Identification of vegetal RNA-localization elements in Xenopus oocytes

Methods ◽  
2010 ◽  
Vol 51 (1) ◽  
pp. 146-151 ◽  
Author(s):  
Maike Claußen ◽  
Tomas Pieler
Keyword(s):  
Xenopus Oocytes ◽  
Rna Localization ◽  
Localization Elements

scholarly journals A Sponge-like Structure Involved in the Association and Transport of Maternal Products during Drosophila Oogenesis

1997 ◽  
Vol 139 (3) ◽  
pp. 817-829 ◽  
Author(s):  
Michaela Wilsch-Bräuninger ◽  
Heinz Schwarz ◽  
Christiane Nüsslein-Volhard
Keyword(s):  
Xenopus Oocytes ◽  
Polar Granule ◽  
Rna Localization ◽  
Drosophila Embryo ◽  
Fibrillar Structure ◽  
Subcellular Structure ◽  
Cytoplasmic Bridges ◽  
Dense Mass ◽  
Mitochondrial Cloud ◽  
Surrounding Membrane

Localization of maternally provided RNAs during oogenesis is required for formation of the antero–posterior axis of the Drosophila embryo. Here we describe a subcellular structure in nurse cells and oocytes which may function as an intracellular compartment for assembly and transport of maternal products involved in RNA localization. This structure, which we have termed “sponge body,” consists of ER-like cisternae, embedded in an amorphous electron-dense mass. It lacks a surrounding membrane and is frequently associated with mitochondria. The sponge bodies are not identical to the Golgi complexes. We suggest that the sponge bodies are homologous to the mitochondrial cloud in Xenopus oocytes, a granulo-fibrillar structure that contains RNAs involved in patterning of the embryo. Exuperantia protein, the earliest factor known to be required for the localization of bicoid mRNA to the anterior pole of the Drosophila oocyte, is highly enriched in the sponge bodies but not an essential structural component of these. RNA staining indicates that sponge bodies contain RNA. However, neither the intensity of this staining nor the accumulation of Exuperantia in the sponge bodies is dependent on the amount of bicoid mRNA present in the ovaries. Sponge bodies surround nuage, a possible polar granule precursor. Microtubules and microfilaments are not present in sponge bodies, although transport of the sponge bodies through the cells is implied by their presence in cytoplasmic bridges. We propose that the sponge bodies are structures that, by assembly and transport of included molecules or associated structures, are involved in localization of mRNAs in Drosophila oocytes.

fatvg encodes a new localized RNA that uses a 25-nucleotide element (FVLE1) to localize to the vegetal cortex of Xenopus oocytes

Development ◽  
1999 ◽  
Vol 126 (22) ◽  
pp. 4943-4953 ◽  
Author(s):  
A.P. Chan ◽  
M. Kloc ◽  
L.D. Etkin
Keyword(s):  
Cell Fate ◽  
Xenopus Oocytes ◽  
Single Copy ◽  
Biological Functions ◽  
Embryonic Patterning ◽  
Cis Acting ◽  
Maternal Transcript ◽  
Vegetal Cortex ◽  
Mitochondrial Cloud ◽  
Localization Elements

Vegetally localized transcripts have been implicated in a number of important biological functions, including cell fate determination and embryonic patterning. We have isolated a cDNA, fatvg, which encodes a localized maternal transcript that exhibits a localization pattern reminiscent of Vg1 mRNA. fatvg is the homologue of a mammalian gene expressed in adipose tissues. The fatvg transcript, unlike Vg1 which localizes strictly through the Late pathway, also associates with the mitochondrial cloud that is characteristic of the METRO or Early pathway. This suggests that fatvg mRNA may utilize both the METRO and Late pathways to localize to the vegetal cortex during oogenesis. We have dissected the cis-acting localization elements of fatvg mRNA and compared these elements with Vg1 mRNA. Our results indicate that, like most localized RNAs, in a variety of systems, transcripts of fatvg contain localization elements in the 3′UTR. The 3′UTR of fatvg mRNA contains multiple elements that are able to function independently; however, it functions most efficiently when all of the elements are present. We have defined a short 25-nucleotide element that can direct vegetal localization as a single copy. This element differs in sequence from previously described Vg1 localization elements, suggesting that different localization elements are involved in the localization of RNAs through the Late pathway.

scholarly journals Conserved and clustered RNA recognition sequences are a critical feature of signals directing RNA localization in Xenopus oocytes

2004 ◽  
Vol 121 (1) ◽  
pp. 101-109 ◽  
Author(s):  
Raymond A. Lewis ◽  
Tracy L. Kress ◽  
Colette A. Cote ◽  
Denise Gautreau ◽  
Megan E. Rokop ◽  
...  
Keyword(s):  
Xenopus Oocytes ◽  
Rna Localization ◽  
Rna Recognition ◽  
Critical Feature

scholarly journals PTB/hnRNP I Is Required for RNP Remodeling during RNA Localization in Xenopus Oocytes

2007 ◽  
Vol 28 (2) ◽  
pp. 678-686 ◽  
Author(s):  
Raymond A. Lewis ◽  
James A. Gagnon ◽  
Kimberly L. Mowry
Keyword(s):  
Protein Interactions ◽  
Xenopus Oocytes ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Rna Localization ◽  
Rna Transport ◽  
Rna Sequences ◽  
Cytoplasmic Rna ◽  
Embryonic Polarity ◽  
Specific Mrnas

