scholarly journals Maternal mRNAs are regulated by diverse P body–related mRNP granules during early Caenorhabditis elegans development

2008 ◽  
Vol 182 (3) ◽  
pp. 559-572 ◽  
Author(s):  
Scott L. Noble ◽  
Brittany L. Allen ◽  
Lai Kuan Goh ◽  
Kristen Nordick ◽  
Thomas C. Evans
Keyword(s):  
Caenorhabditis Elegans ◽  
Rna Binding ◽  
Germ Line ◽  
Processing Bodies ◽  
Body Protein ◽  
P Bodies ◽  
Granule Morphology ◽  
Maternal Mrnas ◽  
Rnp Granules

Processing bodies (P bodies) are conserved mRNA–protein (mRNP) granules that are thought to be cytoplasmic centers for mRNA repression and degradation. However, their specific functions in vivo remain poorly understood. We find that repressed maternal mRNAs and their regulators localize to P body–like mRNP granules in the Caenorhabditis elegans germ line. Surprisingly, several distinct types of regulated granules form during oocyte and embryo development. 3′ untranslated region elements direct mRNA targeting to one of these granule classes. The P body factor CAR-1/Rap55 promotes association of repressed mRNA with granules and contributes to repression of Notch/glp-1 mRNA. However, CAR-1 controls Notch/glp-1 only during late oogenesis, where it functions with the RNA-binding regulators PUF-5, PUF-6, and PUF-7. The P body protein CGH-1/Rck/Dhh1 differs from CAR-1 in control of granule morphology and promotes mRNP stability in arrested oocytes. Therefore, a system of diverse and regulated RNP granules elicits stage-specific functions that ensure proper mRNA control during early development.

scholarly journals Protection of specific maternal messenger RNAs by the P body protein CGH-1 (Dhh1/RCK) during Caenorhabditis elegans oogenesis

2008 ◽  
Vol 182 (3) ◽  
pp. 543-557 ◽  
Author(s):  
Peter R. Boag ◽  
Arzu Atalay ◽  
Stacey Robida ◽  
Valerie Reinke ◽  
T. Keith Blackwell
Keyword(s):  
Caenorhabditis Elegans ◽  
Messenger Rnas ◽  
Processing Bodies ◽  
Body Protein ◽  
Translation Inhibition ◽  
Mrna Decapping ◽  
P Bodies ◽  
Somatic Tissues ◽  
Translational Regulators ◽  
Dependent Mechanism

During oogenesis, numerous messenger RNAs (mRNAs) are maintained in a translationally silenced state. In eukaryotic cells, various translation inhibition and mRNA degradation mechanisms congregate in cytoplasmic processing bodies (P bodies). The P body protein Dhh1 inhibits translation and promotes decapping-mediated mRNA decay together with Pat1 in yeast, and has been implicated in mRNA storage in metazoan oocytes. Here, we have investigated in Caenorhabditis elegans whether Dhh1 and Pat1 generally function together, and how they influence mRNA sequestration during oogenesis. We show that in somatic tissues, the Dhh1 orthologue (CGH-1) forms Pat1 (patr-1)-dependent P bodies that are involved in mRNA decapping. In contrast, during oogenesis, CGH-1 forms patr-1–independent mRNA storage bodies. CGH-1 then associates with translational regulators and a specific set of maternal mRNAs, and prevents those mRNAs from being degraded. Our results identify somatic and germ cell CGH-1 functions that are distinguished by the involvement of PATR-1, and reveal that during oogenesis, numerous translationally regulated mRNAs are specifically protected by a CGH-1–dependent mechanism.

scholarly journals Syncrip/hnRNP Q is required for activity-induced Msp300/Nesprin-1 expression and new synapse formation

2020 ◽  
Vol 219 (3) ◽  
Author(s):  
Joshua Titlow ◽  
Francesca Robertson ◽  
Aino Järvelin ◽  
David Ish-Horowicz ◽  
Carlas Smith ◽  
...  
Keyword(s):  
Single Molecule ◽  
Posttranscriptional Regulation ◽  
Rna Binding ◽  
Synapse Formation ◽  
Long Distance ◽  
Key Factor ◽  
Larval Neuromuscular Junction ◽  
Rnp Granules ◽  
Activity Dependent

