TY - JOUR
T1 - Conserved regulatory elements in the promoters of two allelochemical- inducible cytochrome P450 genes differentially regulate transcription
AU - McDonnell, Cynthia M.
AU - Brown, Rebecca Petersen
AU - Berenbaum, May R.
AU - Schuler, Mary A.
N1 - Funding Information:
Ms. Erin Fancher made the −506/+29, −449/+29 and −286/+29 CYP6B4 promoter constructs, Dr. Hataichanoke Prapaipong Niamsup made the −146/+22 CYP6B1 wildtype promoter and Dr. Weimin Li provided the CYP6B4v2 genomic DNA clone for making the −1812/+29 CYP6B4 promoter construct. The internal actin: β-galactosidase control plasmid was a gift from Dr. Lucy Cherbas at Indiana University. This work has been supported by NSF grant IBN0212242 to MRB and USDA grant 01-35302-10884 to MAS and MRB. CMM was supported by fellowships from the University of Illinois Toxicology Scholars program and NIH Cell and Molecular Biology Training Grant at the University of Illinois Urbana-Champaign. RPB was supported by a fellowship from the University of Illinois Toxicology Scholars program.
PY - 2004/10
Y1 - 2004/10
N2 - CYP6B4, a cytochrome P450 gene from the tiger swallowtail Papilio glaucus, is transcriptionally induced in the midgut by dietary furanocoumarins, plant allelochemicals that can crosslink DNA in their UV-activated form. The CYP6B4 promoter contains an overlapping EcRE/ARE/XRE-xan element similar to that used for basal and xanthotoxin-inducible expression of the CYP6B1 promoter from the black swallowtail Papilio polyxenes. Transfection of the CYP6B4 promoter:CAT reporter construct into Sf9 cells demonstrates that the basal and xanthotoxin-inducible expression levels observed reflect the relative expression levels of this gene in the midguts of tiger swallowtail larvae. Transfections of mutant CYP6B4 promoter constructs into Sf9 cells indicate that the EcRE/ARE/XRE-xan element is necessary for CYP6B4 induction by xanthotoxin but not for its minimal basal expression. In addition to these elements, the CYP6B4 and CYP6B1 promoters also contain putative XRE-AhR elements identical to the aryl hydrocarbon response elements present in mammalian phase I detoxification genes. Transfections of CYP6B4 and CYP6B1 promoters containing EcRE/ARE/XRE-xan and XRE-AhR elements indicate that both are induced significantly by benzo(α)pyrene, an aryl hydrocarbon widespread in the environment, as well as by xanthotoxin, an allelochemical encountered in their hostplants.
AB - CYP6B4, a cytochrome P450 gene from the tiger swallowtail Papilio glaucus, is transcriptionally induced in the midgut by dietary furanocoumarins, plant allelochemicals that can crosslink DNA in their UV-activated form. The CYP6B4 promoter contains an overlapping EcRE/ARE/XRE-xan element similar to that used for basal and xanthotoxin-inducible expression of the CYP6B1 promoter from the black swallowtail Papilio polyxenes. Transfection of the CYP6B4 promoter:CAT reporter construct into Sf9 cells demonstrates that the basal and xanthotoxin-inducible expression levels observed reflect the relative expression levels of this gene in the midguts of tiger swallowtail larvae. Transfections of mutant CYP6B4 promoter constructs into Sf9 cells indicate that the EcRE/ARE/XRE-xan element is necessary for CYP6B4 induction by xanthotoxin but not for its minimal basal expression. In addition to these elements, the CYP6B4 and CYP6B1 promoters also contain putative XRE-AhR elements identical to the aryl hydrocarbon response elements present in mammalian phase I detoxification genes. Transfections of CYP6B4 and CYP6B1 promoters containing EcRE/ARE/XRE-xan and XRE-AhR elements indicate that both are induced significantly by benzo(α)pyrene, an aryl hydrocarbon widespread in the environment, as well as by xanthotoxin, an allelochemical encountered in their hostplants.
KW - Aryl hydrocarbon responses
KW - Cytochrome P450s
KW - Furanocoumarin responses
KW - Insect-plant interactions
KW - Transcriptional regulation
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U2 - 10.1016/j.ibmb.2004.06.014
DO - 10.1016/j.ibmb.2004.06.014
M3 - Article
C2 - 15475306
AN - SCOPUS:4744374959
SN - 0965-1748
VL - 34
SP - 1129
EP - 1139
JO - Insect Biochemistry and Molecular Biology
JF - Insect Biochemistry and Molecular Biology
IS - 10
ER -