsemann L, Heucken N, Weidtkamp-Peters S, Schipper K, Zurbriggen MD, Feldbrügge M. Establishing Polycistronic Expression in the Model Microorganism Ustilago maydis. Front Microbiol 2020; 11:1384. [PMID: 32670239 PMCID: PMC7326815 DOI: 10.3389/fmicb.2020.01384] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 05/28/2020] [Indexed: 12/16/2022] Open
Abstract
Eukaryotic microorganisms use monocistronic mRNAs to encode proteins. For synthetic biological approaches like metabolic engineering, precise co-expression of several proteins in space and time is advantageous. A straightforward approach is the application of viral 2A peptides to design synthetic polycistronic mRNAs in eukaryotes. During translation of these peptides the ribosome stalls, the peptide chain is released and the ribosome resumes translation. Thus, two independent polypeptide chains can be encoded from a single mRNA when a 2A peptide sequence is placed inbetween the two open reading frames. Here, we establish such a system in the well-studied model microorganism Ustilago maydis. Using two fluorescence reporter proteins, we compared the activity of five viral 2A peptides. Their activity was evaluated in vivo using fluorescence microscopy and validated using fluorescence resonance energy transfer (FRET). Activity ranged from 20 to 100% and the best performing 2A peptide was P2A from porcine teschovirus-1. As proof of principle, we followed regulated gene expression efficiently over time and synthesised a tri-cistronic mRNA encoding biosynthetic enzymes to produce mannosylerythritol lipids (MELs). In essence, we evaluated 2A peptides in vivo and demonstrated the applicability of 2A peptide technology for U. maydis in basic and applied science.
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Affiliation(s)
- Kira Müntjes
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Magnus Philipp
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Lisa Hüsemann
- Institute of Synthetic Biology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Nicole Heucken
- Institute of Synthetic Biology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | | | - Kerstin Schipper
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Matias D. Zurbriggen
- Institute of Synthetic Biology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Bioeconomy Science Centre, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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35
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36
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Renz C, Albanèse V, Tröster V, Albert TK, Santt O, Jacobs SC, Khmelinskii A, Léon S, Ulrich HD. Ubc13-Mms2 cooperates with a family of RING E3 proteins in budding yeast membrane protein sorting. J Cell Sci 2020; 133:jcs.244566. [PMID: 32265276 DOI: 10.1242/jcs.244566] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 03/23/2020] [Indexed: 12/25/2022] Open
Abstract
Polyubiquitin chains linked via lysine (K) 63 play an important role in endocytosis and membrane trafficking. Their primary source is the ubiquitin protein ligase (E3) Rsp5/NEDD4, which acts as a key regulator of membrane protein sorting. The heterodimeric ubiquitin-conjugating enzyme (E2), Ubc13-Mms2, catalyses K63-specific polyubiquitylation in genome maintenance and inflammatory signalling. In budding yeast, the only E3 proteins known to cooperate with Ubc13-Mms2 so far is a nuclear RING finger protein, Rad5, involved in the replication of damaged DNA. Here, we report a contribution of Ubc13-Mms2 to the sorting of membrane proteins to the yeast vacuole via the multivesicular body (MVB) pathway. In this context, Ubc13-Mms2 cooperates with Pib1, a FYVE-RING finger protein associated with internal membranes. Moreover, we identified a family of membrane-associated FYVE-(type)-RING finger proteins as cognate E3 proteins for Ubc13-Mms2 in several species, and genetic analysis indicates that the contribution of Ubc13-Mms2 to membrane trafficking in budding yeast goes beyond its cooperation with Pib1. Thus, our results widely implicate Ubc13-Mms2 as an Rsp5-independent source of K63-linked polyubiquitin chains in the regulation of membrane protein sorting.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Christian Renz
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D-55128 Mainz, Germany
| | - Véronique Albanèse
