Previous Article | Next Article 
Molecular and Cellular Biology, March 2001, p. 1700-1709, Vol. 21, No. 5
0270-7306/01/$04.00+0 DOI: 10.1128/MCB.21.5.1700-1709.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Proteasome Inhibition Induces Nuclear Translocation
and Transcriptional Activation of the Dioxin Receptor in Mouse Embryo
Primary Fibroblasts in the Absence of Xenobiotics
Belen
Santiago-Josefat,
Eulalia
Pozo-Guisado,
Sonia
Mulero-Navarro, and
Pedro M.
Fernandez-Salguero*
Departamento de Bioquímica y
Biología Molecular y Genética, Facultad de Ciencias,
Universidad de Extremadura, 06071 Badajoz, Spain
Received 1 June 2000/Returned for modification 13 July
2000/Accepted 11 November 2000
The aryl hydrocarbon receptor (AHR) is a transcription factor that
is highly conserved during evolution and shares important structural
features with the Drosophila developmental regulators Sim and Per. Although much is known about the
mechanism of AHR activation by xenobiotics, little information is
available regarding its activation by endogenous stimuli in the absence
of exogenous ligand. In this study, using embryonic primary
fibroblasts, we have analyzed the role of proteasome inhibition on AHR
transcriptional activation in the absence of xenobiotics. Proteasome
inhibition markedly reduced cytosolic AHR without affecting its total
cellular content. Cytosolic AHR depletion was the result of receptor
translocation into the nuclear compartment, as shown by transient
transfection of a green fluorescent protein-tagged AHR and by
immunoblot analysis of nuclear extracts. Gel retardation experiments
showed that proteasome inhibition induced transcriptionally active
AHR-ARNT heterodimers able to bind to a consensus xenobiotic-responsive
element. Furthermore, nuclear AHR was transcriptionally active in vivo,
as shown by the induction of the endogenous target gene CYP1A2.
Synchronized to AHR activation, proteasome inhibition also induced a
transient increase in AHR nuclear translocator (ARNT) at the protein
and mRNA levels. Since nuclear levels of AHR and ARNT are relevant for
AHR transcriptional activation, our data suggest that proteasome inhibition, through a transient increase in ARNT expression, could promote AHR stabilization and accumulation into the nuclear
compartment. An elevated content of nuclear AHR could favor AHR-ARNT
heterodimers able to bind to xenobiotic-responsive elements and to
induce gene transcription in the absence of xenobiotics. Thus,
depending on the cellular context, physiologically regulated proteasome
activity could participate in the control of endogenous AHR functions.
*
Corresponding author. Mailing address: Departamento de
Bioquímica y Biología Molecular y Genética
Facultad de Ciencias, Universidad de Extremadura, Avda. de Elvas s/n,
06071 Badajoz, Spain. Phone: 34 924 289300, ext. 6867. Fax: 34 924 289419. E-mail: pmfersal{at}unex.es.
Molecular and Cellular Biology, March 2001, p. 1700-1709, Vol. 21, No. 5
0270-7306/01/$04.00+0 DOI: 10.1128/MCB.21.5.1700-1709.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Carvajal-Gonzalez, J. M., Roman, A. C., Cerezo-Guisado, M. I., Rico-Leo, E. M., Martin-Partido, G., Fernandez-Salguero, P. M.
(2009). Loss of dioxin-receptor expression accelerates wound healing in vivo by a mechanism involving TGF{beta}. J. Cell Sci.
122: 1823-1833
[Abstract]
[Full Text]
-
Carvajal-Gonzalez, J. M., Mulero-Navarro, S., Roman, A. C., Sauzeau, V., Merino, J. M., Bustelo, X. R., Fernandez-Salguero, P. M.
(2009). The Dioxin Receptor Regulates the Constitutive Expression of the Vav3 Proto-Oncogene and Modulates Cell Shape and Adhesion. Mol. Biol. Cell
20: 1715-1727
[Abstract]
[Full Text]
-
Roman, A. C., Benitez, D. A., Carvajal-Gonzalez, J. M., Fernandez-Salguero, P. M.
(2008). Genome-wide B1 retrotransposon binds the transcription factors dioxin receptor and Slug and regulates gene expression in vivo. Proc. Natl. Acad. Sci. USA
105: 1632-1637
[Abstract]
[Full Text]
-
Pollenz, R. S.
(2007). Comments on "Calpain Mediates the Dioxin-Induced Activation and Down-Regulation of the Aryl Hydrocarbon Receptor". Mol. Pharmacol.
