scholarly journals RNA helicase DDX6 in P-bodies is essential for the assembly of stress granules

2021 ◽  
Author(s):  
Vladimir Majerciak ◽  
Tongqing Zhou ◽  
Zhi-Ming Zheng
Keyword(s):  
Rna Processing ◽  
Stress Granules ◽  
The Other ◽  
Helicase Activity ◽  
Dual Roles ◽  
Processing Bodies ◽  
P Bodies ◽  
Rna Granules ◽  
Cytoplasmic Rna ◽  
Conceptual Advance

Two prominent cytoplasmic RNA granules, ubiquitous RNA-processing bodies (PB) and inducible stress granules (SG), regulate storage of translationally arrested mRNAs and are intimately related. In this study, we found the dependence of SG formation on PB in the cells under arsenite (ARS) stress, but not the other way around. GW182, 4E-T and DDX6 essential for PB formation differentially affect SG formation in the cells under ARS stress, with DDX6 being the most prominent. The cells with DDX6 deficiency display irregular shape of SG which could be rescued by ectopic wt DDX6, but not its helicase mutant E247A DDX6, which induces SG in the cells without stress, indicating that DDX6 helicase activity is essential for PB, but suppressive for SG. DDX6's dual roles are independent of DDX6 interactors EDC3, CNOT1, and PAT1B. This study provides a conceptual advance of how DDX6 involves in the biogenesis of PB and SG.

scholarly journals Edc3p and a glutamine/asparagine-rich domain of Lsm4p function in processing body assembly in Saccharomyces cerevisiae

2007 ◽  
Vol 179 (3) ◽  
pp. 437-449 ◽  
Author(s):  
Carolyn J. Decker ◽  
Daniela Teixeira ◽  
Roy Parker
Keyword(s):  
Protein Interactions ◽  
Messenger Rna ◽  
Mrna Decay ◽  
Processing Bodies ◽  
P Bodies ◽  
Rna Granules ◽  
Rich Domain ◽  
Cytoplasmic Rna ◽  
Processing Body ◽  
The Individual

Processing bodies (P-bodies) are cytoplasmic RNA granules that contain translationally repressed messenger ribonucleoproteins (mRNPs) and messenger RNA (mRNA) decay factors. The physical interactions that form the individual mRNPs within P-bodies and how those mRNPs assemble into larger P-bodies are unresolved. We identify direct protein interactions that could contribute to the formation of an mRNP complex that consists of core P-body components. Additionally, we demonstrate that the formation of P-bodies that are visible by light microscopy occurs either through Edc3p, which acts as a scaffold and cross-bridging protein, or via the “prionlike” domain in Lsm4p. Analysis of cells defective in P-body formation indicates that the concentration of translationally repressed mRNPs and decay factors into microscopically visible P-bodies is not necessary for basal control of translation repression and mRNA decay. These results suggest a stepwise model for P-body assembly with the initial formation of a core mRNA–protein complex that then aggregates through multiple specific mechanisms.

scholarly journals Stress induces the assembly of RNA granules in the chloroplast of Chlamydomonas reinhardtii

2008 ◽  
Vol 182 (4) ◽  
pp. 641-646 ◽  
Author(s):  
James Uniacke ◽  
William Zerges
Keyword(s):  
Oxidative Stress ◽  
Chlamydomonas Reinhardtii ◽  
Large Subunit ◽  
Ribosomal Subunit ◽  
Stress Granules ◽  
Mrna Localization ◽  
Messenger Rnas ◽  
Rna Granules ◽  
Cytoplasmic Rna ◽  
Ribulosebisphosphate Carboxylase

Eukaryotic cells under stress repress translation and localize these messenger RNAs (mRNAs) to cytoplasmic RNA granules. We show that specific stress stimuli induce the assembly of RNA granules in an organelle with bacterial ancestry, the chloroplast of Chlamydomonas reinhardtii. These chloroplast stress granules (cpSGs) form during oxidative stress and disassemble during recovery from stress. Like mammalian stress granules, cpSGs contain poly(A)-binding protein and the small, but not the large, ribosomal subunit. In addition, mRNAs are in continuous flux between polysomes and cpSGs during stress. Localization of cpSGs within the pyrenoid reveals that this chloroplast compartment functions in this stress response. The large subunit of ribulosebisphosphate carboxylase/oxygenase also assembles into cpSGs and is known to bind mRNAs during oxidative stress, raising the possibility that it plays a role in cpSG assembly. This discovery within such an organelle suggests that mRNA localization to granules during stress is a more general phenomenon than currently realized.