- Institut Jacques Monod, UMR 7592 Centre National de la Recherche Scientifique/Université Paris-Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France
| | - Vera Tröster
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D-55128 Mainz, Germany
| | - Thomas K Albert
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, D-35043 Marburg, Germany
| | - Olivier Santt
- Cancer Research UK London Research Institute, Clare Hall Laboratories, Blanche Lane, South Mimms EN6 3LD, UK
| | - Susan C Jacobs
- Cancer Research UK London Research Institute, Clare Hall Laboratories, Blanche Lane, South Mimms EN6 3LD, UK
| | - Anton Khmelinskii
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D-55128 Mainz, Germany
| | - Sébastien Léon
- Institut Jacques Monod, UMR 7592 Centre National de la Recherche Scientifique/Université Paris-Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France
| | - Helle D Ulrich
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D-55128 Mainz, Germany
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37
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Hitching a Ride: Mechanics of Transport Initiation through Linker-Mediated Hitchhiking. Biophys J 2020; 118:1357-1369. [PMID: 32061275 DOI: 10.1016/j.bpj.2020.01.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/16/2020] [Accepted: 01/21/2020] [Indexed: 12/14/2022] Open
Abstract
In contrast to the canonical picture of transport by direct attachment to motor proteins, recent evidence shows that a number of intracellular "cargos" navigate the cytoplasm by hitchhiking on motor-driven "carrier" organelles. We describe a quantitative model of intracellular cargo transport via hitchhiking, examining the efficiency of hitchhiking initiation as a function of geometric and mechanical parameters. We focus specifically on the parameter regime relevant to the hitchhiking motion of peroxisome organelles in fungal hyphae. Our work predicts the dependence of transport initiation rates on the distribution of cytoskeletal tracks and carrier organelles, as well as the number, length, and flexibility of the linker proteins that mediate contact between the carrier and the hitchhiking cargo. Furthermore, we demonstrate that attaching organelles to microtubules can result in a substantial enhancement of the hitchhiking initiation rate in tubular geometries such as those found in fungal hyphae. This enhancement is expected to increase the overall transport rate of hitchhiking organelles and lead to greater efficiency in organelle dispersion. Our results leverage a quantitative physical model to highlight the importance of organelle encounter dynamics in noncanonical intracellular transport.
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38
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Pushpalatha KV, Besse F. Local Translation in Axons: When Membraneless RNP Granules Meet Membrane-Bound Organelles. Front Mol Biosci 2019; 6:129. [PMID: 31824961 PMCID: PMC6882739 DOI: 10.3389/fmolb.2019.00129] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/06/2019] [Indexed: 12/14/2022] Open
Abstract
Eukaryotic cell compartmentalization relies on long-known membrane-delimited organelles, as well as on more recently discovered membraneless macromolecular condensates. How these two types of organelles interact to regulate cellular functions is still largely unclear. In this review, we highlight how membraneless ribonucleoprotein (RNP) organelles, enriched in RNAs and associated regulatory proteins, cooperate with membrane-bound organelles for tight spatio-temporal control of gene expression in the axons of neuronal cells. Specifically, we present recent evidence that motile membrane-bound organelles are used as vehicles by RNP cargoes, promoting the long-range transport of mRNA molecules to distal axons. As demonstrated by recent work, membrane-bound organelles also promote local protein synthesis, by serving as platforms for the local translation of mRNAs recruited to their outer surface. Furthermore, dynamic and specific association between RNP cargoes and membrane-bound organelles is mediated by bi-partite adapter molecules that interact with both types of organelles selectively, in a regulated-manner. Maintaining such a dynamic interplay is critical, as alterations in this process are linked to neurodegenerative diseases. Together, emerging studies thus point to the coordination of membrane-bound and membraneless organelles as an organizing principle underlying local cellular responses.
