Spnr, a murine RNA-binding protein that is localized to cytoplasmic microtubules.

J M Schumacher; K Lee; S Edelhoff; R E Braun

doi:10.1083/jcb.129.4.1023

Spnr, a murine RNA-binding protein that is localized to cytoplasmic microtubules.

The Journal of Cell Biology ◽

10.1083/jcb.129.4.1023 ◽

1995 ◽

Vol 129 (4) ◽

pp. 1023-1032 ◽

Cited By ~ 67

Author(s):

J M Schumacher ◽

K Lee ◽

S Edelhoff ◽

R E Braun

Keyword(s):

Translational Control ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Translational Repression ◽

Rna Transport ◽

Binding Domains ◽

Cytoplasmic Microtubules ◽

Pachytene Spermatocytes ◽

Expression Libraries

Previous studies in transgenic mice have established the importance of the 3' untranslated region (UTR) of the spermatid-specific protamine-1 (Prm-1) mRNA in its translational control during male germ cell development. To clone genes that mediate the translational repression or activation of the Prm-1 mRNA, we screened cDNA expression libraries made with RNA from pachytene spermatocytes and round spermatids, with an RNA probe corresponding to the 3' UTR of Prm-1. We obtained six independent clones that encode Spnr, a spermatid perinuclear RNA-binding protein. Spnr is a 71-kD protein that contains two previously described RNA binding domains. The Spnr mRNA is expressed at high levels in the testis, ovary, and brain, and is present in multiple forms in those tissues. Immunolocalization of the Spnr protein within the testis shows that it is expressed exclusively in postmeiotic germ cells and that it is localized to the manchette, a spermatid-specific microtubular array. Although the Spnr protein is expressed too late to be directly involved in the translational repression of Prm-1 specifically, we suggest that the Spnr protein may be involved in other aspects of spermatid RNA metabolism, such as RNA transport or translational activation.

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The Nuclear RNA-binding Protein Sam68 Translocates to the Cytoplasm and Associates with the Polysomes in Mouse Spermatocytes

Molecular Biology of the Cell ◽

10.1091/mbc.e05-06-0548 ◽

2006 ◽

Vol 17 (1) ◽

pp. 14-24 ◽

Cited By ~ 60

Author(s):

Maria Paola Paronetto ◽

Francesca Zalfa ◽

Flavia Botti ◽

Raffaele Geremia ◽

Claudia Bagni ◽

...

Keyword(s):

Translational Control ◽

Rna Binding ◽

Rna Binding Proteins ◽

Binding Protein ◽

Rna Binding Protein ◽

Male Meiosis ◽

Binding Motif ◽

Mitogen Activated Protein ◽

Pachytene Spermatocytes ◽

And Function

Translational control plays a crucial role during gametogenesis in organisms as different as worms and mammals. Mouse knockout models have highlighted the essential function of many RNA-binding proteins during spermatogenesis. Herein we have investigated the expression and function during mammalian male meiosis of Sam68, an RNA-binding protein implicated in several aspects of RNA metabolism. Sam68 expression and localization within the cells is stage specific: it is expressed in the nucleus of spermatogonia, it disappears at the onset of meiosis (leptotene/zygotene stages), and it accumulates again in the nucleus of pachytene spermatocytes and round spermatids. During the meiotic divisions, Sam68 translocates to the cytoplasm where it is found associated with the polysomes. Translocation correlates with serine/threonine phosphorylation and it is blocked by inhibitors of the mitogen activated protein kinases ERK1/2 and of the maturation promoting factor cyclinB-cdc2 complex. Both kinases associate with Sam68 in pachytene spermatocytes and phosphorylate the regulatory regions upstream and downstream of the Sam68 RNA-binding motif. Molecular cloning of the mRNAs associated with Sam68 in mouse spermatocytes reveals a subset of genes that might be posttranscriptionally regulated by this RNA-binding protein during spermatogenesis. We also demonstrate that Sam68 shuttles between the nucleus and the cytoplasm in secondary spermatocytes, suggesting that it may promote translation of specific RNA targets during the meiotic divisions.