scholarly journals Stress granules and RNA processing bodies are novel autoantibody targets in systemic sclerosis

2016 ◽  
Vol 18 (1) ◽  
Author(s):  
Michael E. Johnson ◽  
Andrew V. Grassetti ◽  
Jaclyn N. Taroni ◽  
Shawn M. Lyons ◽  
Devin Schweppe ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Rna Processing ◽  
Stress Granules ◽  
Processing Bodies

RNA granules and cytoskeletal links

2014 ◽  
Vol 42 (4) ◽  
pp. 1206-1210 ◽  
Author(s):  
Dipen Rajgor ◽  
Catherine M. Shanahan
Keyword(s):  
Mammalian Cells ◽  
Dynamic Properties ◽  
Translational Repression ◽  
Processing Bodies ◽  
P Bodies ◽  
Rna Granules ◽  
Messenger Ribonucleoprotein ◽  
Cytoskeletal Networks ◽  
And Control ◽  
Lower Eukaryote

In eukaryotic cells, non-translating mRNAs can accumulate into cytoplasmic mRNP (messenger ribonucleoprotein) granules such as P-bodies (processing bodies) and SGs (stress granules). P-bodies contain the mRNA decay and translational repression machineries and are ubiquitously expressed in mammalian cells and lower eukaryote species including Saccharomyces cerevisiae, Drosophila melanogaster and Caenorhabditis elegans. In contrast, SGs are only detected during cellular stress when translation is inhibited and form from aggregates of stalled pre-initiation complexes. SGs and P-bodies are related to NGs (neuronal granules), which are essential in the localization and control of mRNAs in neurons. Importantly, RNA granules are linked to the cytoskeleton, which plays an important role in mediating many of their dynamic properties. In the present review, we discuss how P-bodies, SGs and NGs are linked to cytoskeletal networks and the importance of these linkages in maintaining localization of their RNA cargoes.

scholarly journals Poly(A) binding protein is required for mRNP remodeling to form P-bodies in mammalian cells

2021 ◽  
Author(s):  
Jingwei Xie ◽  
Yu Chen ◽  
Xiaoyu Wei ◽  
Guennadi Kozlov
Keyword(s):  
Mammalian Cells ◽  
Binding Protein ◽  
Stress Granules ◽  
Body Formation ◽  
P Bodies ◽  
Rna Granules ◽  
Cellular Processes ◽  
Early Stages ◽  
Summary Statement

AbstractCompartmentalization of mRNA through formation of RNA granules is involved in many cellular processes, yet it is not well understood. mRNP complexes undergo dramatic changes in protein compositions, reflected by markers of P-bodies and stress granules. Here, we show that PABPC1, albeit absent in P-bodies, plays important role in P-body formation. Depletion of PABPC1 decreases P-body population in unstressed cells. Upon stress in PABPC1 depleted cells, individual P-bodies fail to form and instead P-body proteins assemble on PABPC1-containing stress granules. We hypothesize that mRNP recruit proteins via PABPC1 to assemble P-bodies, before PABPC1 is displaced from mRNP. Further, we demonstrate that GW182 can mediate P-body assembly. These findings help us understand the early stages of mRNP remodeling and P-body formation.Summary statementA novel role of poly(A) binding protein is reported in P-body formation

scholarly journals RNA processing bodies are disassembled during Old World alphavirus infection

2019 ◽  
Vol 100 (10) ◽  
pp. 1375-1389 ◽  
Author(s):  
Lifeng Liu ◽  
Eva Weiss ◽  
Marc D. Panas ◽  
Benjamin Götte ◽  
Stina Sellberg ◽  
...  
Keyword(s):  
Rna Processing ◽  
Nuclear Import ◽  
Semliki Forest Virus ◽  
Early Stage ◽  
Processing Bodies ◽  
Old World ◽  
P Bodies ◽  
Infected Cells ◽  
As Stress ◽  
Alphavirus Infection

