U3 (DF0001077)

This model represents a noncoding RNA gene. Some ncRNA genes have transformed into, or become assimilated into transposons. Others occur in sufficient copy number that ab initio repeat finders may classify them as repetitive elements. This entry is used to correctly identify the gene and its pseudogenes and prevent misannotation.

U3 snoRNA (small nucleolar RNA) gene / pseudogene


U3 is a uniquely-structured C/D box snoRNA; it is involved in pre-rRNA processing, rather than methylation. There are few genes, but >100 pseudogenes in human.


  1. Pseudogenes for human small nuclear RNA U3 appear to arise by integration of self-primed reverse transcripts of the RNA into new chromosomal sites.
    Bernstein LB, Mount SM, Weiner AM;
    Cell 1983;32:461-472 Pubmed


Accession Name Wikipedia
Type ncRNA Gene Article
Class snoRNA Article
Superfamily U3 Article

Hit Statistics

The model is 217 positions long. The average length of non-redundant hits to the model is 140.8. This table shows the number of hits above score thresholds:

Species Gathering Trusted
non-redundant all hits non-redundant all hits
Mus musculus 85 101 61 70
Homo sapiens 156 232 136 197
Danio rerio 42 44 41 42

External Database Links

  • Repbase : U3 [Requires Repbase registration]