CHASE4. This is an extracellular sensory domain, which is present in various classes of transmembrane receptors that are parts of signal transduction pathways in prokaryotes. Specifically, CHASE4 domains are found in histidine kinases in Archaea and in predicted diguanylate cyclases/phosphodiesterases in Bacteria. Environmental factors that are recognised by CHASE4 domains are not known at this time [1].

1: Common extracellular sensory domains in transmembrane receptors for diverse signal transduction pathways in bacteria and archaea. Zhulin IB, Nikolskaya AN, Galperin MY; J Bacteriol 2003;185:285-294. PMID:12486065