Article

Primate MicroRNAs miR-220 and miR-492 Lie within Processed Pseudogenes

Molecular Genetics and Bioinformatics, Integrated DNA Technologies, 1710 Commercial Park, Coralville, IA 52241, USA.
Journal of Heredity (Impact Factor: 1.97). 03/2006; 97(2):186-90. DOI: 10.1093/jhered/esj022
Source: PubMed

ABSTRACT 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.

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Available from: Eric J Devor, Jul 29, 2015
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    • "However, many of them are known to produce new, very often lineage-specific genes (Betran, Wang, et al. 2002; Marques et al. 2005; Svensson et al. 2006). They can also lead to new protein domains through fusion with other genes (Vinckenbosch et al. 2006; Baertsch et al. 2008), regulatory RNAs (Yano et al. 2004; Devor 2006), or other regulatory elements (Nozawa et al. 2005). Soares et al. (1985) discovered for the first time a functional retrosequence in the rodent genome in 1985. "
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    • "However, many of them are known to produce new, very often lineage-specific genes (Betran, Wang, et al. 2002; Marques et al. 2005; Svensson et al. 2006). They can also lead to new protein domains through fusion with other genes (Vinckenbosch et al. 2006; Baertsch et al. 2008), regulatory RNAs (Yano et al. 2004; Devor 2006), or other regulatory elements (Nozawa et al. 2005). Soares et al. (1985) discovered for the first time a functional retrosequence in the rodent genome in 1985. "
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    • "In the cytoplasm, Dicer complexes (RNase III) cut the loops of pre-miRNAs resulting in a double stranded structure. Usually one strand is then incorporated into the RISC (RNA Induced Silencing Complex) while the other strand is degraded (Devor, 2006; Lee et al., 2002; Saini et al., 2007). Mutations in miRNAs have been shown to disrupt their maturation process at different stages or hamper their regulatory roles in translation processes (Sun et al., 2009), giving rise to disease phenotypes including neurodegeneration (Lee et al., 2008), and cancer (Melo and Esteller, 2011)). "
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