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Faculty Opinions recommendation of The cytoplasmic-localized, cytoskeletal-associated RNA binding protein OsTudor-SN: evidence for an essential role in storage protein RNA transport and localization.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1146956.604058 ◽

2009 ◽

Author(s):

Vitaly Citovsky ◽

Benoît Lacroix

Keyword(s):

Storage Protein ◽

Essential Role ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Rna Transport

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Regulation of Motility in Erwinia carotovora subsp. carotovora: Quorum-Sensing Signal Controls FlhDC, the Global Regulator of Flagellar and Exoprotein Genes, by Modulating the Production of RsmA, an RNA-Binding Protein

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-01-10-0017 ◽

2010 ◽

Vol 23 (10) ◽

pp. 1316-1323 ◽

Cited By ~ 21

Author(s):

Asita Chatterjee ◽

Yaya Cui ◽

Pranjib Chakrabarty ◽

Arun K. Chatterjee

Keyword(s):

Quorum Sensing ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Erwinia Carotovora ◽

Translational Repression ◽

Global Regulator ◽

Acylhomoserine Lactone ◽

Σ Factor ◽

Regulatory Effects

Erwinia carotovora subsp. carotovora causes soft-rotting (tissue-macerating) disease in many plants and plant organs. Although pectinases are the primary determinants of virulence, several ancillary factors that augment bacterial virulence have also been identified. One such factor is bacterial motility. Flagellum formation and bacterial movement are regulated in many enterobacteria, including E. carotovora subsp. carotovora, by FlhDC, the master regulator of flagellar genes and FliA, a flagellum-specific σ factor. We document here that motility of E. carotovora subsp. carotovora is positively regulated by the quorum-sensing signal, N-acylhomoserine lactone (AHL), and negatively regulated by RsmA, a post-transcriptional regulator. RsmA, an RNA-binding protein, causes translational repression and promotes RNA decay. Our data show that RsmA negatively regulates flhDC and fliA expression. Moreover, the chemical stabilities of transcripts of these genes are greater in an RsmA– mutant than in RsmA+ bacteria. These observations contrast with positive regulation of flhDC and motility by CsrA (= RsmA) in Escherichia coli. In the absence of AHL, the AHL receptors ExpR1/ExpR2 (= AhlR) in Erwinia carotovora subsp. carotovora negatively regulate motility and expression of flhDC and fliA by activating RsmA production. In the presence of AHL, regulatory effects of ExpR1/ExpR2 are neutralized, resulting in reduced levels of rsmA expression and enhanced motility.

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Modeling the binding specificity of the RNA-binding protein GLD-1 suggests a function of coding region-located sites in translational repression

RNA ◽

10.1261/rna.037531.112 ◽

2013 ◽

Vol 19 (10) ◽

pp. 1317-1326 ◽

Cited By ~ 16

Author(s):

A. Brummer ◽

S. Kishore ◽

D. Subasic ◽

M. Hengartner ◽

M. Zavolan

Keyword(s):

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Binding Specificity ◽

Translational Repression ◽

Coding Region

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Dynamic regulation of immunity through post-translational control of defense transcript splicing

10.1101/736249 ◽

2019 ◽

Author(s):

Keini Dressano ◽

Philipp R Weckwerth ◽

Elly Poretsky ◽

Yohei Takahashi ◽

Carleen Villarreal ◽

...

Keyword(s):

Immune Responses ◽

Translational Control ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Negative Regulator ◽

Signaling Proteins ◽

Receptor Signaling ◽

Post Translational Modification ◽

Defense Signaling

AbstractSurvival of all living organisms requires the ability to detect attack and swiftly counter with protective immune responses. Despite considerable mechanistic advances, interconnectivity of signaling circuits often remains unclear. A newly-characterized protein, IMMUNOREGULATORY RNA-BINDING PROTEIN (IRR), negatively regulates immune responses in both maize and Arabidopsis, with disrupted function resulting in enhanced disease resistance. IRR physically interacts with, and promotes canonical splicing of, transcripts encoding defense signaling proteins, including the key negative regulator of pattern recognition receptor signaling complexes, CALCIUM-DEPENDENT PROTEIN KINASE 28 (CPK28). Upon immune activation by Plant Elicitor Peptides (Peps), IRR is dephosphorylated, disrupting interaction withCPK28transcripts and resulting in accumulation of an alternative splice variant encoding a truncated CPK28 protein with impaired kinase activity and diminished function as a negative regulator. We demonstrate a novel circuit linking Pep-induced post-translational modification of IRR with post-transcriptionally-mediated attenuation of CPK28 function to dynamically amplify Pep signaling and immune output.One Sentence SummaryPlant innate immunity is promoted by post-translational modification of a novel RNA-binding protein that regulates alternative splicing of transcripts encoding defense signaling proteins to dynamically increase immune receptor signaling capacity through deactivation of a key signal-buffering circuit.

