Laminin induced local axonal translation of β-actin mRNA is impaired in SMN-deficient motoneurons

Localization of beta-actin mRNA to the leading edge of fibroblasts requires the presence of conserved elements in the 3' untranslated region of the mRNA, including a 54-nucleotide element which has been termed the "zipcode" (E. Kislauskis, X. Zhu, and R. H. Singer, J. Cell Biol. 127:441-451, 1994). In order to identify proteins which bind to the zipcode and possibly play a role in localization, we performed band-shift mobility assays, UV cross-linking, and affinity purification experiments. A protein of 68 kDa was identified which binds to the proximal (to the coding region) half of the zipcode with high specificity (ZBP-1). Microsequencing provided unique peptide sequences of approximately 15 residues each. Degenerate primers corresponding to the codons derived from the peptides were synthesized and used for PCR amplification. Screening of a chicken cDNA library resulted in isolation of several clones providing a DNA sequence encoding a 67.7-kDa protein with regions homologous to several RNA-binding proteins, such as hnRNP E1 and E2, and with consensus mRNA recognition motif with RNP1 and 2 motifs and a putative REV-like nuclear export signal. Antipeptide antibodies were raised in rabbits which bound to ZBP-1 and coimmunoprecipitated proteins of 120 and 25 kDa. The 120-kDa protein was also obtained by affinity purification with the RNA zipcode sequence, along with a 53-kDa protein, but the 25-kDa protein appeared only in immunoprecipitations. Mutation of one of the conserved sequences within the zipcode, an ACACCC element in its proximal half, greatly reduced its protein binding and localization properties. These data suggest that the 68-kDa ZBP-1 we have isolated and cloned is an RNA-binding protein that functions within a complex to localize beta-actin mRNA.

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Ability of adenovirus 5 E1A proteins to suppress differentiation of BC3H1 myoblasts correlates with their binding to a 300 kDa cellular protein.

Molecular Biology of the Cell ◽

10.1091/mbc.3.10.1107 ◽

1992 ◽

Vol 3 (10) ◽

pp. 1107-1115 ◽

Cited By ~ 40

Author(s):

J S Mymryk ◽

R W Lee ◽

S T Bayley

Keyword(s):

Creatine Kinase ◽

Kinase Activity ◽

Cellular Protein ◽

Creatine Kinase Activity ◽

Cellular Proteins ◽

Deletion Mutants ◽

Transcriptional Enhancers ◽

Actin Mrna ◽

Alpha Actin ◽

Adenovirus 5

We have used deletion mutants to define the regions in Ad5 E1A proteins necessary to suppress differentiation of mouse BC3H1 myoblasts. We examined the differentiation of cells infected at a low multiplicity with viruses containing the E1A deletions and constructed so as to produce only the smaller of the two major E1A proteins. Only four of the mutant viruses containing deletions within the N-terminal 69 residues failed to suppress differentiation as judged by changes in morphology and in levels of muscle-specific alpha-actin mRNA and creatine kinase activity. The results were confirmed by analyses of lines of cells stably transfected with representative E1A mutants. The mouse cellular proteins to which mutant E1A proteins bound were identified by immunoprecipitating E1A proteins specifically from infected BC3H1 cells and by analyzing the precipitates on denaturing gels. Bands of proteins of 300, 130, 107, 105 (the retinoblastoma product), and 60 kDa (cyclin A) were distinguished. Failure to suppress differentiation correlated with loss of binding to the 300-kDa protein but not to any of the others. The regions of E1A defined in this way have been shown to be required for several other activities, including enhancer repression and transformation. One function of the 300-kDa protein appears to be to facilitate the action of transcriptional enhancers of differentiation-specific genes.

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Asymmetrical β-actin mRNA translation in growth cones mediates attractive turning to netrin-1

Nature Neuroscience ◽

10.1038/nn1775 ◽

2006 ◽

Vol 9 (10) ◽

pp. 1247-1256 ◽

Cited By ~ 296

Author(s):

Kin-Mei Leung ◽

Francisca PG van Horck ◽

Andrew C Lin ◽

Rachel Allison ◽

Nancy Standart ◽

...

