Abstract
Transcriptional activation of the human CYPIA1 gene by halogenated and polycyclic aromatic hydrocarbons is mediated by the aryl hydrocarbon receptor (AhR) complex, a ligand-dependent transcription factor. A competent AhR comprises at least two components following nuclear translocation and DNA binding, the AhR and the AhR nuclear translocator (Arnt) protein, whose combined action on human CYP1A1 gene transcription is shown to be dependent upon functional protein kinase C (PKC). In the present study, we examined the effects of phorbol 12-myristate 13-acetate, a potent PKC activator, on the ligand-induced transcriptional activation of the CYPIA1 gene and cellular function of the AhR in human HepG2 101L cells. The 101L cells carry a stable transgene consisting of 1800 bases of 5'-flanking DNA and the promoter of the human CYPIA1 gene linked to the firefly luciferase structural gene (Postlind, H., Vu, T. P., Tukey, R. H. and Quattrochi, L. C. (1993) Toxicol. Appl. Pharmacol. 118, 255-262). Pretreatment of cells with 12-myristate 13-acetate enhanced ligand-induced CYPIA1 gene expression 2-3-fold. Inhibition of PKC activity blocked directly the transcriptional activation and the transactivation of the CYPIA1 gene, indicating a role for PKC in the AhR- mediated transcriptional activation process. However, the DNA binding activities of the in vitro activated and the induced nuclear AhR as measured by electrophoretic mobility shift analysis were not affected when CYPIA1 transcription was inhibited, indicating the actions of PKC to be a nuclear event that works in concert with or precedes AhR binding to the gene. These results illustrate that PKC is absolutely essential for the cellular and molecular events that control induction of CYPIA1 gene transcription.
| Original language | English |
|---|---|
| Pages (from-to) | 26261-26266 |
| Number of pages | 6 |
| Journal | Journal of Biological Chemistry |
| Volume | 271 |
| Issue number | 42 |
| DOIs | |
| Publication status | Published - 1996 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
Cite this
Protein kinase C modulates regulation of the CYP1A1 gene by the aryl hydrocarbon receptor. / Chen, Yue-Hwa; Tukey, Robert H.
In: Journal of Biological Chemistry, Vol. 271, No. 42, 1996, p. 26261-26266.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Protein kinase C modulates regulation of the CYP1A1 gene by the aryl hydrocarbon receptor
AU - Chen, Yue-Hwa
AU - Tukey, Robert H.
PY - 1996
Y1 - 1996
N2 - Transcriptional activation of the human CYPIA1 gene by halogenated and polycyclic aromatic hydrocarbons is mediated by the aryl hydrocarbon receptor (AhR) complex, a ligand-dependent transcription factor. A competent AhR comprises at least two components following nuclear translocation and DNA binding, the AhR and the AhR nuclear translocator (Arnt) protein, whose combined action on human CYP1A1 gene transcription is shown to be dependent upon functional protein kinase C (PKC). In the present study, we examined the effects of phorbol 12-myristate 13-acetate, a potent PKC activator, on the ligand-induced transcriptional activation of the CYPIA1 gene and cellular function of the AhR in human HepG2 101L cells. The 101L cells carry a stable transgene consisting of 1800 bases of 5'-flanking DNA and the promoter of the human CYPIA1 gene linked to the firefly luciferase structural gene (Postlind, H., Vu, T. P., Tukey, R. H. and Quattrochi, L. C. (1993) Toxicol. Appl. Pharmacol. 118, 255-262). Pretreatment of cells with 12-myristate 13-acetate enhanced ligand-induced CYPIA1 gene expression 2-3-fold. Inhibition of PKC activity blocked directly the transcriptional activation and the transactivation of the CYPIA1 gene, indicating a role for PKC in the AhR- mediated transcriptional activation process. However, the DNA binding activities of the in vitro activated and the induced nuclear AhR as measured by electrophoretic mobility shift analysis were not affected when CYPIA1 transcription was inhibited, indicating the actions of PKC to be a nuclear event that works in concert with or precedes AhR binding to the gene. These results illustrate that PKC is absolutely essential for the cellular and molecular events that control induction of CYPIA1 gene transcription.
AB - Transcriptional activation of the human CYPIA1 gene by halogenated and polycyclic aromatic hydrocarbons is mediated by the aryl hydrocarbon receptor (AhR) complex, a ligand-dependent transcription factor. A competent AhR comprises at least two components following nuclear translocation and DNA binding, the AhR and the AhR nuclear translocator (Arnt) protein, whose combined action on human CYP1A1 gene transcription is shown to be dependent upon functional protein kinase C (PKC). In the present study, we examined the effects of phorbol 12-myristate 13-acetate, a potent PKC activator, on the ligand-induced transcriptional activation of the CYPIA1 gene and cellular function of the AhR in human HepG2 101L cells. The 101L cells carry a stable transgene consisting of 1800 bases of 5'-flanking DNA and the promoter of the human CYPIA1 gene linked to the firefly luciferase structural gene (Postlind, H., Vu, T. P., Tukey, R. H. and Quattrochi, L. C. (1993) Toxicol. Appl. Pharmacol. 118, 255-262). Pretreatment of cells with 12-myristate 13-acetate enhanced ligand-induced CYPIA1 gene expression 2-3-fold. Inhibition of PKC activity blocked directly the transcriptional activation and the transactivation of the CYPIA1 gene, indicating a role for PKC in the AhR- mediated transcriptional activation process. However, the DNA binding activities of the in vitro activated and the induced nuclear AhR as measured by electrophoretic mobility shift analysis were not affected when CYPIA1 transcription was inhibited, indicating the actions of PKC to be a nuclear event that works in concert with or precedes AhR binding to the gene. These results illustrate that PKC is absolutely essential for the cellular and molecular events that control induction of CYPIA1 gene transcription.
UR - http://www.scopus.com/inward/record.url?scp=0029967886&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029967886&partnerID=8YFLogxK
U2 - 10.1074/jbc.271.42.26261
DO - 10.1074/jbc.271.42.26261
M3 - Article
C2 - 8824276
AN - SCOPUS:0029967886
VL - 271
SP - 26261
EP - 26266
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 42
ER -