This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Li, J. Articles by Wani, A. A. Search for Related Content PubMed PubMed Citation Articles by Li, J. Articles by Wani, A. A.

DNA Damage Binding Protein Component DDB1 Participates in Nucleotide Excision Repair through DDB2 DNA-binding and Cullin 4A Ubiquitin Ligase Activity

Departments of ¹ Radiology and ² Molecular and Cellular Biochemistry, and ³ Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio

Requests for reprints: Altaf A. Wani, Department of Radiology, The Ohio State University, 2001 Polaris Parkway, Columbus, OH 43240. Phone: 614-293-0865; Fax: 614-293-0802; E-mail: wani.2{at}osu.edu.

Functional defect in DNA damage binding (DDB) activity has a direct relationship to decreased nucleotide excision repair (NER) and increased susceptibility to cancer. DDB forms a complex with cullin 4A (Cul4A), which is now known to ubiquitylate DDB2, XPC, and histone H2A. However, the exact role of DDB1 in NER is unclear. In this study, we show that DDB1 knockdown in human cells impaired their ability to efficiently repair UV-induced cyclobutane pyrimidine dimers (CPD) but not 6-4 photoproducts (6-4PP). Extensive nuclear protein fractionation and chromatin association analysis revealed that upon irradiation, DDB1 protein is translocated from a loosely bound to a tightly bound in vivo chromatin fraction and the DDB1 translocation required the participation of functional DDB2 protein. DDB1 knockdown also affected the translocation of Cul4A component to the tightly bound form in UV-damaged chromatin in vivo as well as its recruitment to the locally damaged nuclear foci in situ. However, DDB1 knockdown had no effect on DNA damage binding capacity of DDB2. The data indicated that DDB2 can bind to damaged DNA in vivo as a monomer, whereas Cul4A recruitment to damage sites depends on the fully assembled complex. Our data also showed that DDB1 is required for the UV-induced DDB2 ubiquitylation and degradation. In summary, the results suggest that (a) DDB1 is critical for efficient NER of CPD; (b) DDB1 acts in bridging DDB2 and ubiquitin ligase Cul4A; and (c) DDB1 aids in recruiting the ubiquitin ligase activity to the damaged sites for successful commencement of lesion processing by NER. (Cancer Res 2006; 66(17): 8590-7)

This article has been cited by other articles:

				Q. Zhao, Q.-E. Wang, A. Ray, G. Wani, C. Han, K. Milum, and A. A. Wani Modulation of Nucleotide Excision Repair by Mammalian SWI/SNF Chromatin-remodeling Complex J. Biol. Chem., October 30, 2009; 284(44): 30424 - 30432. [Abstract] [Full Text] [PDF]

				S. Alekseev, M. S. Luijsterburg, A. Pines, B. Geverts, P.-O. Mari, G. Giglia-Mari, H. Lans, A. B. Houtsmuller, L. H. F. Mullenders, J. H. J. Hoeijmakers, et al. Cellular Concentrations of DDB2 Regulate Dynamic Binding of DDB1 at UV-Induced DNA Damage Mol. Cell. Biol., December 15, 2008; 28(24): 7402 - 7413. [Abstract] [Full Text] [PDF]

				Q. Zhao, B. M. Barakat, S. Qin, A. Ray, M. A. El-Mahdy, G. Wani, E.-S. Arafa, S. N. Mir, Q.-E. Wang, and A. A. Wani The p38 Mitogen-activated Protein Kinase Augments Nucleotide Excision Repair by Mediating DDB2 Degradation and Chromatin Relaxation J. Biol. Chem., November 21, 2008; 283(47): 32553 - 32561. [Abstract] [Full Text] [PDF]

				L. Tan, E. Ehrlich, and X.-F. Yu DDB1 and Cul4A Are Required for Human Immunodeficiency Virus Type 1 Vpr-Induced G2 Arrest J. Virol., October 1, 2007; 81(19): 10822 - 10830. [Abstract] [Full Text] [PDF]

				M. S. Luijsterburg, J. Goedhart, J. Moser, H. Kool, B. Geverts, A. B. Houtsmuller, L. H. F. Mullenders, W. Vermeulen, and R. van Driel Dynamic in vivo interaction of DDB2 E3 ubiquitin ligase with UV-damaged DNA is independent of damage-recognition protein XPC J. Cell Sci., August 1, 2007; 120(15): 2706 - 2716. [Abstract] [Full Text] [PDF]

				W. M. Al Khateeb and D. F. Schroeder DDB2, DDB1A and DET1 Exhibit Complex Interactions During Arabidopsis Development Genetics, May 1, 2007; 176(1): 231 - 242. [Abstract] [Full Text] [PDF]