Keap It in the Family: How to Fish out New Paradigms in Keap1-Mediated Cell Signaling

Keap1 is associated with cytoprotective signaling. These roles of Keap1 typically focus on its role as a degrader of the antioxidant response (AR) transcription factor, Nrf2, and the inhibition of this process upon Keap1 labeling by electrophiles. However, work from several laboratories has reemphasized both the important role of Nrf2 binding in negatively regulating AR, and the fact that electrophile Keap1 modification dissociates Nrf2 from Keap1. This model appears to be applicable to other signaling modes regulated by Keap1. Here, we use recent data we have derived using experiments in zebrafish and cultured cells to discuss different models of Keap1 regulation.