Keyword(s):

Mrna Translation ◽

Growth Cones ◽

Actin Mrna

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Novel chicken actin gene: third cytoplasmic isoform

Molecular and Cellular Biology ◽

10.1128/mcb.5.5.1151-1162.1985 ◽

1985 ◽

Vol 5 (5) ◽

pp. 1151-1162

Author(s):

D J Bergsma ◽

K S Chang ◽

R J Schwartz

Keyword(s):

Nucleotide Sequence ◽

Single Copy ◽

Actin Gene ◽

Single Copy Gene ◽

Gene Diversification ◽

Mrna Transcripts ◽

Copy Gene ◽

Actin Mrna ◽

Distinct Member ◽

Actin Protein

We identified a novel chicken actin gene. The actin protein deduced from its nucleotide sequence very closely resembles the vertebrate cytoplasmic actins; accordingly, we classified this gene as a nonmuscle type. We adopted the convention for indicating the nonmuscle actins of the class Amphibia (Vandekerckhove et al., J. Mol. Biol. 152:413-426) and denoted this gene as type 5. RNA blot analysis demonstrated that the type 5 actin mRNA transcripts accumulate in adult tissues in a pattern indicative of a nonmuscle actin gene. Genomic DNA blots indicated that the type 5 actin is a single copy gene and a distinct member of the chicken actin multigene family. Inspection of the nucleotide sequence revealed many features that distinguished the type 5 gene from all other vertebrate actin genes examined to date. These unique characteristics include: (i) an initiation Met codon preceding an Ala codon, a feature previously known only in plant actins, (ii) a single intron within the 5' untranslated region, with no interruptions in the coding portion of the gene, and (iii) an atypical Goldberg-Hogness box (ATAGAA) preceding the mRNA initiation terminus. These unusual features have interesting implications for actin gene diversification during evolution.

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Regulation of tubulin and actin mRNA production in rat brain: expression of a new beta-tubulin mRNA with development

Molecular and Cellular Biology ◽

10.1128/mcb.3.8.1333-1342.1983 ◽

1983 ◽

Vol 3 (8) ◽

pp. 1333-1342

Author(s):

J F Bond ◽

S R Farmer

Keyword(s):

Rat Brain ◽

Morphological Changes ◽

In Vitro Translation ◽

Brain Maturation ◽

Cdna Clones ◽

Mrna Levels ◽

Beta Tubulin ◽

Mrna Species ◽

Tubulin Mrna ◽

Actin Mrna

The expression of alpha-tubulin, beta-tubulin, and actin mRNA during rat brain development has been examined by using specific cDNA clones and in vitro translation techniques. During brain maturation (0 to 80 days postnatal), these mRNA species undergo a significant decrease in abundance. The kinetics of this decrease varies between the cerebrum and the cerebellum. These mRNAs are most abundant in both tissues during week 1 postnatal, each representing 10 to 15% of total mRNA activity. Both alpha- and beta-tubulin mRNA content decreases by 90 to 95% in the cerebrum after day 11 postnatal, and 70 to 80% decreases in the cerebellum after day 16. Actin sequences also decrease but to a lesser extent in both tissues (i.e., 50%). These decreases coincide with the major developmental morphological changes (i.e., neurite extension) occurring during this postnatal period. These studies have also identified the appearance of a new 2.5-kilobase beta-tubulin mRNA species, which is more predominant in the cerebellar cytoplasm. The appearance of this form occurs at a time when the major 1.8-kilobase beta-tubulin mRNA levels are declining. The possibility that the tubulin multigene family is phenotypically expressed and then this expression responds to the morphological state of the nerve cells is discussed.