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Affiliation(s)
| | - Florence Besse
- Université Côte d'Azur, CNRS, Inserm, Institut de Biology Valrose, Nice, France
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39
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Qiu R, Zhang J, Xiang X. LIS1 regulates cargo-adapter-mediated activation of dynein by overcoming its autoinhibition in vivo. J Cell Biol 2019; 218:3630-3646. [PMID: 31562232 PMCID: PMC6829669 DOI: 10.1083/jcb.201905178] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/08/2019] [Accepted: 08/29/2019] [Indexed: 02/08/2023] Open
Abstract
Deficiency of the LIS1 protein causes lissencephaly, a brain developmental disorder. Although LIS1 binds the microtubule motor cytoplasmic dynein and has been linked to dynein function in many experimental systems, its mechanism of action remains unclear. Here, we revealed its function in cargo-adapter-mediated dynein activation in the model organism Aspergillus nidulans Specifically, we found that overexpressed cargo adapter HookA (Hook in A. nidulans) missing its cargo-binding domain (ΔC-HookA) causes dynein and its regulator dynactin to relocate from the microtubule plus ends to the minus ends, and this relocation requires LIS1 and its binding protein, NudE. Astonishingly, the requirement for LIS1 or NudE can be bypassed to a significant extent by mutations that prohibit dynein from forming an autoinhibited conformation in which the motor domains of the dynein dimer are held close together. Our results suggest a novel mechanism of LIS1 action that promotes the switch of dynein from the autoinhibited state to an open state to facilitate dynein activation.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, the Uniformed Services University F. Edward Hébert School of Medicine, Bethesda, MD
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40
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Hildebrandt A, Brüggemann M, Rücklé C, Boerner S, Heidelberger JB, Busch A, Hänel H, Voigt A, Möckel MM, Ebersberger S, Scholz A, Dold A, Schmid T, Ebersberger I, Roignant JY, Zarnack K, König J, Beli P. The RNA-binding ubiquitin ligase MKRN1 functions in ribosome-associated quality control of poly(A) translation. Genome Biol 2019; 20:216. [PMID: 31640799 PMCID: PMC6805484 DOI: 10.1186/s13059-019-1814-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 09/04/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Cells have evolved quality control mechanisms to ensure protein homeostasis by detecting and degrading aberrant mRNAs and proteins. A common source of aberrant mRNAs is premature polyadenylation, which can result in non-functional protein products. Translating ribosomes that encounter poly(A) sequences are terminally stalled, followed by ribosome recycling and decay of the truncated nascent polypeptide via ribosome-associated quality control. RESULTS Here, we demonstrate that the conserved RNA-binding E3 ubiquitin ligase Makorin Ring Finger Protein 1 (MKRN1) promotes ribosome stalling at poly(A) sequences during ribosome-associated quality control. We show that MKRN1 directly binds to the cytoplasmic poly(A)-binding protein (PABPC1) and associates with polysomes. MKRN1 is positioned upstream of poly(A) tails in mRNAs in a PABPC1-dependent manner. Ubiquitin remnant profiling and in vitro ubiquitylation assays uncover PABPC1 and ribosomal protein RPS10 as direct ubiquitylation substrates of MKRN1. CONCLUSIONS We propose that MKRN1 mediates the recognition of poly(A) tails to prevent the production of erroneous proteins from prematurely polyadenylated transcripts, thereby maintaining proteome integrity.
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Affiliation(s)
- Andrea Hildebrandt
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Mirko Brüggemann
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, Max-von-Laue-Str. 15, 60438, Frankfurt am Main, Germany
| | - Cornelia Rücklé
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, Max-von-Laue-Str. 15, 60438, Frankfurt am Main, Germany
| | - Susan Boerner
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, Max-von-Laue-Str. 15, 60438, Frankfurt am Main, Germany
| | - Jan B Heidelberger
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Anke Busch
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Heike Hänel
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Andrea Voigt
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Martin M Möckel
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | | | - Anica Scholz
- Faculty of Medicine, Institute of Biochemistry I, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany
| | - Annabelle Dold
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
| | - Tobias Schmid
- Faculty of Medicine, Institute of Biochemistry I, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany
| | - Ingo Ebersberger
- Department for Applied Bioinformatics, Institute of Cell Biology and Neuroscience, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438, Frankfurt am Main, Germany
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Georg-Voigt-Straße 14-16, 60325, Frankfurt am Main, Germany
| | - Jean-Yves Roignant
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Génopode Building, CH-1015, Lausanne, Switzerland
| | - Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, Max-von-Laue-Str. 15, 60438, Frankfurt am Main, Germany.
| | - Julian König
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany.
| | - Petra Beli
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128, Mainz, Germany.