71: 384-385
[Full Text]
-
Mulero-Navarro, S., Pozo-Guisado, E., Perez-Mancera, P. A., Alvarez-Barrientos, A., Catalina-Fernandez, I., Hernandez-Nieto, E., Saenz-Santamaria, J., Martinez, N., Rojas, J. M., Sanchez-Garcia, I., Fernandez-Salguero, P. M.
(2005). Immortalized Mouse Mammary Fibroblasts Lacking Dioxin Receptor Have Impaired Tumorigenicity in a Subcutaneous Mouse Xenograft Model. J. Biol. Chem.
280: 28731-28741
[Abstract]
[Full Text]
-
Kann, S., Huang, M.-y., Estes, C., Reichard, J. F., Sartor, M. A., Xia, Y., Puga, A.
(2005). Arsenite-Induced Aryl Hydrocarbon Receptor Nuclear Translocation Results in Additive Induction of Phase I Genes and Synergistic Induction of Phase II Genes. Mol. Pharmacol.
68: 336-346
[Abstract]
[Full Text]
-
Oesch-Bartlomowicz, B., Huelster, A., Wiss, O., Antoniou-Lipfert, P., Dietrich, C., Arand, M., Weiss, C., Bockamp, E., Oesch, F.
(2005). Aryl hydrocarbon receptor activation by cAMP vs. dioxin: Divergent signaling pathways. Proc. Natl. Acad. Sci. USA
102: 9218-9223
[Abstract]
[Full Text]
-
Tanaka, G., Kanaji, S., Hirano, A., Arima, K., Shinagawa, A., Goda, C., Yasunaga, S., Ikizawa, K., Yanagihara, Y., Kubo, M., Kuriyama-Fujii, Y., Sugita, Y., Inokuchi, A., Izuhara, K.
(2005). Induction and activation of the aryl hydrocarbon receptor by IL-4 in B cells. Int Immunol
17: 797-805
[Abstract]
[Full Text]
-
Gharavi, N., El-Kadi, A. O. S.
(2005). tert-BUTYLHYDROQUINONE IS A NOVEL ARYL HYDROCARBON RECEPTOR LIGAND. Drug Metab. Dispos.
33: 365-372
[Abstract]
[Full Text]
-
Chen, S., Operana, T., Bonzo, J., Nguyen, N., Tukey, R. H.
(2005). ERK Kinase Inhibition Stabilizes the Aryl Hydrocarbon Receptor: IMPLICATIONS FOR TRANSCRIPTIONAL ACTIVATION AND PROTEIN DEGRADATION. J. Biol. Chem.
280: 4350-4359
[Abstract]
[Full Text]
-
Joiakim, A., Mathieu, P. A., Elliott, A. A., Reiners, J. J. Jr.
(2004). Superinduction of CYP1A1 in MCF10A Cultures by Cycloheximide, Anisomycin, and Puromycin: A Process Independent of Effects on Protein Translation and Unrelated to Suppression of Aryl Hydrocarbon Receptor Proteolysis by the Proteasome. Mol. Pharmacol.
66: 936-947
[Abstract]
[Full Text]
-
Santiago-Josefat, B., Mulero-Navarro, S., Dallas, S. L., Fernandez-Salguero, P. M.
(2004). Overexpression of latent transforming growth factor-{beta} binding protein 1 (LTBP-1) in dioxin receptor-null mouse embryo fibroblasts. J. Cell Sci.
117: 849-859
[Abstract]
[Full Text]
-
Tsuchiya, Y., Nakajima, M., Yokoi, T.
(2003). Critical Enhancer Region to Which AhR/ARNT and Sp1 Bind in the Human CYP1B1 Gene. J Biochem
133: 583-592
[Abstract]
[Full Text]
-
Chauchereau, A., Amazit, L., Quesne, M., Guiochon-Mantel, A., Milgrom, E.
(2003). Sumoylation of the Progesterone Receptor and of the Steroid Receptor Coactivator SRC-1. J. Biol. Chem.
278: 12335-12343
[Abstract]
[Full Text]
-
Deroo, B. J., Rentsch, C., Sampath, S., Young, J., DeFranco, D. B., Archer, T. K.
(2002). Proteasomal Inhibition Enhances Glucocorticoid Receptor Transactivation and Alters Its Subnuclear Trafficking. Mol. Cell. Biol.
22: 4113-4123
[Abstract]
[Full Text]
-
Wang, S., Hankinson, O.
(2002). Functional Involvement of the Brahma/SWI2-related Gene 1 Protein in Cytochrome P4501A1 Transcription Mediated by the Aryl Hydrocarbon Receptor Complex. J. Biol. Chem.
277: 11821-11827
[Abstract]
[Full Text]