Molecular Mechanisms of Translational Control during the Early Development of Xenopus laevis

Richter, Joel D.

doi:10.1007/978-1-4684-5365-2_6

Cited by 15 publications

(18 citation statements)

References 136 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Certain maternal mRNAs possess short poly(A) tails that lengthen at the time of meiotic maturation and/or fertilization (Colot and Rosbash 1982;Rosenthal et al 1983;Dworkin and Dworkin-Rastl 1985;Fiuarte et al 1987;Rosenthal and Ruderman 1987). These increases in poly(A) tail length often are correlated with, and may cause, increases in translational efficiency (for review, see Richter 1987;Rosenthal and Wilt 1987). Clearly, sequences in the body of the mRNA must govern both the block in poly(A) extension and the relief of that block at fertilization.…”

Section: Discussionmentioning

confidence: 99%

Two phases in the addition of a poly(A) tail.

Sheets

Wickens²

1989

Genes Dev.

View full text Add to dashboard Cite

The addition of a poly(A) tail has been examined in a HeLa cell nuclear extract using SV40 late RNAs that end at or near the natural poly(A) site. We find that the addition of a full-length, 200-nucleotide poly(A) tail occurs in two discrete phases. In the first phase, the addition of each adenosine is dependent on the highly conserved sequence AAUAAA. Mutations in that sequence result in an accumulation of products that contain 9 or fewer adenosine residues. In the second phase, poly{A] addition no longer requires AAUAAA but, instead, requires the oligo(A) primer synthesized during the first phase. Thus, RNAs carrying an AAUAAA mutation and a 3'-terminal oligo{A) segment are extended efficiently to full-length poly(A). The transition between phases occurs with the addition of the tenth adenosine residue. An activity exists that limits the length of poly(A) added in the extract to -200 nucleotides. The two phases share at least one component and are likely to involve the same poly(A) polymerase.

show abstract

Section: Discussionmentioning

confidence: 99%

Two phases in the addition of a poly(A) tail.

Sheets

Wickens²

1989

Genes Dev.

View full text Add to dashboard Cite

show abstract

“…Studies on several Xenopus RNAs have shown that a sequence resembling UUUUUAU, termed the CPE, in addition to the hexanucleotide, is important for cytoplasmic polyadenylation during oocyte maturation (for review, see Richter et al 1990;Wickens 1990;Richter 1991;Bachvarova 1992). C12 RNA does not contain an exact copy of this sequence, but 31 nucleotides upstream [487][488][489][490][491][492][493][494][495][496][497][498][499][500][501][502][503][504], [486][487][488][489][490][491][492][493][494][495][496][497][498][499][500][501][502][503][504] (E), [485][486][487][488][489][490][491][492][493][494][495][496][497][498][499][500][501...…”

Section: Dodecauridine Functions As a Cpe For C12 Rnamentioning

confidence: 99%

“…Several of these maternal mRNAs, which are synthesized during oogenesis, are stored in a translationally inactive form but are assembled into polysomes during oocyte maturation, at fertilization, or during embryogenesis (Richter 1987;Jackson and Standart 1990). Although it is likely that no single mechanism dictates the timing of polysomal assembly of maternal mRNA during development, growing evidence suggests that at least during oocyte maturation, specific translation is con- trolled by poly(A) elongation and deadenylation.…”

mentioning

confidence: 99%

Translational control by poly(A) elongation during Xenopus development: differential repression and enhancement by a novel cytoplasmic polyadenylation element.

Simon¹,

Tassan²,

Richter³

1992

Genes & Development

153

127

View full text Add to dashboard Cite

One characteristic of oocyte maturation and embryogenesis in Xenopus laevis is the activation of translationally repressed (masked) maternal mRNAs by cytoplasmic poly(A) elongation. At maturation, poly(A) elongation is controlled by two cis-acting elements in the 3'-untranslated regions (UTRs) of responsive mRNAs, the hexanucleotide AAUAAA and the cytoplasmic polyadenylation element (CPE), consisting of UUUUUAU or other similar sequences. To investigate poly(A) elongation and translational activation during embryogenesis, we have focused on C12 RNA, a representative transcript that undergoes these processes. By injecting radiolabeled C12 RNA into fertilized eggs and allowing development to proceed, we found that maximal polyadenylation of this RNA is reached by the 4000-cell blastula stage and that it requires two cis-acting elements, the hexanucleotide AAUAAA and a novel CPE, which is dodecauridine. Interestingly, a shortening of the distance between the two elements changes the timing of maximal polyadenylation to the four-cell stage. The injection of a chloramphenicol acetyl transferase (CAT)-CI2 chimeric RNA into fertilized eggs not only results in embryonic polyadenylation of the transcript but also 5-to 15-fold more CAT activity compared with eggs injected with CAT RNA or CAT-CI2 chimeric RNA that is prevented from undergoing poly(A) elongation by a mutation in the polyadenylation hexanucleotide. However, eggs injected with a CAT-CI2 chimeric RNA that is preadenylated but that cannot undergo further poly(A) elongation contain no more CAT activity than eggs injected with the same RNA without a poly(A) tail, suggesting that the process of poly(A) elongation, and not poly(A) tail length, is important for translation. Finally, we show that precocious poly(A) elongation of C12 RNA during oocyte maturation is prevented by a large "masking" element that includes the dodecauridine CPE. The dual role of the CPE in both repression and activation of poly(A) elongation is discussed.

show abstract

“…In amphibians and in marine invertebrates, translational regulation is a common regulatory mechanism during oogenesis and early embryogenesis (Davidson 1986;Richter 1987;Rosenthal and Wilt 1987). In addition to there being a general overall inhibition of translation in unfertilized versus fertilized eggs, there are examples of both selective inhibition (Ford et al 1977)and selective activation (Rosenthal et al 1980) of translation.…”

Section: Translational Controlmentioning

confidence: 99%

Protamine 3'-untranslated sequences regulate temporal translational control and subcellular localization of growth hormone in spermatids of transgenic mice.

Braun¹,

Peschon²,

Behringer³

et al. 1989

Genes Dev.

228

173

View full text Add to dashboard Cite

Although the mouse protamine 1 gene (mP1) is first transcribed in round spermatids, its mRNA is not translated until about 1 week later in elongating spermatids. To determine what mP1 sequences are important for its transcriptional and translational regulation, we have constructed fusions between mP1 and the human growth hormone (hGH) structural gene and analyzed their expression in transgenic mice. We show that mP1 sequences 5' to the start of transcription are sufficient to confer spermatid-specific expression on the hGH gene. We also show that 156 nucleotides of mP1 3'-untranslated sequence is sufficient to confer mPl-like translational regulation on the hGH mRNA. Interestingly, the subcellular localization of hGH was dependent on the time during spermiogenesis that it was made. Synthesis of hGH in early round spermatids resulted in localization in the acrosome, whereas synthesis in late elongating spermatids resulted in intracellular, but not acrosomal, localization.

show abstract

Molecular Mechanisms of Translational Control during the Early Development of Xenopus laevis

Cited by 15 publications

References 136 publications

Two phases in the addition of a poly(A) tail.

Two phases in the addition of a poly(A) tail.

Translational control by poly(A) elongation during Xenopus development: differential repression and enhancement by a novel cytoplasmic polyadenylation element.

Protamine 3'-untranslated sequences regulate temporal translational control and subcellular localization of growth hormone in spermatids of transgenic mice.

Contact Info

Product

Resources

About