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Liao YC, Fernandopulle MS, Wang G, Choi H, Hao L, Drerup CM, Patel R, Qamar S, Nixon-Abell J, Shen Y, Meadows W, Vendruscolo M, Knowles TPJ, Nelson M, Czekalska MA, Musteikyte G, Gachechiladze MA, Stephens CA, Pasolli HA, Forrest LR, St George-Hyslop P, Lippincott-Schwartz J, Ward ME. RNA Granules Hitchhike on Lysosomes for Long-Distance Transport, Using Annexin A11 as a Molecular Tether. Cell 2019; 179:147-164.e20. [PMID: 31539493 PMCID: PMC6890474 DOI: 10.1016/j.cell.2019.08.050] [Citation(s) in RCA: 276] [Impact Index Per Article: 55.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 05/21/2019] [Accepted: 08/26/2019] [Indexed: 02/06/2023]
Abstract
Long-distance RNA transport enables local protein synthesis at metabolically-active sites distant from the nucleus. This process ensures an appropriate spatial organization of proteins, vital to polarized cells such as neurons. Here, we present a mechanism for RNA transport in which RNA granules "hitchhike" on moving lysosomes. In vitro biophysical modeling, live-cell microscopy, and unbiased proximity labeling proteomics reveal that annexin A11 (ANXA11), an RNA granule-associated phosphoinositide-binding protein, acts as a molecular tether between RNA granules and lysosomes. ANXA11 possesses an N-terminal low complexity domain, facilitating its phase separation into membraneless RNA granules, and a C-terminal membrane binding domain, enabling interactions with lysosomes. RNA granule transport requires ANXA11, and amyotrophic lateral sclerosis (ALS)-associated mutations in ANXA11 impair RNA granule transport by disrupting their interactions with lysosomes. Thus, ANXA11 mediates neuronal RNA transport by tethering RNA granules to actively-transported lysosomes, performing a critical cellular function that is disrupted in ALS.
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Affiliation(s)
| | | | - Guozhen Wang
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0XY, UK
| | - Heejun Choi
- HHMI Janelia Research Campus, Ashburn, VA, USA
| | | | | | | | - Seema Qamar
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0XY, UK
| | - Jonathon Nixon-Abell
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0XY, UK
| | - Yi Shen
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - William Meadows
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0XY, UK
| | | | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK; Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, UK
| | | | | | - Greta Musteikyte
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | | | | | | | | | - Peter St George-Hyslop
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0XY, UK; Department of Medicine (Division of Neurology), University of Toronto and University Health Network, Toronto, Ontario M5S 3H2, Canada
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42
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Rossoll W, Bassell GJ. Crosstalk of Local Translation and Mitochondria: Powering Plasticity in Axons and Dendrites. Neuron 2019; 101:204-206. [PMID: 30653934 DOI: 10.1016/j.neuron.2018.12.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Two papers in Cell uncover reciprocal crosstalk of local translation and mitochondria in neurons. Rangaraju et al. (2019) observe tethered compartments of stable mitochondria in dendrites that provide a local energy supply for mRNA translation at synapses. Cioni et al. (2019) report a novel association of axonal RNA granules with Rab7a-late endosomes that provides a platform for local translation supporting mitochondria.
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Affiliation(s)
- Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA.
| | - Gary J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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43
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Jankowski S, Pohlmann T, Baumann S, Müntjes K, Devan SK, Zander S, Feldbrügge M. The multi PAM2 protein Upa2 functions as novel core component of endosomal mRNA transport. EMBO Rep 2019; 20:e47381. [PMID: 31338952 DOI: 10.15252/embr.201847381] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 06/14/2019] [Accepted: 06/21/2019] [Indexed: 12/28/2022] Open
Abstract
mRNA transport determines spatiotemporal protein expression. Transport units are higher-order ribonucleoprotein complexes containing cargo mRNAs, RNA-binding proteins and accessory proteins. Endosomal mRNA transport in fungal hyphae belongs to the best-studied translocation mechanisms. Although several factors are known, additional core components are missing. Here, we describe the 232 kDa protein Upa2 containing multiple PAM2 motifs (poly[A]-binding protein [Pab1]-associated motif 2) as a novel core component. Loss of Upa2 disturbs transport of cargo mRNAs and associated Pab1. Upa2 is present on almost all transport endosomes in an mRNA-dependent manner. Surprisingly, all four PAM2 motifs are dispensable for function during unipolar hyphal growth. Instead, Upa2 harbours a novel N-terminal effector domain as important functional determinant as well as a C-terminal GWW motif for specific endosomal localisation. In essence, Upa2 meets all the criteria of a novel core component of endosomal mRNA transport and appears to carry out crucial scaffolding functions.
