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Pearls are novel Cajal body-like structures in the Xenopus germinal vesicle that are dependent on RNA pol III transcription.

ABSTRACT: We have identified novel nuclear bodies, which we call pearls, in the giant oocyte nuclei of Xenopus laevis and Xenopus tropicalis. Pearls are attached to the lampbrush chromosomes at specific loci that are transcribed by RNA polymerase III, and they disappear after inhibition of polymerase III activity. Pearls are enriched for small Cajal body-specific RNAs (scaRNAs), which are guide RNAs that modify specific nucleotides on splicing snRNAs. Surprisingly, snRNAs themselves are not present in pearls, suggesting that pearls are not functionally equivalent to Cajal bodies in other systems, which contain both snRNAs and scaRNAs. We suggest that pearls may function in the processing of RNA polymerase III transcripts, such as tRNA, 5S rRNA, and other short non-coding RNAs.

SUBMITTER: Nizami ZF

PROVIDER: S-EPMC3566365 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Pearls are novel Cajal body-like structures in the Xenopus germinal vesicle that are dependent on RNA pol III transcription.

Nizami Zehra F ZF Gall Joseph G JG

Chromosome research : an international journal on the molecular, supramolecular and evolutionary aspects of chromosome biology 20121201 8

We have identified novel nuclear bodies, which we call pearls, in the giant oocyte nuclei of Xenopus laevis and Xenopus tropicalis. Pearls are attached to the lampbrush chromosomes at specific loci that are transcribed by RNA polymerase III, and they disappear after inhibition of polymerase III activity. Pearls are enriched for small Cajal body-specific RNAs (scaRNAs), which are guide RNAs that modify specific nucleotides on splicing snRNAs. Surprisingly, snRNAs themselves are not present in pea ...[more]

PMID: 23135638

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