Isolation of an active gene and of two pseudogenes for mouse U7 small nuclear RNA - Gruber, A.; Soldati, D.; Burri, M.; Schumperli, D. (Elsevier)
Three U7 RNA-related sequences were isolated from mouse genomic DNA libraries. Only one of the sequences completely matches the published mouse U7 RNA sequence, whereas the other two apparently represent pseudogenes. The matching sequence represents a functional gene, as it is expressed after microinjection into Xenopus laevis oocytes. Sequence variations of the conserved cis-acting 5' and 3' elements of U RNA genes may partly explain the low abundance of U7 RNA.
http://dx.doi.org/10.1016/0167-4781(91)90167-K
Keywords: W; V; WW-YZ; U