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Affiliation(s)
- Silke Jankowski
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Thomas Pohlmann
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sebastian Baumann
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Kira Müntjes
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Senthil Kumar Devan
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sabrina Zander
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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44
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Core components of endosomal mRNA transport are evolutionarily conserved in fungi. Fungal Genet Biol 2019; 126:12-16. [PMID: 30738139 DOI: 10.1016/j.fgb.2019.01.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 01/31/2019] [Accepted: 01/31/2019] [Indexed: 12/21/2022]
Abstract
Active movement of mRNAs by sophisticated transport machineries determines precise spatiotemporal expression of encoded proteins. A prominent example discovered in fungi is microtubule-dependent transport via endosomes. This mode of transport was thought to be only operational in the basidiomycete Ustilago maydis. Here, we report that distinct core components are evolutionarily conserved in fungal species of distantly related phyla like Mucoromycota. Interestingly, orthologues of the key RNA-binding protein Rrm4 from the higher basidiomycete Coprinopsis cinerea and the mucoromycete Rhizophagus irregularis shuttle on endosomes in hyphae of U. maydis. Thus, endosomal mRNA transport appears to be more wide-spread than initially anticipated.
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45
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Cioni JM, Lin JQ, Holtermann AV, Koppers M, Jakobs MAH, Azizi A, Turner-Bridger B, Shigeoka T, Franze K, Harris WA, Holt CE. Late Endosomes Act as mRNA Translation Platforms and Sustain Mitochondria in Axons. Cell 2019; 176:56-72.e15. [PMID: 30612743 PMCID: PMC6333918 DOI: 10.1016/j.cell.2018.11.030] [Citation(s) in RCA: 248] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 09/10/2018] [Accepted: 11/18/2018] [Indexed: 12/14/2022]
Abstract
Local translation regulates the axonal proteome, playing an important role in neuronal wiring and axon maintenance. How axonal mRNAs are localized to specific subcellular sites for translation, however, is not understood. Here we report that RNA granules associate with endosomes along the axons of retinal ganglion cells. RNA-bearing Rab7a late endosomes also associate with ribosomes, and real-time translation imaging reveals that they are sites of local protein synthesis. We show that RNA-bearing late endosomes often pause on mitochondria and that mRNAs encoding proteins for mitochondrial function are translated on Rab7a endosomes. Disruption of Rab7a function with Rab7a mutants, including those associated with Charcot-Marie-Tooth type 2B neuropathy, markedly decreases axonal protein synthesis, impairs mitochondrial function, and compromises axonal viability. Our findings thus reveal that late endosomes interact with RNA granules, translation machinery, and mitochondria and suggest that they serve as sites for regulating the supply of nascent pro-survival proteins in axons. Ribonucleoprotein particles are associated with endosomes in axons Rab7a endosomes provide sites for axonal local translation Rab7a endosomes support axonal synthesis of survival factors CMT2B-Rab7a mutations affect axonal translation and mitochondrial integrity
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Affiliation(s)
- Jean-Michel Cioni
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Julie Qiaojin Lin
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Anne V Holtermann
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Max Koppers
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Maximilian A H Jakobs
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Afnan Azizi
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Benita Turner-Bridger
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Toshiaki Shigeoka
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - William A Harris
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK.
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46
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Olgeiser L, Haag C, Boerner S, Ule J, Busch A, Koepke J, König J, Feldbrügge M, Zarnack K. The key protein of endosomal mRNP transport Rrm4 binds translational landmark sites of cargo mRNAs. EMBO Rep 2018; 20:embr.201846588. [PMID: 30552148 DOI: 10.15252/embr.201846588] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 11/09/2018] [Accepted: 11/09/2018] [Indexed: 01/09/2023] Open
Abstract
RNA-binding proteins (RBPs) determine spatiotemporal gene expression by mediating active transport and local translation of cargo mRNAs. Here, we cast a transcriptome-wide view on the transported mRNAs and cognate RBP binding sites during endosomal messenger ribonucleoprotein (mRNP) transport in Ustilago maydis Using individual-nucleotide resolution UV crosslinking and immunoprecipitation (iCLIP), we compare the key transport RBP Rrm4 and the newly identified endosomal mRNP component Grp1 that is crucial to coordinate hyphal growth. Both RBPs bind predominantly in the 3' untranslated region of thousands of shared cargo mRNAs, often in close proximity. Intriguingly, Rrm4 precisely binds at stop codons, which constitute landmark sites of translation, suggesting an intimate connection of mRNA transport and translation. Towards uncovering the code of recognition, we identify UAUG as specific binding motif of Rrm4 that is bound by its third RRM domain. Altogether, we provide first insights into the positional organisation of co-localising RBPs on individual cargo mRNAs.
