This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Teo, A. K. C.
Right arrow Articles by Li, B. F. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Teo, A. K. C.
Right arrow Articles by Li, B. F. L.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, October 2001, p. 7105-7114, Vol. 21, No. 20
0270-7306/01/$04.00+0   DOI: 10.1128/MCB.21.20.7105-7114.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

The Modified Human DNA Repair Enzyme O6-Methylguanine-DNA Methyltransferase Is a Negative Regulator of Estrogen Receptor-Mediated Transcription upon Alkylation DNA Damage

Alvin K. C. Teo, Hue Kian Oh, Rahmen B. Ali, and Benjamin F. L. Li*

Chemical Carcinogenesis Laboratory, Institute of Molecular and Cell Biology, National University of Singapore, Singapore 117609, Republic of Singapore

Received 22 March 2001/Returned for modification 25 April 2001/Accepted 16 July 2001

Cell proliferation requires precise control to prevent mutations from replication of (unrepaired) damaged DNA in cells exposed spontaneously to mutagens. Here we show that the modified human DNA repair enzyme O6-methylguanine-DNA methyltransferase (R-MGMT), formed from the suicidal repair of the mutagenic O6-alkylguanine (6RG) lesions by MGMT in the cells exposed to alkylating carcinogens, functions in such control by preventing the estrogen receptor (ER) from transcription activation that mediates cell proliferation. This function is in contrast to the phosphotriester repair domain of bacterial ADA protein, which acts merely as a transcription activator for its own synthesis upon repair of phosphotriester lesions. First, MGMT, which is constitutively present at active transcription sites, coprecipitates with the transcription integrator CREB-binding protein CBP/p300 but not R-MGMT. Second, R-MGMT, which adopts an altered conformation, utilizes its exposed VLWKLLKVV peptide domain (codons 98 to 106) to bind ER. This binding blocks ER from association with the LXXLL motif of its coactivator, steroid receptor coactivator-1, and thus represses ER effectively from carrying out transcription that regulates cell growth. Thus, through a change in conformation upon repair of the 6RG lesion, MGMT switches from a DNA repair factor to a transcription regulator (R-MGMT), enabling the cell to sense as well as respond to mutagens. These results have implications in chemotherapy and provide insights into the mechanisms for linking transcription suppression with transcription-coupled DNA repair.


* Corresponding author. Mailing address: Chemical Carcinogenesis Laboratory, Institute of Molecular and Cell Biology, National University of Singapore, 30 Medical Dr., Singapore 117609, Republic of Singapore. Phone: (65) 874 3763 or (65) 874 3797. Fax: (65) 779 1117 or (65) 775 9582. E-mail: mcblib{at}imcb.nus.edu.sg.


Molecular and Cellular Biology, October 2001, p. 7105-7114, Vol. 21, No. 20
0270-7306/01/$04.00+0   DOI: 10.1128/MCB.21.20.7105-7114.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Remington, M., Chtchetinin, J., Ancheta, K., Nghiemphu, P. L., Cloughesy, T., Lai, A. (2009). The L84F polymorphic variant of human O6-methylguanine-DNA methyltransferase alters stability in U87MG glioma cells but not temozolomide sensitivity. Neuro Oncol 11: 22-32 [Abstract] [Full Text]  
  • Verbeek, B., Southgate, T. D., Gilham, D. E., Margison, G. P. (2008). O6-Methylguanine-DNA methyltransferase inactivation and chemotherapy. Br Med Bull 85: 17-33 [Abstract] [Full Text]  
  • Curtis, C. D., Likhite, V. S., McLeod, I. X., Yates, J. R., Nardulli, A. M. (2007). Interaction of the Tumor Metastasis Suppressor Nonmetastatic Protein 23 Homologue H1 and Estrogen Receptor {alpha} Alters Estrogen-Responsive Gene Expression. Cancer Res. 67: 10600-10607 [Abstract] [Full Text]  
  • Schultz-Norton, J. R., Walt, K. A., Ziegler, Y. S., McLeod, I. X., Yates, J. R., Raetzman, L. T., Nardulli, A. M. (2007). The Deoxyribonucleic Acid Repair Protein Flap Endonuclease-1 Modulates Estrogen-Responsive Gene Expression. Mol. Endocrinol. 21: 1569-1580 [Abstract] [Full Text]  
  • Han, J., Hankinson, S. E., Vivo, I. D. (2006). Polymorphisms in O6-methylguanine DNA methyltransferase and endometrial cancer risk. Carcinogenesis 27: 2281-2285 [Abstract] [Full Text]  
  • Shen, J., Terry, M. B., Gammon, M. D., Gaudet, M. M., Teitelbaum, S. L., Eng, S. M., Sagiv, S. K., Neugut, A. I., Santella, R. M. (2005). MGMT genotype modulates the associations between cigarette smoking, dietary antioxidants and breast cancer risk. Carcinogenesis 26: 2131-2137 [Abstract] [Full Text]  
  • Lucey, M. J., Chen, D., Lopez-Garcia, J., Hart, S. M., Phoenix, F., Al-Jehani, R., Alao, J. P., White, R., Kindle, K. B., Losson, R., Chambon, P., Parker, M. G., Schar, P., Heery, D. M., Buluwela, L., Ali, S. (2005). T:G mismatch-specific thymine-DNA glycosylase (TDG) as a coregulator of transcription interacts with SRC1 family members through a novel tyrosine repeat motif. Nucleic Acids Res 33: 6393-6404 [Abstract] [Full Text]  
  • Margison, G. P., Povey, A. C., Kaina, B., Santibanez Koref, M. F. (2003). Variability and regulation of O6-alkylguanine-DNA alkyltransferase. Carcinogenesis 24: 625-635 [Abstract] [Full Text]  
  • Chuang, L. S.-H., Tan, E. H.-H., Oh, H.-K., Li, B. F-L. (2002). Selective Depletion of Human DNA-Methyltransferase DNMT1 Proteins by Sulfonate-derived Methylating Agents. Cancer Res. 62: 1592-1597 [Abstract] [Full Text]