RNA processing bodies (P-bodies) are non-membranous cytoplasmic aggregates of mRNA and proteins involved in mRNA decay and translation repression. P-bodies actively respond to environmental stresses, associated with another type of RNA granules, known as stress granules (SGs). Alphaviruses were previously shown to block SG induction at late stages of infection, which is important for efficient viral growth. In this study, we found that P-bodies were disassembled or reduced in number very early in infection with Semliki Forest virus (SFV) or chikungunya virus (CHIKV) in a panel of cell lines. Similar to SGs, reinduction of P-bodies by a second stress (sodium arsenite) was also blocked in infected cells. The disassembly of P-bodies still occurred in non-phosphorylatable eIF2α mouse embryonal fibroblasts (MEFs) that are impaired in SG assembly. Studies of translation status by ribopuromycylation showed that P-body disassembly is independent of host translation shutoff, which requires the phosphorylation of eIF2α in the SFV- or CHIKV-infected cells. Labelling of newly synthesized RNA with bromo-UTP showed that host transcription shutoff correlated with P-body disassembly at the same early stage (3–4 h) after infection. However, inhibition of global transcription with actinomycin D (ActD) failed to disassemble P-bodies as effectively as the viruses did. Interestingly, blocking nuclear import with importazole led to an efficient P-bodies loss. Our data reveal that P-bodies are disassembled independently from SG formation at early stages of Old World alphavirus infection and that nuclear import is involved in the dynamic of P-bodies.

scholarly journals KSHV RNA-binding protein ORF57 inhibits P-body formation to promote viral multiplication by interaction with Ago2 and GW182

2019 ◽  
Vol 47 (17) ◽  
pp. 9368-9385 ◽  
Author(s):  
Nishi R Sharma ◽  
Vladimir Majerciak ◽  
Michael J Kruhlak ◽  
Lulu Yu ◽  
Jeong Gu Kang ◽  
...  
Keyword(s):  
Rna Binding ◽  
Binding Protein ◽  
Rna Binding Protein ◽  
Time Lapse ◽  
Processing Bodies ◽  
P Bodies ◽  
Rna Granules ◽  
Inhibitory Function ◽  
Invasion Mechanisms ◽  
Initial Stage

Abstract Cellular non-membranous RNA-granules, P-bodies (RNA processing bodies, PB) and stress granules (SG), are important components of the innate immune response to virus invasion. Mechanisms governing how a virus modulates PB formation remain elusive. Here, we report the important roles of GW182 and DDX6, but not Dicer, Ago2 and DCP1A, in PB formation, and that Kaposi’s sarcoma-associated herpesvirus (KSHV) lytic infection reduces PB formation through several specific interactions with viral RNA-binding protein ORF57. The wild-type ORF57, but not its N-terminal dysfunctional mutant, inhibits PB formation by interacting with the N-terminal GW-domain of GW182 and the N-terminal domain of Ago2, two major components of PB. KSHV ORF57 also induces nuclear Ago2 speckles. Homologous HSV-1 ICP27, but not EBV EB2, shares this conserved inhibitory function with KSHV ORF57. By using time-lapse confocal microscopy of HeLa cells co-expressing GFP-tagged GW182, we demonstrated that viral ORF57 inhibits primarily the scaffolding of GW182 at the initial stage of PB formation. Consistently, KSHV-infected iSLK/Bac16 cells with reduced GW182 expression produced far fewer PB and SG, but 100-fold higher titer of infectious KSHV virions when compared to cells with normal GW182 expression. Altogether, our data provide the first evidence that a DNA virus evades host innate immunity by encoding an RNA-binding protein that promotes its replication by blocking PB formation.