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Affiliation(s)
- Lilli Olgeiser
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Carl Haag
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Susan Boerner
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jernej Ule
- The Francis Crick Institute, London, UK.,Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | - Anke Busch
- Institute of Molecular Biology gGmbH, Mainz, Germany
| | - Janine Koepke
- Medical Clinic II (Molecular Pneumology), Excellence Cluster Cardio-Pulmonary System, Justus Liebig University of Gießen, Gießen, Germany
| | - Julian König
- Institute of Molecular Biology gGmbH, Mainz, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Frankfurt am Main, Germany
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47
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Béthune J, Jansen RP, Feldbrügge M, Zarnack K. Membrane-Associated RNA-Binding Proteins Orchestrate Organelle-Coupled Translation. Trends Cell Biol 2018; 29:178-188. [PMID: 30455121 DOI: 10.1016/j.tcb.2018.10.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 10/28/2018] [Accepted: 10/29/2018] [Indexed: 02/02/2023]
Abstract
Proteins are positioned and act at defined subcellular locations. This is particularly important in eukaryotic cells that deliver proteins to membrane-bound organelles such as the endoplasmic reticulum (ER), mitochondria, or endosomes. It is axiomatic that organelle targeting depends mainly on polypeptide signals. However, recent results demonstrate that targeting elements within the encoding transcripts are essential for efficient protein localisation. Key readers of these elements are membrane-associated RNA-binding proteins (memRBPs) that orchestrate organelle-coupled translation. The translation products then either cross the membrane for organelle entry or hitchhike on organelle surfaces for complex assembly and co-transport. Understanding the interaction of protein- and RNA-based targeting signals is essential to decipher the molecular basis for mutant phenotypes in disease.
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Affiliation(s)
- Julien Béthune
- Heidelberg University, Biochemistry Center, Cluster of Excellence CellNetworks, 69120 Heidelberg, Germany
| | - Ralf-Peter Jansen
- Eberhard-Karls-University Tübingen, Interfaculty Institute of Biochemistry, Hoppe-Seyler-Straße 4, 72076 Tübingen, Germany
| | - Michael Feldbrügge
- Heinrich-Heine University Düsseldorf, Institute for Microbiology, Cluster of Excellence on Plant Sciences, 40204 Düsseldorf, Germany.
| | - Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany.
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48
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Yang Y, Chou HL, Crofts AJ, Zhang L, Tian L, Washida H, Fukuda M, Kumamaru T, Oviedo OJ, Starkenburg SR, Okita TW. Selective sets of mRNAs localize to extracellular paramural bodies in a rice glup6 mutant. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:5045-5058. [PMID: 30102323 PMCID: PMC6189835 DOI: 10.1093/jxb/ery297] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 08/07/2018] [Indexed: 05/18/2023]
Abstract
The transport of rice glutelin storage proteins to the storage vacuoles requires the Rab5 GTPase and its related guanine nucleotide exchange factor (Rab5-GEF). Loss of function of these membrane vesicular trafficking factors results in the initial secretion of storage proteins and later their partial engulfment by the plasma membrane to form an extracellular paramural body (PMB), an aborted endosome complex. Here, we show that in the rice Rab5-GEF mutant glup6, glutelin RNAs are specifically mislocalized from their normal location on the cisternal endoplasmic reticulum (ER) to the protein body-ER, and are also apparently translocated to the PMBs. We substantiated the association of mRNAs with this aborted endosome complex by RNA-seq of PMBs purified by flow cytometry. Two PMB-associated groups of RNA were readily resolved: those that were specifically enriched in this aborted complex and those that were highly expressed in the cytoplasm. Examination of the PMB-enriched RNAs indicated that they were not a random sampling of the glup6 transcriptome but, instead, encompassed only a few functional mRNA classes. Although specific autophagy is also an alternative mechanism, our results support the view that RNA localization may co-opt membrane vesicular trafficking, and that many RNAs that share function or intracellular location are co-transported in developing rice seeds.
