New Insights Into the Evolution of Corticotropin-Releasing Hormone Family With a Special Focus on Teleosts.

Corticotropin-releasing hormone (CRH) was discovered for its role as a brain neurohormone controlling the corticotropic axis in vertebrates. An additional gene, , paralog of (), and likely resulting from the second round (2R) of vertebrate whole genome duplication (WGD), was identified in a holocephalan chondrichthyan, in basal mammals, various sauropsids and a non-teleost actinopterygian holostean. It was suggested that has been recurrently lost in some vertebrate groups including teleosts.