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Multivalent interactions with RNA drive RNA binding protein recruitment and dynamics in biomolecular condensates in Xenopus oocytes

10.1101/2021.06.21.449303 ◽

2021 ◽

Author(s):

Sarah E Cabral ◽

Kimberly Mowry

Keyword(s):

Protein Interactions ◽

Rna Binding ◽

Rna Binding Proteins ◽

Binding Protein ◽

Rna Binding Protein ◽

Dependent Manner ◽

Binding Domains ◽

Multivalent Interactions

RNA localization and biomolecular condensate formation are key biological strategies for organizing the cytoplasm and generating cellular and developmental polarity. While enrichment of RNAs and RNA-binding proteins (RBPs) is a hallmark of both processes, the functional and structural roles of RNA-RNA and RNA-protein interactions within condensates remain unclear. Recent work from our laboratory has shown that RNAs required for germ layer patterning in Xenopus oocytes localize in novel biomolecular condensates, termed Localization bodies (L-bodies). L-bodies are composed of a non-dynamic RNA phase enmeshed in a more dynamic protein-containing phase. However, the interactions that drive the biophysical characteristics of L-bodies are not known. Here, we test the role of RNA-protein interactions using an L-body RNA-binding protein, PTBP3, which contains four RNA-binding domains (RBDs). We find that binding of RNA to PTB is required for both RNA and PTBP3 to be enriched in L-bodies in vivo. Importantly, while RNA binding to a single RBD is sufficient to drive PTBP3 localization to L-bodies, interactions between multiple RRMs and RNA tunes the dynamics of PTBP3 within L-bodies. In vitro, recombinant PTBP3 phase separates into non-dynamic structures in an RNA-dependent manner, supporting a role for RNA-protein interactions as a driver of both recruitment of components to L-bodies and the dynamics of the components after enrichment. Our results point to a model where RNA serves as a concentration-dependent, non-dynamic substructure and multivalent interactions with RNA are a key driver of protein dynamics.

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Multiple Mechanisms Inactivate the LIN-41 RNA-Binding Protein to Ensure A Robust Oocyte-to-Embryo Transition in Caenorhabditis elegans

10.1101/378398 ◽

2018 ◽

Author(s):

Caroline A. Spike ◽

Gabriela Huelgas-Morales ◽

Tatsuya Tsukamoto ◽

David Greenstein

Keyword(s):

Caenorhabditis Elegans ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Adaptor Protein ◽

Protein Translation ◽

Translational Repression ◽

Meiotic Maturation ◽

Oocyte Growth ◽

Translational Repressor

ABSTRACTIn the nematode Caenorhabditis elegans, the conserved LIN-41 RNA-binding protein is a translational repressor that coordinately controls oocyte growth and meiotic maturation. LIN-41 exerts these effects, at least in part, by preventing the premature activation of the cyclin-dependent kinase CDK-1. Here we investigate the mechanism by which LIN-41 is rapidly eliminated upon the onset of meiotic maturation. Elimination of LIN-41 requires the activities of CDK-1 and multiple SCF-type ubiquitin ligase subunits, including the conserved substrate adaptor protein SEL-10/Fbw7/Cdc4, suggesting that LIN-41 is a target of ubiquitin-mediated protein degradation. Within the LIN-41 protein, two non-overlapping regions, Deg-A and Deg-B, are individually necessary for LIN-41 degradation; both contain several potential phosphodegron sequences, and at least one of these sites is required for LIN-41 degradation. Finally, Deg-A and Deg-B are sufficient, in combination, to mediate SEL-10-dependent degradation when transplanted into a different oocyte protein. Although LIN-41 is a potent inhibitor of protein translation and M-phase entry, the failure to eliminate LIN-41 from early embryos does not result in the continued translational repression of LIN-41 oocyte mRNA targets. Based on these observations, we propose a molecular model for the elimination of LIN-41 by SCFSEL-10 and suggest that LIN-41 is inactivated before it is degraded. Furthermore, we provide evidence that another RNA-binding protein, the GLD-1 tumor suppressor, is regulated similarly. Redundant mechanisms to extinguish translational repression by RNA-binding proteins may both control and provide robustness to irreversible developmental transitions, including meiotic maturation and the oocyte-to-embryo transition.