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Affiliation(s)
- Yongil Yang
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
- Present address: Institute of Agriculture, The University of Tennessee, Knoxville, TN 37996, USA
| | - Hong-Li Chou
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
- Present address: The Huck Institutes of the Life Sciences, Pennsylvania State University, PA 16802, USA
| | - Andrew J Crofts
- International Liberal Arts Program, Akita International University, Akita, Japan
| | - Laining Zhang
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
| | - Li Tian
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
| | - Haruhiko Washida
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
- Present Address: Organic Nico Co., Ltd, North #205, Kyodai Katsura Venture Plaza, 1–36, Goryo-Ohara, Nishikyo-ku, Kyoto 615–8245, Japan
| | - Masako Fukuda
- Faculty of Agriculture, Kyushu University, Motooka Nishi-ku, Fukuoka, Japan
| | - Toshihiro Kumamaru
- Faculty of Agriculture, Kyushu University, Motooka Nishi-ku, Fukuoka, Japan
| | | | | | - Thomas W Okita
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
- Correspondence:
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Zuo H, Yang L, Zheng J, Su Z, Weng S, He J, Xu X. A single C4 Zinc finger-containing protein from Litopenaeus vannamei involved in antibacterial responses. FISH & SHELLFISH IMMUNOLOGY 2018; 81:493-501. [PMID: 30064017 DOI: 10.1016/j.fsi.2018.07.053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 07/18/2018] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
The Zinc finger domains (ZnFs), which contain finger-like protrusions stabilized by zinc ions and function to bind DNA, RNA, protein and lipid substrates, are ubiquitously present in a large number of proteins. In this study, a novel protein containing a single C4 type Znf domain (SZnf) was identified from Pacific white shrimp, Litopenaeus vannamei and its role in immunity was further investigated. The ZnF domain of SZnF but not other regions shared high homology with those of fushi tarazu-factor 1 (FTZ-F1) proteins. The SZnF protein was mainly localized in the cytoplasm and was also present in the nucleus at a small level. SZnF was high expressed in the scape and muscle tissues of healthy shrimp and its expression in gill and heptopancreas was strongly up-regulated during bacterial infection. Silencing of SZnf in vivo could strongly increase the susceptibility of shrimp to infection with Vibrio parahaemolyticus but not white spot syndrome virus (WSSV), suggesting that SZnf could be mainly involved in antibacterial responses. Both dual luciferase reporter assays and real-time PCR analysis demonstrated that SZnf could positively regulate the expression of various antimicrobial peptides in vitro and in vivo, which could be part of the mechanism underlying its antibacterial effects. In summary, the current study could help learn more about the function of ZnF-containing proteins and the regulatory mechanisms of immune responses against pathogen infection in crustaceans.
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Affiliation(s)
- Hongliang Zuo
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Linwei Yang
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Jiefu Zheng
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Ziqi Su
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Shaoping Weng
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China
| | - Jianguo He
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China.
| | - Xiaopeng Xu
- MOE Key Laboratory of Aquatic Product Safety/State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, PR China; Institute of Aquatic Economic Animals and Guangdong Provice Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, Guangzhou, PR China.
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50
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Luo KR, Huang NC, Yu TS. Selective Targeting of Mobile mRNAs to Plasmodesmata for Cell-to-Cell Movement. PLANT PHYSIOLOGY 2018; 177:604-614. [PMID: 29581179 PMCID: PMC6001314 DOI: 10.1104/pp.18.00107] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 03/13/2018] [Indexed: 05/20/2023]
Abstract
Many plant mRNAs move from cell to cell or long distance to execute non-cell-autonomous functions. These mobile mRNAs traffic through the phloem to regulate many developmental processes, but despite the burgeoning discovery of mobile mRNAs, little is known about the mechanism underlying the intracellular sorting of these mRNAs. Here, we exploited a fluorescence-based mRNA labeling system, using the bacteriophage coat protein MS2, fused to GFP (MS2-GFP) and an MS2 recognition site in the RNA of interest, to visualize the intracellular trafficking of mobile mRNAs in living plant cells of Nicotiana benthamiana We first improved this system by using the nuclear localization sequence from FD, which substantially reduced the fluorescent background of MS2-GFP in the cytoplasm. The modified system allowed us to observe the cytoplasmic fluorescent foci dependent on MS2-binding sites. Coexpressing the MS2-GFP system with a virus movement protein, which is a plasmodesmata (PD)-localized nonspecific RNA-binding protein, targeted cytoplasmic fluorescent foci to the PD, suggesting that the cytoplasmic fluorescent foci contain mRNA and MS2-GFP. Our ex vivo RNA imaging revealed that mobile but not nonmobile mRNAs were selectively targeted to PD. Real-time images of intracellular translocation revealed that the translocation of mRNA and organelles in the transvacuolar strands may be governed by the same mechanism. Our study suggests that PD targeting of mRNA is a selective step in determining mRNA cell-to-cell movement of mRNAs.
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Affiliation(s)
- Kai-Ren Luo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Nien-Chen Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Tien-Shin Yu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
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