Primate microRNAs miR-220 and miR-492 lie within processed pseudogenes.
MicroRNAs (miRNAs) are a new and abundant class of small, noncoding RNAs. To date, the evolutionary history of most of these loci appears to be marked by duplication and divergence. The ultimate origin of miRNAs remains an open question. A survey of the genomic context of more than 300 human miRNA loci revealed that two primate-specific miRNAs, miR-220 and miR-492, each lie within a processed pseudogene. In silico and in vitro examinations of these two loci suggest that this is a rare phenomenon requiring the juxtaposition of a specific combination of factors. Thus it appears that, while processed pseudogenes are good candidates for miRNA incubators, it is unlikely that more than a very small percentage of new miRNAs arise this way.
Molecular Genetics and Bioinformatics, Integrated DNA Technologies, 1710 Commercial Park, Coralville, IA 52241, USA. rdevor@idtdna.com
Eric J
EJ
Devor
D000818:Animals; D001483:Base Sequence; D006801:Humans; D008253:Macaca mulatta / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics*; D009690:Nucleic Acid Conformation; D002679:Pan troglodytes / Q000235:genetics; D011148:Pongo pygmaeus / Q000235:genetics; D011323:Primates / Q000235:genetics*; D011544:Pseudogenes / Q000235:genetics*; D016415:Sequence Alignment
D035683:MicroRNAs