RpoE

The gene rpoE encodes the sigma factor sigma-24, a protein in Escherichia coli and other species of bacteria. Depending on the bacterial species, this gene may be referred to as sigE.
RpoE appears to be necessary for the exocytoplasmic stress response. E. coli mutants without rpoE cannot grow at high temperatures and show growth defects at lower temperatures, though this may be due to compensatory mutations.
The stress response regulation activities of RpoE are modulated by the Hfq protein in E. coli.