Analysis of the role of Nrf2 in the expression of liver proteins in mice using two-dimensional gel-based proteomics.
BACKGROUND
The transcription factor Nrf2 regulates expression of multiple cellular defence proteins through the antioxidant response element (ARE). Nrf2-deficient mice (Nrf2(-/-)) are highly susceptible to xenobiotic-mediated toxicity, but it is not known whether this reflects low basal expression or reduced inducibility of Nrf2-regulated genes in response to chemical insults.


METHODS
Wild type and Nrf2(-/-) mice were fed diet supplemented with the established Nrf2 inducer butylated hydroxyanisole (BHA) [0.5% (w/w)] for 14 days. To define the range of Nrf2-regulated proteins, both basally and following exposure to BHA, a comparison of the liver proteomes of Nrf2(-/-) and wild type mice was conducted. The two-dimensional gel electrophoresis (2-DE) technique and MALDI mass spectrometry were utilized in the attempt to define Nrf2-regulated proteins.


RESULTS
Overall, 24 proteins were identified, which were regulated either basally (3 proteins), inducibly (16 proteins), or both (5 proteins). These included several well-established Nrf2-driven gene products e.g., aldo-keto reductase and glutathione transferases. Multiple consensus ARE/ARE-like sequences were found in the Nrf2-regulated genes.


CONCLUSIONS
This study confirms the central role of Nrf2 in the induction of multiple defense proteins as well as its control in the constitutive expression of certain proteins.
Department of Pharmacology, University of Liverpool, Sherrington Buildings, Liverpool, Merseyside, L69 3GE, United Kingdom. manlah1969@yahoo.com
Azman
A
Abdullah
Neil R
NR
Kitteringham
Rosalind E
RE
Jenkins
Christopher
C
Goldring
Larry
L
Higgins
Masayuki
M
Yamamoto
John
J
Hayes
B Kevin
BK
Park
D000429:Alcohol Oxidoreductases / Q000378:metabolism; D000449:Aldehyde Reductase; D000074408:Aldo-Keto Reductases; D000818:Animals; D002083:Butylated Hydroxyanisole / Q000494:pharmacology*; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D005786:Gene Expression Regulation; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D050984:NF-E2 Transcription Factor, p45 Subunit / Q000235:genetics*; D011506:Proteins / Q000235:genetics*; D040901:Proteomics / Q000379:methods; D020218:Response Elements; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
D050984:NF-E2 Transcription Factor, p45 Subunit; C494693:Nfe2 protein, mouse; D011506:Proteins; D002083:Butylated Hydroxyanisole; D000429:Alcohol Oxidoreductases; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase; C000614209:AKR7A5 protein, mouse; D005982:Glutathione Transferase