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An amphibian cytoskeletal-type actin gene is expressed exclusively in muscle tissue

Development ◽

10.1242/dev.101.2.393 ◽

1987 ◽

Vol 101 (2) ◽

pp. 393-402 ◽

Cited By ~ 1

Author(s):

T.J. Mohun ◽

N. Garrett

Keyword(s):

Nucleotide Sequence ◽

Protein Isoforms ◽

Actin Gene ◽

Promoter Regions ◽

Conserved Sequence ◽

Beta Actin ◽

Genes Encoding ◽

Actin Mrna ◽

Ccaat Box ◽

Equivalent Region

The complete nucleotide sequence of two Xenopus actin genes encoding cytoskeletal protein isoforms has been determined. Transcripts from these genes are remarkably similar in nucleotide sequence throughout their length and code for type-5 and type-8 cytoskeletal actins. Both share some sequence homology with human gamma-actin mRNA within the 3′ untranslated region but none with the equivalent region of any vertebrate beta-actin transcript. The promoter regions of the two Xenopus genes are virtually identical from the cap site to the CCAAT box and show extensive homology further upstream. Despite such similarity, the two genes are divergently expressed during embryonic development. The type-5 actin gene is expressed in all regions of the developing embryo whilst the type-8 gene is coregulated with the muscle-specific skeletal actin gene. In common with mammalian and avian cytoskeletal actin counterparts, the Xenopus genes possess a conserved sequence within their promoter that has previously been identified as a transcription-factor-binding site.

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226.Regulated expression of adhesion and anti-adhesion molecules in mouse endometrium during early pregnancy

Reproduction Fertility and Development ◽

10.1071/srb04abs226 ◽

2004 ◽

Vol 16 (9) ◽

pp. 226 ◽

Cited By ~ 1

Author(s):

M. J. Jasper ◽

A. Stocker ◽

S. A. Robertson

Keyword(s):

Real Time ◽

Adhesion Molecules ◽

Early Pregnancy ◽

Embryo Implantation ◽

Early Embryo ◽

Luminal Epithelium ◽

Paracrine Factors ◽

Mean Values ◽

Actin Mrna ◽

Further Development

To implant and establish the connections that are vital for further development, the early embryo must attach to and then breech the barrier posed by the epithelium of the maternal tract. Expression of adhesion and anti-adhesion molecules in the luminal epithelium of the endometrium are thought to fluctuate in a temporal pattern to 'frame' the implantation site, with their expression regulated by endocrine and paracrine factors. Anti-adhesion molecules, such as members of the mucin family, provide a barrier to implantation in sites or at times unsuitable for embryo development. Expression of adhesion molecules, or specific integrins, are thought to aid in the adhesion of the embryo, allowing it to induce changes in the underlying tissue promoting embryo invasion and pregnancy. The aim of this study was to quantitate the expression of mRNA encoding the integrins αυ, α4 and β3 and MUC1 and MUC4 from Day 0 (oestrous) to Day 4 of pregnancy (implantation) using quantitative real time RT-PCR. Uterine tissues were collected at oestrous and at Days 1, 2, 3 and 4 of pregnancy (Day 1 corresponding to the presence of a vaginal plug), total RNA was extracted, DNAse treated, reverse transcribed into cDNA, and quantified by real-time PCR using SYBR Green chemistry. All specific primers were designed using GenBank sequences and data were normalised to β-actin mRNA expression. Expression of MUC1 and MUC4 mRNAs was dramatically reduced, with mean values 20-fold and 100-fold less than at oestrous respectively, by Day 4 of pregnancy. In contrast, expression of mRNAs encoding integrins αυ, α4 and β3 was detected throughout early pregnancy. These data demonstrate that adhesion and anti-adhesion molecules are differentially expressed in the murine uterus during early pregnancy and may be key mediators in embryo implantation, promoting attachment of the embryo to the luminal epithelium in an environment conducive to embryo growth and development. Supported by a Clive & Vera Ramaciotti Project Grant to MJ Jasper.

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