Article

Genomic gems: SINE RNAs regulate mRNA production.

Department of Chemistry and Biochemistry, University of Colorado, Boulder, 80309-0215, USA.
Current opinion in genetics & development (impact factor: 8.99). 02/2010; 20(2):149-55. DOI:10.1016/j.gde.2010.01.004
Source: PubMed

ABSTRACT Mammalian short interspersed elements (SINEs) are abundant retrotransposons that have long been considered junk DNA; however, RNAs transcribed from mouse B2 and human Alu SINEs have recently been found to control mRNA production at multiple levels. Upon cell stress B2 and Alu RNAs bind RNA polymerase II (Pol II) and repress transcription of some protein-encoding genes. Bi-directional transcription of a B2 SINE establishes a boundary that places the growth hormone locus in a permissive chromatin state during mouse development. Alu RNAs embedded in Pol II transcripts can promote evolution and proteome diversity through exonization via alternative splicing. Given the diverse means by which SINE encoded RNAs impact production of mRNAs, this genomic junk is proving to contain hidden gems.

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Keywords

alternative splicing
 
Alu RNAs
 
Alu RNAs bind RNA polymerase II
 
B2 SINE
 
control mRNA production
 
gems
 
genomic junk
 
growth hormone locus
 
human Alu SINEs
 
junk DNA
 
Mammalian short interspersed elements
 
mRNAs
 
multiple levels
 
Pol II
 
Pol II transcripts
 
proteome diversity
 
RNAs transcribed
 
SINE encoded RNAs impact production
 
SINEs
 

Steven L Ponicsan