Pseudogenes for human small nuclear RNA U3 appear to arise by integration of self-primed reverse transcripts of the RNA into new chromosomal sites.

TitlePseudogenes for human small nuclear RNA U3 appear to arise by integration of self-primed reverse transcripts of the RNA into new chromosomal sites.
Publication TypeJournal Articles
Year of Publication1983
AuthorsBernstein LB, Mount SM, Weiner AM
JournalCell
Volume32
Issue2
Pagination461-72
Date Published1983 Feb
ISSN0092-8674
KeywordsAnimals, Base Sequence, DNA, genes, HUMANS, Nucleic Acid Conformation, Rats, Recombination, Genetic, Repetitive Sequences, Nucleic Acid, RNA, RNA, Small Nuclear, RNA-Directed DNA Polymerase, Templates, Genetic, Transcription, Genetic
Abstract

We find that both human and rat U3 snRNA can function as self-priming templates for AMV reverse transcriptase in vitro. The 74 base cDNA is primed by the 3' end of intact U3 snRNA, and spans the characteristically truncated 69 or 70 base U3 sequence found in four different human U3 pseudogenes. The ability of human and rat U3 snRNA to self-prime is consistent with a U3 secondary structure model derived by a comparison between rat U3 snRNA and the homologous D2 snRNA from Dictyostelium discoideum. We propose that U3 pseudogenes are generated in vivo by integration of a self-primed cDNA copy of U3 snRNA at new chromosomal sites. We also consider the possibility that the same cDNA mediates gene conversion at the 5' end of bona fide U3 genes where, over the entire region spanned by the U3 cDNA, the two rat U3 sequence variants U3A and U3B are identical.

Alternate JournalCell
PubMed ID6186397