@article{TEXTUAL,
      recid = {10677},
      author = {Tian, Sibo and Haney, Robert A. and Feder, Martin E.},
      title = {Phylogeny Disambiguates the Evolution of Heat-Shock  &amp;lt;i&amp;gt;cis&amp;lt;/i&amp;gt;-Regulatory Elements in  &amp;lt;i&amp;gt;Drosophila&amp;lt;/i&amp;gt;},
      journal = {PLOS ONE},
      address = {2010-05-17},
      number = {TEXTUAL},
      abstract = {&lt;p&gt;Heat-shock genes have a well-studied control mechanism  for their expression that is mediated through  &lt;em&gt;cis&lt;/em&gt;-regulatory motifs known as heat-shock elements  (HSEs). The evolution of important features of this control  mechanism has not been investigated in detail, however.  Here we exploit the genome sequencing of multiple  &lt;em&gt;Drosophila&lt;/em&gt; species, combined with a wealth of  available information on the structure and function of HSEs  in &lt;em&gt;D. melanogaster&lt;/em&gt;, to undertake this  investigation. We find that in single-copy heat shock  genes, entire HSEs have evolved or disappeared 14 times,  and the phylogenetic approach bounds the timing and  direction of these evolutionary events in relation to  speciation. In contrast, in the multi-copy gene  &lt;em&gt;Hsp70&lt;/em&gt;, the number of HSEs is nearly constant  across species. HSEs evolve in size, position, and sequence  within heat-shock promoters. In turn, functional  significance of certain features is implicated by  preservation despite this evolutionary change; these  features include tail-to-tail arrangements of HSEs, gapped  HSEs, and the presence or absence of entire HSEs. The  variation among &lt;em&gt;Drosophila&lt;/em&gt; species indicates that  the &lt;em&gt;cis&lt;/em&gt;-regulatory encoding of responsiveness to  heat and other stresses is diverse. The broad dimensions of  variation uncovered are particularly important as they  suggest a substantial challenge for functional  studies.&lt;/p&gt;},
      url = {http://knowledge.uchicago.edu/record/10677},
}