ABSTRACT Transport of specific mRNAs to defined regions within the cell cytoplasm is a fundamental mechanism for regulating cell and developmental polarity. In the Xenopus oocyte, Vg1 RNA is transported to the vegetal cytoplasm, where localized expression of the encoded protein is critical for embryonic polarity. The Vg1 localization pathway is directed by interactions between key motifs within Vg1 RNA and protein factors recognizing those RNA sequences. We have investigated how RNA-protein interactions could be modulated to trigger distinct steps in the localization pathway and found that the Vg1 RNP is remodeled during cytoplasmic RNA transport. Our results implicate two RNA-binding proteins with key roles in Vg1 RNA localization, PTB/hnRNP I and Vg1RBP/vera, in this process. We show that PTB/hnRNP I is required for remodeling of the interaction between Vg1 RNA and Vg1RBP/vera. Critically, mutations that block this remodeling event also eliminate vegetal localization of the RNA, suggesting that RNP remodeling is required for localization.

scholarly journals She3p Possesses a Novel Activity Required for ASH1 mRNA Localization in Saccharomyces cerevisiae

2009 ◽  
Vol 8 (7) ◽  
pp. 1072-1083 ◽  
Author(s):  
Sharon M. Landers ◽  
Michelle R. Gallas ◽  
Jaime Little ◽  
Roy M. Long
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Rna Binding ◽  
Adaptor Protein ◽  
Mrna Localization ◽  
Rna Localization ◽  
The Novel ◽  
Specific Proteins ◽  
Type V ◽  
Localization Elements ◽  
Ash1 Mrna

ABSTRACT Intracellular and intercellular polarity requires that specific proteins be sorted to discreet locations within and between cells. One mechanism for sorting proteins is through RNA localization. In Saccharomyces cerevisiae, ASH1 mRNA localizes to the distal tip of the bud, resulting in the asymmetric sorting of the transcriptional repressor Ash1p. ASH1 mRNA localization requires four cis-acting localization elements and the trans-acting factors Myo4p, She3p, and She2p. Myo4p is a type V myosin motor that functions to directly transport ASH1 mRNA to the bud. She2p is an RNA-binding protein that directly interacts with the ASH1 mRNA cis-acting elements. Currently, the role for She3p in ASH1 mRNA localization is as an adaptor protein, since it can simultaneously associate with Myo4p and She2p. Here, we present data for two novel mutants of She3p, S348E and the double mutant S343E S361E, that are defective for ASH1 mRNA localization, and yet both of these mutants retain the ability to associate with Myo4p and She2p. These observations suggest that She3p possesses a novel activity required for ASH1 mRNA localization, and our data imply that this function is related to the ability of She3p to associate with ASH1 mRNA. Interestingly, we determined that She3p is phosphorylated, and global mass spectrometry approaches have determined that Ser 343, 348, and 361 are sites of phosphorylation, suggesting that the novel function for She3p could be negatively regulated by phosphorylation. The present study reveals that the current accepted model for ASH1 mRNA localization does not fully account for the function of She3p in ASH1 mRNA localization.

scholarly journals A bioinformatics search pipeline, RNA2DSearch, identifies RNA localization elements in Drosophila retrotransposons

RNA ◽  
2009 ◽  
Vol 15 (2) ◽  
pp. 200-207 ◽  
Author(s):  
R. S. Hamilton ◽  
E. Hartswood ◽  
G. Vendra ◽  
C. Jones ◽  
V. Van De Bor ◽  
...  
Keyword(s):  
Rna Localization ◽  
Localization Elements

scholarly journals Evidence for common machinery utilized by the early and late RNA localization pathways in Xenopus oocytes

2005 ◽  
Vol 278 (1) ◽  
pp. 103-117 ◽  
Author(s):  
Soheun Choo ◽  
Bianca Heinrich ◽  
J. Nicholas Betley ◽  
Zhao Chen ◽  
James O. Deshler
Keyword(s):  
Xenopus Oocytes ◽  
Rna Localization

Two copies of a subelement from the Vg1 RNA localization sequence are sufficient to direct vegetal localization in Xenopus oocytes

Development ◽  
1997 ◽  
Vol 124 (24) ◽  
pp. 5013-5020 ◽  
Author(s):  
D. Gautreau ◽  
C.A. Cote ◽  
K.L. Mowry
Keyword(s):  
Xenopus Oocytes ◽  
Rna Localization ◽  
Sequence Motifs ◽  
Sequence Element ◽  
Cis Acting ◽  
Vegetal Cortex ◽  
Sequence Elements ◽  
Localization Sequence ◽  
Localization Signal ◽  
Localization Element

Localization of mRNA has emerged as a fundamental mechanism for generating polarity during development. In vertebrates, one example of this phenomenon is Vg1 RNA, which is localized to the vegetal cortex of Xenopus oocytes. Vegetal localization of Vg1 RNA is directed by a 340-nt sequence element contained within its 3′ untranslated region. To investigate how such cis-acting elements function in the localization process, we have undertaken a detailed analysis of the precise sequence requirements for vegetal localization within the 340-nt localization element. We present evidence for considerable redundancy within the localization element and demonstrate that critical sequences lie at the ends of the element. Importantly, we show that a subelement from the 5′ end of the Vg1 localization element is, when duplicated, sufficient to direct vegetal localization. We suggest that the Vg1 localization element is composed of smaller, redundant sequence motifs and identify one such 6-nt motif as essential for localization. These results allow insight into what constitutes an RNA localization signal and how RNA sequence elements may act in the localization process.

Sign in / Sign up

Export Citation Format

Share Document