Memory and learning involve activity-driven expression of proteins and cytoskeletal reorganization at new synapses, requiring posttranscriptional regulation of localized mRNA a long distance from corresponding nuclei. A key factor expressed early in synapse formation is Msp300/Nesprin-1, which organizes actin filaments around the new synapse. How Msp300 expression is regulated during synaptic plasticity is poorly understood. Here, we show that activity-dependent accumulation of Msp300 in the postsynaptic compartment of the Drosophila larval neuromuscular junction is regulated by the conserved RNA binding protein Syncrip/hnRNP Q. Syncrip (Syp) binds to msp300 transcripts and is essential for plasticity. Single-molecule imaging shows that msp300 is associated with Syp in vivo and forms ribosome-rich granules that contain the translation factor eIF4E. Elevated neural activity alters the dynamics of Syp and the number of msp300:Syp:eIF4E RNP granules at the synapse, suggesting that these particles facilitate translation. These results introduce Syp as an important early acting activity-dependent regulator of a plasticity gene that is strongly associated with human ataxias.

scholarly journals The arrested state of processing bodies supports mRNA regulation in early development

2021 ◽  
Author(s):  
M. Sankaranarayanan ◽  
Ryan J. Emenecker ◽  
Marcus Jahnel ◽  
Irmela R. E. A. Trussina ◽  
Matt Wayland ◽  
...  
Keyword(s):  
Physical Properties ◽  
Electrostatic Interactions ◽  
Processing Bodies ◽  
P Bodies ◽  
Intrinsically Disordered ◽  
Intrinsically Disordered Regions ◽  
Dead Box ◽  
Premature Release ◽  
Liquid Liquid Phase Separation

ABSTRACTBiomolecular condensates that form via liquid-liquid phase separation can exhibit diverse physical states. Despite considerable progress, the relevance of condensate physical states forin vivobiological function remains limited. Here, we investigated the physical properties ofin vivoprocessing bodies (P bodies) and their impact on mRNA storage in matureDrosophilaoocytes. We show that the conserved DEAD-box RNA helicase Me31B forms P body condensates which adopt a less dynamic, arrested physical state. We demonstrate that structurally distinct proteins and hydrophobic and electrostatic interactions, together with RNA and intrinsically disordered regions, regulate the physical properties of P bodies. Finally, using live imaging, we show that the arrested state of P bodies is required to prevent the premature release ofbicoid(bcd) mRNA, a body axis determinant, and that P body dissolution leads tobcdrelease. Together, this work establishes a role for arrested states of biomolecular condensates in regulating cellular function in a developing organism.

Roles for myosin Va in RNA transport and turnover

2012 ◽  
Vol 40 (6) ◽  
pp. 1416-1420 ◽  
Author(s):  
Mary W. McCaffrey ◽  
Andrew J. Lindsay
Keyword(s):  
Rna Binding ◽  
Rna Binding Proteins ◽  
Class V ◽  
Processing Bodies ◽  
Surface Receptors ◽  
P Bodies ◽  
Myosin Va ◽  
Myosin Vb ◽  
Actin Cables ◽  
The Brain

Mammals express three class V myosins. Myosin Va is widely expressed, but enriched in the brain, testes and melanocytes, myosin Vb is expressed ubiquitously, and myosin Vc is believed to be epithelium-specific. Myosin Va is the best characterized of the three and plays a key role in the transport of cargo to the plasma membrane. Its cargo includes cell-surface receptors, pigment and organelles such as the endoplasmic reticulum. It is also emerging that RNA and RNA-BPs (RNA-binding proteins) make up another class of myosin Va cargo. It has long been established that the yeast class V myosin, Myo4p, transports mRNAs along actin cables into the growing bud, and now several groups have reported a similar role for class V myosins in higher eukaryotes. Myosin Va has also been implicated in the assembly and maintenance of P-bodies (processing bodies), cytoplasmic foci that are involved in mRNA storage and degradation. The present review examines the evidence that myosin Va plays a role in the transport and turnover of mRNA.

