Hsp90 cis-regulatory element

The Hsp90 cis regulatory element is an RNA element (RNA thermometer) found in the 5' UTR of the "Drosophila" hsp90 mRNA. It is required for increased translational efficiency during the heat shock response.
The hsp90 gene product is involved in the "Drosophila" heat shock response. Translation of the hsp90 mRNA is very inefficient under normal growth temperatures, when heat shock occurs translation becomes more efficient. This is mediated though this regulatory element.