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Combinatorial recognition of clustered RNA elements by a multidomain RNA-binding protein, IMP3

10.1101/398008 ◽

2018 ◽

Cited By ~ 1

Author(s):

Tim Schneider ◽

Lee-Hsueh Hung ◽

Masood Aziz ◽

Anna Wilmen ◽

Stephanie Thaum ◽

...

Keyword(s):

Binding Proteins ◽

Rna Binding ◽

Rna Binding Proteins ◽

Binding Protein ◽

Rna Binding Protein ◽

Binding Domains ◽

Systematic Strategy ◽

Rna Elements ◽

Target Rna

AbstractHow multidomain RNA-binding proteins recognize their specific target sequences, based on a combinatorial code, represents a fundamental unsolved question and has not been studied systematically so far. Here we focus on a prototypical multidomain RNA-binding protein, IMP3 (also called IGF2BP3), which contains six RNA-binding domains (RBDs): four KH and two RRM domains. We have established an integrative systematic strategy, combining single-domain-resolved SELEX-seq, motif-spacing analyses, in vivo iCLIP, functional validation assays, and structural biology. This approach identifies the RNA-binding specificity and RNP topology of IMP3, involving all six RBDs and a cluster of up to five distinct and appropriately spaced CA-rich and GGC-core RNA elements, covering a >100 nucleotide-long target RNA region. Our generally applicable approach explains both specificity and flexibility of IMP3-RNA recognition, providing a paradigm for the function of multivalent interactions with multidomain RNA-binding proteins in gene regulation.

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FOG-2, a novel F-box containing protein, associates with the GLD-1 RNA binding protein and directs male sex determination in the C. elegans hermaphrodite germline

Development ◽

10.1242/dev.127.24.5265 ◽

2000 ◽

Vol 127 (24) ◽

pp. 5265-5276 ◽

Cited By ~ 9

Author(s):

R. Clifford ◽

M.H. Lee ◽

S. Nayak ◽

M. Ohmachi ◽

F. Giorgini ◽

...

Keyword(s):

Sex Determination ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Translational Repression ◽

Specific Substrate ◽

Interaction Domain ◽

C Elegans ◽

Male Sex ◽

F Box Protein

Male sex determination in the Caenorhabditis elegans hermaphrodite germline requires translational repression of tra-2 mRNA by the GLD-1 RNA binding protein. We cloned fog-2 by finding that its gene product physically interacts with GLD-1, forming a FOG-2/GLD-1/tra-2 3′untranslated region ternary complex. FOG-2 has an N-terminal F-box and a novel C-terminal domain called FTH. Canonical F-box proteins act as bridging components of the SCF ubiquitin ligase complex; the N-terminal F-box binds a Skp1 homolog, recruiting ubiquination machinery, while a C-terminal protein-protein interaction domain binds a specific substrate for degradation. However, since both fog-2 and gld-1 are necessary for spermatogenesis, FOG-2 cannot target GLD-1 for ubiquitin-mediated degradation. We propose that FOG-2 also acts as a bridge, bringing GLD-1 bound to tra-2 mRNA into a multiprotein translational repression complex, thus representing a novel function for an F-box protein. fog-2 is a member of a large, apparently rapidly evolving, C. elegans gene family that has expanded, in part, by local duplications; fog-2 related genes have not been found outside nematodes. fog-2 may have arisen during evolution of self-fertile hermaphroditism from an ancestral female/male species.

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