PMID- 17512459
OWN - NLM
STAT- MEDLINE
DCOM- 20070724
LR  - 20191003
IS  - 0891-5849 (Print)
IS  - 0891-5849 (Linking)
VI  - 42
IP  - 12
DP  - 2007 Jun 15
TI  - Molecular mechanism of human Nrf2 activation and degradation: role of sequential 
      phosphorylation by protein kinase CK2.
PG  - 1797-806
AB  - Nrf2 is a key transcription factor in the cellular response to oxidative stress. 
      In this study we identify two phosphorylated forms of endogenous human Nrf2 after 
      chemically induced oxidative stress and provide evidence that protein kinase 
      CK2-mediated sequential phosphorylation plays potential roles in Nrf2 activation 
      and degradation. Human Nrf2 has a predicted molecular mass of 66 kDa. However, 
      immunoblots showed that two bands at 98 and 118 kDa, which are identified as 
      phosphorylated forms, are increased in response to Nrf2 inducers. In addition, 
      human Nrf2 was found to be a substrate for CK2 which mediated two steps of 
      phosphorylation, resulting in two forms of Nrf2 migrating with differing M(r) at 
      98 kDa (Nrf2-98) and 118 kDa (Nrf2-118). Our results support a role in which 
      calmodulin binding regulates CK2 activity, in that cold (25 degrees C) 
      Ca(2+)-free media (cold/Ca(2+)-free) decreased both cellular calcium levels and 
      CK2-calmodulin binding and induced Nrf2-118 formation, the latter of which was 
      prevented by CK2-specific inhibitors. Gel shift assays showed that the Nrf2-118 
      generated under cold/Ca(2+)-free conditions does not bind to the antioxidant 
      response element, indicating that Nrf2-98 has transcriptional activity. In 
      contrast, Nrf2-118 is more susceptible to degradation. These results provide 
      evidence for phosphorylation by CK2 as a critical controlling factor in 
      Nrf2-mediated cellular antioxidant response.
FAU - Pi, Jingbo
AU  - Pi J
AD  - Laboratory of Comparative Carcinogenesis, NCI at NIEHS, NIH, Research Triangle 
      Park, NC 27709, USA.
FAU - Bai, Yushi
AU  - Bai Y
FAU - Reece, Jeffrey M
AU  - Reece JM
FAU - Williams, Jason
AU  - Williams J
FAU - Liu, Dianxin
AU  - Liu D
FAU - Freeman, Michael L
AU  - Freeman ML
FAU - Fahl, William E
AU  - Fahl WE
FAU - Shugar, David
AU  - Shugar D
FAU - Liu, Jie
AU  - Liu J
FAU - Qu, Wei
AU  - Qu W
FAU - Collins, Sheila
AU  - Collins S
FAU - Waalkes, Michael P
AU  - Waalkes MP
LA  - eng
GR  - Z01 BC005488-21/Intramural NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Intramural
DEP - 20070312
PL  - United States
TA  - Free Radic Biol Med
JT  - Free radical biology & medicine
JID - 8709159
RN  - 0 (Calmodulin)
RN  - 0 (NF-E2-Related Factor 2)
RN  - 0 (NFE2L2 protein, human)
RN  - EC 2.7.11.1 (Casein Kinase II)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Blotting, Western
MH  - Calcium/metabolism
MH  - Calmodulin/metabolism
MH  - Casein Kinase II/*pharmacology
MH  - Cells, Cultured
MH  - Electrophoretic Mobility Shift Assay
MH  - *Gene Expression Regulation
MH  - Humans
MH  - Immunoprecipitation
MH  - Keratinocytes/cytology/metabolism
MH  - NF-E2-Related Factor 2/*metabolism
MH  - Phosphorylation
MH  - Plasmids
MH  - Protein Binding
MH  - Response Elements
MH  - Signal Transduction
MH  - Transcription, Genetic
MH  - Transcriptional Activation
PMC - PMC1950666
MID - NIHMS24322
EDAT- 2007/05/22 09:00
MHDA- 2007/07/25 09:00
PMCR- 2007/08/22
CRDT- 2007/05/22 09:00
PHST- 2006/05/13 00:00 [received]
PHST- 2007/01/25 00:00 [revised]
PHST- 2007/03/02 00:00 [accepted]
PHST- 2007/05/22 09:00 [pubmed]
PHST- 2007/07/25 09:00 [medline]
PHST- 2007/05/22 09:00 [entrez]
PHST- 2007/08/22 00:00 [pmc-release]
AID - S0891-5849(07)00176-1 [pii]
AID - 10.1016/j.freeradbiomed.2007.03.001 [doi]
PST - ppublish
SO  - Free Radic Biol Med. 2007 Jun 15;42(12):1797-806. doi: 
      10.1016/j.freeradbiomed.2007.03.001. Epub 2007 Mar 12.