Divergent Transcription: A Driving Force for New Gene Origination?

Computational and Systems Biology Graduate Program, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Cell (Impact Factor: 32.24). 11/2013; 155(5):990-996. DOI: 10.1016/j.cell.2013.10.048
Source: PubMed


The mammalian genome is extensively transcribed, a large fraction of which is divergent transcription from promoters and enhancers that is tightly coupled with active gene transcription. Here, we propose that divergent transcription may shape the evolution of the genome by new gene origination.

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    • "Several recent studies have advanced our understanding of new gene origins, their influence on genetic systems (including developmental networks), and the resulting effects on phenotypic evolution. Regarding origins, a study in mouse embryonic stem cells revealing pervasive bidirectional transcription suggested to the authors that opposite strand transcription could provide a robust source for new genes (Almada et al. 2013; Wu and Sharp 2013). Regarding genetic systems, studies of new genes in Drosophila (those present in just a few species) showed that they can quickly become essential for viability, male fertility, and foraging behavior (Chen et al. 2010; Chen, Ni, et al. 2012; Chen, Spletter, et al. 2012). "
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    • "RPL36aL is transcribed from a site some 1545 bp upstream, within <100 bp of the divergent initiation site of the MGAT2 gene. Since it is now clear that most promoters drive divergent transcription (Seila et al. 2009), we suggest that RPL36aL has been " fixed " in the " on " position, an example of a recent prediction (Wu and Sharp 2013). Excision of a 1422 nt intron from the 5 ′ UTR leaves the translation initiation site intact. "
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