Endoplasmic reticulum contact sites regulate the dynamics of membraneless organelles

Science ◽  
2020 ◽  
Vol 367 (6477) ◽  
pp. eaay7108 ◽  
Author(s):  
Jason E. Lee ◽  
Peter I. Cathey ◽  
Haoxi Wu ◽  
Roy Parker ◽  
Gia K. Voeltz
Keyword(s):  
Endoplasmic Reticulum ◽  
Stress Granules ◽  
Human Cells ◽  
Stress Granule ◽  
Processing Bodies ◽  
P Bodies ◽  
Contact Sites ◽  
Membrane Bound ◽  
Efficient Transfer ◽  
Er Membrane

Tethered interactions between the endoplasmic reticulum (ER) and other membrane-bound organelles allow for efficient transfer of ions and/or macromolecules and provide a platform for organelle fission. Here, we describe an unconventional interface between membraneless ribonucleoprotein granules, such as processing bodies (P-bodies, or PBs) and stress granules, and the ER membrane. We found that PBs are tethered at molecular distances to the ER in human cells in a tunable fashion. ER-PB contact and PB biogenesis were modulated by altering PB composition, ER shape, or ER translational capacity. Furthermore, ER contact sites defined the position where PB and stress granule fission occurs. We thus suggest that the ER plays a fundamental role in regulating the assembly and disassembly of membraneless organelles.

scholarly journals The yeast Cbk1 kinase regulates mRNA localization via the mRNA-binding protein Ssd1

2011 ◽  
Vol 192 (4) ◽  
pp. 583-598 ◽  
Author(s):  
Cornelia Kurischko ◽  
Hong Kyung Kim ◽  
Venkata K. Kuravi ◽  
Juliane Pratzka ◽  
Francis C. Luca
Keyword(s):  
Binding Protein ◽  
Cellular Stress ◽  
Stress Granules ◽  
Polarized Growth ◽  
Cell Integrity ◽  
Processing Bodies ◽  
P Bodies ◽  
Mrna Binding Protein ◽  
Cortical Localization ◽  
Mrna Binding

The mRNA-binding protein Ssd1 is a substrate for the Saccharomyces cerevisiae LATS/NDR orthologue Cbk1, which controls polarized growth, cell separation, and cell integrity. We discovered that most Ssd1 localizes diffusely within the cytoplasm, but some transiently accumulates at sites of polarized growth. Cbk1 inhibition and cellular stress cause Ssd1 to redistribute to mRNA processing bodies (P-bodies) and stress granules, which are known to repress translation. Ssd1 recruitment to P-bodies is independent of mRNA binding and is promoted by the removal of Cbk1 phosphorylation sites. SSD1 deletion severely impairs the asymmetric localization of the Ssd1-associated mRNA, SRL1. Expression of phosphomimetic Ssd1 promotes polarized localization of SRL1 mRNA, whereas phosphorylation-deficient Ssd1 causes constitutive localization of SRL1 mRNA to P-bodies and causes cellular lysis. These data support the model that Cbk1-mediated phosphorylation of Ssd1 promotes the cortical localization of Ssd1–mRNA complexes, whereas Cbk1 inhibition, cellular stress, and Ssd1 dephosphorylation promote Ssd1–mRNA interactions with P-bodies and stress granules, leading to translational repression.

scholarly journals P bodies promote stress granule assembly in Saccharomyces cerevisiae

2008 ◽  
Vol 183 (3) ◽  
pp. 441-455 ◽  
Author(s):  
J. Ross Buchan ◽  
Denise Muhlrad ◽  
Roy Parker
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mammalian Cells ◽  
Protein Composition ◽  
Stress Granules ◽  
Glucose Deprivation ◽  
Stress Granule ◽  
Granule Formation ◽  
P Bodies ◽  
Rna Granules ◽  
Kinetics Of

Recent results indicate that nontranslating mRNAs in eukaryotic cells exist in distinct biochemical states that accumulate in P bodies and stress granules, although the nature of interactions between these particles is unknown. We demonstrate in Saccharomyces cerevisiae that RNA granules with similar protein composition and assembly mechanisms as mammalian stress granules form during glucose deprivation. Stress granule assembly is dependent on P-body formation, whereas P-body assembly is independent of stress granule formation. This suggests that stress granules primarily form from mRNPs in preexisting P bodies, which is also supported by the kinetics of P-body and stress granule formation both in yeast and mammalian cells. These observations argue that P bodies are important sites for decisions of mRNA fate and that stress granules, at least in yeast, primarily represent pools of mRNAs stalled in the process of reentry into translation from P bodies.

Sign in / Sign up

Export Citation Format

Share Document