scholarly journals Competitive binding of CUGBP1 and HuR to occludin mRNA controls its translation and modulates epithelial barrier function

2013 ◽  
Vol 24 (2) ◽  
pp. 85-99 ◽  
Author(s):  
Ting-Xi Yu ◽  
Jaladanki N. Rao ◽  
Tongtong Zou ◽  
Lan Liu ◽  
Lan Xiao ◽  
...  
Keyword(s):  
Barrier Function ◽  
Untranslated Region ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Cell Monolayer ◽  
Intestinal Epithelial ◽  
Processing Bodies ◽  
Epithelial Barrier Function ◽  
P Bodies ◽  
The Stability

RNA-binding proteins CUG-binding protein 1 (CUGBP1) and HuR are highly expressed in epithelial tissues and modulate the stability and translation of target mRNAs. Here we present evidence that CUGBP1 and HuR jointly regulate the translation of occludin and play a crucial role in the maintenance of tight junction (TJ) integrity in the intestinal epithelial cell monolayer. CUGBP1 and HuR competed for association with the same occludin 3′-untranslated region element and regulated occludin translation competitively and in opposite directions. CUGBP1 overexpression decreased HuR binding to occludin mRNA, repressed occludin translation, and compromised the TJ barrier function, whereas HuR overexpression inhibited CUGBP1 association with occludin mRNA and promoted occludin translation, thereby enhancing the barrier integrity. Repression of occludin translation by CUGBP1 was due to the colocalization of CUGBP1 and tagged occludin RNA in processing bodies (P-bodies), and this colocalization was prevented by HuR overexpression. These findings indicate that CUGBP1 represses occludin translation by increasing occludin mRNA recruitment to P-bodies, whereas HuR promotes occludin translation by blocking occludin mRNA translocation to P-bodies via the displacement of CUGBP1.

scholarly journals Proteomic analysis of Dhh1 complexes reveals a role for Hsp40 chaperone Ydj1 in yeast P-body assembly

2015 ◽  
Author(s):  
Gregory A. Cary ◽  
Dani B.N. Vinh ◽  
Patrick May ◽  
Rolf Kuestner ◽  
Aimee M. Dudley
Keyword(s):  
Rna Binding ◽  
Rna Binding Proteins ◽  
Active Role ◽  
Low Complexity ◽  
Mitochondrial Rna ◽  
P Bodies ◽  
Glucose Depletion ◽  
Catalytic Rnas ◽  
Rnp Granules

P-bodies (PB) are ribonucleoprotein (RNP) complexes that aggregate into cytoplasmic foci when cells are exposed to stress. While the conserved mRNA decay and translational repression machineries are known components of PB, how and why cells assemble RNP complexes into large foci remain unclear. Using mass spectrometry to analyze proteins immunoisolated with the core PB protein Dhh1, we show that a considerable number of proteins contain low-complexity (LC) sequences, similar to proteins highly represented in mammalian RNP granules. We also show that the Hsp40 chaperone Ydj1, which contains an LC domain and controls prion protein aggregation, is required for the formation of Dhh1-GFP foci upon glucose depletion. New classes of proteins that reproducibly co-enrich with Dhh1-GFP during PB induction include proteins involved in nucleotide or amino acid metabolism, glycolysis, tRNA aminoacylation, and protein folding. Many of these proteins have been shown to form foci in response to other stresses. Finally, analysis of RNA associated with Dhh1-GFP shows enrichment of mRNA encoding the PB protein Pat1 and catalytic RNAs along with their associated mitochondrial RNA-binding proteins, suggesting an active role for RNA in PB function. Thus, global characterization of PB composition has uncovered proteins and RNA that are important for PB assembly.

