The tertiary structures of porcine AhR and ARNT proteins and molecular interactions within the TCDD/AhR/ARNT complex.
The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that can be activated by structurally diverse synthetic and natural chemicals, including toxic environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In the present study, homology models of the porcine AhR-ligand binding domain (LBD) and the porcine aryl hydrocarbon receptor nuclear translocator-ligand binding domain (ARNT-LBD) were created on the basis of structures of closely related respective proteins i.e., human Hif-2α and ARNT. Molecular docking of TCDD to the porcine AhR-LBD model revealed high binding affinity (-8.8kcal/mol) between TCDD and the receptor. Moreover, formation of the TCDD/AhR-LBD complex was confirmed experimentally with the use of electrophoretic mobility shift assay (EMSA). It was found that TCDD (10nM, 2h of incubation) not only bound to the AhR in the porcine granulosa cells but also activated the receptor. The current study provides a framework for examining the key events involved in the ligand-dependent activation of the AhR.
Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland.
Karina
K
Orlowska
Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland.
Tomasz
T
Molcan
Laboratory of Molecular Diagnostics, University of Warmia and Mazury, Olsztyn, Poland.
Sylwia
S
Swigonska
Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland.
Agnieszka
A
Sadowska
Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland.
Monika
M
Jablonska
Laboratory of Molecular Diagnostics, University of Warmia and Mazury, Olsztyn, Poland.
Anna
A
Nynca
Department of Plant Physiology, Genetics and Biotechnology, University of Warmia and Mazury, Olsztyn, Poland.
Jan P
JP
Jastrzebski
Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland; Laboratory of Molecular Diagnostics, University of Warmia and Mazury, Olsztyn, Poland. Electronic address: reniac@uwm.edu.pl.
Renata E
RE
Ciereszko
D000595:Amino Acid Sequence; D000818:Animals; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D024202:Electrophoretic Mobility Shift Assay; D005260:Female; D006801:Humans; D008024:Ligands; D062105:Molecular Docking Simulation; D000072317:Polychlorinated Dibenzodioxins / Q000737:chemistry* / Q000378:metabolism*; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D018336:Receptors, Aryl Hydrocarbon / Q000737:chemistry* / Q000378:metabolism*; D016415:Sequence Alignment; D040681:Structural Homology, Protein; D034421:Sus scrofa
D008024:Ligands; D000072317:Polychlorinated Dibenzodioxins; D018336:Receptors, Aryl Hydrocarbon; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator
AhR; Docking study; Homology modeling; Pig; TCDD