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bioRxiv · 10.1101/044362

Cis-regulatory evolution in prokaryotes revealed by interspecific archaeal hybrids.

Carlo Artieri·Adit Naor·Israela Turgeman-Grott·Yiqi Zhou·Ryan York·Uri Gophna·Hunter Fraser
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Abstract

The study of allele-specific expression (ASE) in interspecific hybrids has played a central role in our understanding of a wide range of phenomena, including genomic imprinting, X-chromosome inactivation, and cis-regulatory evolution. However across the hundreds of studies of hybrid ASE, all have been restricted to sexually reproducing eukaryotes, leaving a major gap in our understanding of the genomic patterns of cis-regulatory evolution in prokaryotes. Here we introduce a method to generate stable hybrids between two species of halophilic archaea, and measure genome-wide ASE in these hybrids with RNA-seq. We found that over half of all genes have significant ASE, and that genes encoding kinases show evidence of lineage-specific selection on their cis-regulation. This pattern of polygenic selection suggested species-specific adaptation to low phosphate conditions, which we confirmed with growth experiments. Altogether, our work extends the study of ASE to archaea, and suggests that cis-regulation can evolve under polygenic lineage-specific selection in prokaryotes.

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Carlo Artieri, Adit Naor, Israela Turgeman-Grott, Yiqi Zhou, Ryan York, Uri Gophna, Hunter Fraser. 2016-03-17. Cis-regulatory evolution in prokaryotes revealed by interspecific archaeal hybrids.. https://doi.org/10.1101/044362

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