Functional consequences of bidirectional promoters

Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
Trends in Genetics (Impact Factor: 11.6). 07/2011; 27(7):267-76. DOI: 10.1016/j.tig.2011.04.002
Source: PubMed

ABSTRACT Several studies have shown that promoters of protein-coding genes are origins of pervasive non-coding RNA transcription and can initiate transcription in both directions. However, only recently have researchers begun to elucidate the functional implications of this bidirectionality and non-coding RNA production. Increasing evidence indicates that non-coding transcription at promoters influences the expression of protein-coding genes, revealing a new layer of transcriptional regulation. This regulation acts at multiple levels, from modifying local chromatin to enabling regional signal spreading and more distal regulation. Moreover, the bidirectional activity of a promoter is regulated at multiple points during transcription, giving rise to diverse types of transcripts.

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Available from: Vicent Pelechano, Apr 17, 2014
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    • "Remarkably, fusing the mRNA capping enzymes to a mutant CTD containing all Ser5 residues replaced by Ala was sufficient to restore viability in fission yeast, revealing that, at least in yeast, the main essential function of CTD Ser5 phosphorylation is recruitment of the capping machinery [28]. A surprising discovery from genome-wide analysis was the finding that many genes that are not being expressed contain Pol II initiation complexes engaged with the promoter and may generate short abortive non-coding RNAs that are reminiscent of cryptic unstable transcripts or CUTs [29] [30]. This is the case for genes regulated at specific development stages or inducible genes that need to rapidly respond to specific stimuli. "
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    • "Since the AK038749 and Syn2 transcription initiation sites are positioned only ~200 bp from each other, it is possible that proviruses activate a bidirectional mouse promoter. In fact, promoters of many coding genes transcribe non-coding RNAs in the opposite direction [59]. "
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    • "The existence of long noncoding RNAs (lncRNAs) is widespread in eukaryotes from yeast to mammals (Guttman and Rinn, 2012; Jacquier, 2009). Long noncoding transcripts in yeast influence gene expression, revealing a new layer of transcriptional regulation (Wei et al., 2011; Wu et al., 2012). LncRNAs might regulate transcription at multiple levels. "
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