|ZFIN ID: ZDB-PUB-081114-15|
The Antioxidant Defense System Keap1-Nrf2 Comprises a Multiple Sensing Mechanism for Responding to a Wide Range of Chemical Compounds
Kobayashi, M., Li, L., Iwamoto, N., Nakajima-Takagi, Y., Kaneko, H., Nakayama, Y., Eguchi, M., Wada, Y., Kumagai, Y., and Yamamoto, M.
|Source:||Molecular and cellular biology 29(2): 493-502 (Journal)|
|Registered Authors:||Kaneko, Hiroshi, Kobayashi, Makoto, Li, Li, Nakajima-Takagi, Yaeko, Yamamoto, Masayuki|
|PubMed:||19001094 Full text @ Mol. Cell. Biol.|
Kobayashi, M., Li, L., Iwamoto, N., Nakajima-Takagi, Y., Kaneko, H., Nakayama, Y., Eguchi, M., Wada, Y., Kumagai, Y., and Yamamoto, M. (2009) The Antioxidant Defense System Keap1-Nrf2 Comprises a Multiple Sensing Mechanism for Responding to a Wide Range of Chemical Compounds. Molecular and cellular biology. 29(2):493-502.
ABSTRACTAnimals have evolved defense systems for surviving in a chemically diverse environment. Such systems should bear plasticity, like adaptive immunity, enabling a response to even unknown chemicals. The antioxidant transcription factor Nrf2 is activated in response to various electrophiles and induces cytoprotective enzymes that detoxify them. We report here the discovery of a multiple sensing mechanism for Nrf2 activation using zebrafish and eleven Nrf2-activating compounds. Firstly, we showed that six of the compounds tested specifically target Cys-151 in Keap1, the ubiquitin ligase for Nrf2, while two compounds target Cys-273. Secondly, in addition to Nrf2 and Keap1, a third factor was deemed necessary for responding to three of the compounds. Finally, we isolated a zebrafish mutant defective in its response to seven compounds, but not to the remaining four. These results led us to categorize Nrf2 activators into six classes and hypothesize that multiple sensing allows enhanced plasticity in the system.