BC200 RNA: a neural RNA polymerase III product encoded by a monomeric Alu element.

AUTOR(ES)

Martignetti, J A

RESUMO

We demonstrate that the BC200 RNA gene, which encodes a neural small cytoplasmic RNA, is a member of the most prodigious family of interspersed repetitive DNA and that its product represents an example of a primate tissue-specific RNA polymerase III transcript. The BC200 RNA gene is an early monomeric member and one of the few postulated transcriptionally active Alu sequences in this family of nearly half a million retropositionally amplified elements dispersed throughout the human genome. Furthermore, the isolation of two pseudogenes, BC200 beta and BC200 gamma, demonstrates the gene's transpositional ability. Interestingly, the BC200 beta pseudogene may have been generated by a conversion-like event after the human/chimpanzee divergence, resulting in an exchange of the left arm of a dimeric Alu element with the BC200 RNA coding sequence. Our data on conserved features of the active BC200 alpha gene suggest that its RNA product has been "exapted" into a function of the primate brain and provides a selective advantage to the species.

Documentos Relacionados

• BC1 RNA: transcriptional analysis of a neural cell-specific RNA polymerase III transcript.
• The RNA polymerase III terminator used by a B1-Alu element can modulate 3' processing of the intermediate RNA product.
• Analysis of transcription of the human Alu family ubiquitous repeating element by eukaryotic RNA polymerase III.
• Neural BC1 RNA: cDNA clones reveal nonrepetitive sequence content
• Neural BC1 RNA: cDNA clones reveal nonrepetitive sequence content.