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.

scholarly journals Modifiers of solid RNP granules control normal RNP dynamics and mRNA activity in early development

2015 ◽  
Vol 211 (3) ◽  
pp. 703-716 ◽  
Author(s):  
Arnaud Hubstenberger ◽  
Cristiana Cameron ◽  
Scott L. Noble ◽  
Sean Keenan ◽  
Thomas C. Evans
Keyword(s):  
Caenorhabditis Elegans ◽  
Neurodegenerative Disorders ◽  
Large Scale ◽  
Rna Helicase ◽  
Rna Regulation ◽  
Mrna Regulation ◽  
Solid States ◽  
Rnp Granules ◽  
Polyq Expansion

Ribonucleoproteins (RNPs) often coassemble into supramolecular bodies with regulated dynamics. The factors controlling RNP bodies and connections to RNA regulation are unclear. During Caenorhabditis elegans oogenesis, cytoplasmic RNPs can transition among diffuse, liquid, and solid states linked to mRNA regulation. Loss of CGH-1/Ddx6 RNA helicase generates solid granules that are sensitive to mRNA regulators. Here, we identified 66 modifiers of RNP solids induced by cgh-1 mutation. A majority of genes promote or suppress normal RNP body assembly, dynamics, or metabolism. Surprisingly, polyadenylation factors promote RNP coassembly in vivo, suggesting new functions of poly(A) tail regulation in RNP dynamics. Many genes carry polyglutatmine (polyQ) motifs or modulate polyQ aggregation, indicating possible connections with neurodegenerative disorders induced by CAG/polyQ expansion. Several RNP body regulators repress translation of mRNA subsets, suggesting that mRNAs are repressed by multiple mechanisms. Collectively, these findings suggest new pathways of RNP modification that control large-scale coassembly and mRNA activity during development.

scholarly journals An Emerging Role for Post-translational Modifications in Regulating RNP Condensates in the Germ Line

2021 ◽  
Vol 8 ◽  
Author(s):  
Jennifer A. Schisa ◽  
Mohamed T. Elaswad
Keyword(s):  
Phase Separation ◽  
Binding Proteins ◽  
Rna Binding ◽  
Germ Line ◽  
Rna Binding Proteins ◽  
Model Systems ◽  
Subsequent Formation ◽  
Post Translational Modifications ◽  
Rnp Granules

RNA-binding proteins undergo regulated phase transitions in an array of cell types. The phase separation of RNA-binding proteins, and subsequent formation of RNP condensates or granules, occurs during physiological conditions and can also be induced by stress. Some RNP granules have roles in post-transcriptionally regulating mRNAs, and mutations that prevent the condensation of RNA-binding proteins can reduce an organism’s fitness. The reversible and multivalent interactions among RNP granule components can result in RNP complexes that transition among diffuse and condensed states, the latter of which can be pathological; for example, in neurons solid RNP aggregates contribute to disease states such as amyotrophic lateral sclerosis (ALS), and the dysregulation of RNP granules in human germ cells may be involved in Fragile X-associated primary ovarian insufficiency. Thus, regulating the assembly of mRNAs and RNA-binding proteins into discrete granules appears to provide important functions at both cellular and physiological levels. Here we review our current understanding of the role of post-translational modifications (PTMs) in regulating the condensation of RNA-binding proteins in the germ line. We compare and contrast the in vitro evidence that methylation inhibits phase separation of RNA binding proteins, with the extent to which these results apply to the in vivo germ line environment of several model systems. We also focus on the role of phosphorylation in modulating the dynamics of RNP granules in the germ line. Finally, we consider the gaps that exist in our understanding of the role of PTMs in regulating germ line RNP granules.

scholarly journals In vivo construction of recombinant molecules within the Caenorhabditis elegans germ line using short regions of terminal homology

2007 ◽  
Vol 35 (19) ◽  
pp. e133-e133 ◽  
Author(s):  
B. J. Kemp ◽  
J. Hatzold ◽  
L. A. Sternick ◽  
J. Cornman-Homonoff ◽  
J. M. Whitaker ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Germ Line
Sign in / Sign up

Export Citation Format

Share Document