Article (Scientific journals)
Interaction of retroviral Tax oncoproteins with tristetraprolin and regulation of tumor necrosis factor-alpha expression.
Twizere, Jean-Claude; Kruys, Veronique; Lefebvre, Laurent et al.
2003In Journal of the National Cancer Institute, 95 (24), p. 1846-59
Peer Reviewed verified by ORBi
 

Files


Full Text
Twizere et al 2003.pdf
Publisher postprint (953.9 kB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Animals; Cattle; DNA, Complementary/analysis; DNA-Binding Proteins; Gene Expression Regulation, Neoplastic; Gene Products, tax/metabolism; Human T-lymphotropic virus 1; Humans; Immediate-Early Proteins/genetics/metabolism; Leukemia Virus, Bovine; Microscopy, Confocal; Mutation; Neoplasms/metabolism/virology; Plasmids; Polymerase Chain Reaction; Precipitin Tests; Transfection; Tristetraprolin; Tumor Necrosis Factor-alpha/metabolism; Up-Regulation; beta-Galactosidase/metabolism
Abstract :
[en] BACKGROUND: The Tax oncoproteins are transcriptional regulators of viral expression involved in pathogenesis induced by complex leukemogenic retroviruses (or delta-retroviruses, i.e., primate T-cell leukemia viruses and bovine leukemia virus). To better understand the molecular pathways leading to cell transformation, we aimed to identify cellular proteins interacting with Tax. METHODS: We used a yeast two-hybrid system to identify interacting cellular proteins. Interactions between Tax and candidate interacting cellular proteins were confirmed by glutathione S-transferase (GST) pulldown assays, co-immunoprecipitation, and confocal microscopy. Functional interactions between Tax and one interacting protein, tristetraprolin (TTP), were assessed by analyzing the expression of tumor necrosis factor-alpha (TNF-alpha), which is regulated by TTP, in mammalian cells (HeLa, D17, HEK 293, and RAW 264.7) transiently transfected with combinations of intact and mutant Tax and TTP. RESULTS: We obtained seven interacting cellular proteins, of which one, TTP, was further characterized. Tax and TTP were found to interact specifically through their respective carboxyl-terminal domains. The proteins colocalized in the cytoplasm in a region surrounding the nucleus of HeLa cells. Furthermore, coexpression of Tax was associated with nuclear accumulation of TTP. TTP is an immediate-early protein that inhibits expression of TNF-alpha at the post-transcriptional level. Expression of Tax reverted this inhibition, both in transient transfection experiments and in stably transfected macrophage cell lines. CONCLUSION: Tax, through its interactions with the TTP repressor, indirectly increases TNF-alpha expression. This observation is of importance for the cell transformation process induced by leukemogenic retroviruses, because TNF-alpha overexpression plays a central role in pathogenesis.
Disciplines :
Oncology
Biochemistry, biophysics & molecular biology
Author, co-author :
Twizere, Jean-Claude  ;  Université de Liège - ULiège > Gembloux Agro-Bio Tech > Gembloux Agro-Bio Tech
Kruys, Veronique
Lefebvre, Laurent
Vanderplasschen, Alain ;  Université de Liège - ULiège > Immunologie et vaccinologie
Collete, Delphine
Debacq, Christophe
Lai, Wi S
Jauniaux, Jean-Claude
Bernstein, Lori R
Semmes, O John
Burny, Arsène ;  Université de Liège - ULiège > Agro Biotech Gembloux
Blackshear, Perry J
Kettmann, Richard ;  Université de Liège - ULiège > Gembloux Agro-Bio Tech > Gembloux Agro-Bio Tech
Willems, Luc  ;  Université de Liège - ULiège > GIGA-Research - Gembloux Agro-Bio Tech
More authors (4 more) Less
Language :
English
Title :
Interaction of retroviral Tax oncoproteins with tristetraprolin and regulation of tumor necrosis factor-alpha expression.
Publication date :
2003
Journal title :
Journal of the National Cancer Institute
ISSN :
0027-8874
eISSN :
1460-2105
Publisher :
Oxford University Press, Cary, United States - North Carolina
Volume :
95
Issue :
24
Pages :
1846-59
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 25 November 2010

Statistics


Number of views
84 (1 by ULiège)
Number of downloads
35 (1 by ULiège)

Scopus citations®
 
49
Scopus citations®
without self-citations
30
OpenCitations
 
42

Bibliography


Similar publications



Contact ORBi