IbpB thermometer (original) (raw)

The IbpB thermometer is an RNA thermometer element found in the ibpAB operon. The operon contains two heat-shock genes, encoding inclusion body binding proteins A and B (IbpA/B), and is the most drastically upregulated operon under heat-shock in Escherichia coli. IbpA is regulated by a ROSE element found in its 5' UTR, while IbpB has its own heat-sensitive cis-regulatory element. The activity of this thermoregulator was confirmed in vitro but was not found in vivo, suggesting more complicated operon regulation exists in bacterial cells.