Functional characterization of TIP60 sumoylation in UV-irradiated DNA damage response.
The histone acetyltransferase TIP60 regulates the DNA damage response following genotoxic stress by acetylating histone and remodeling chromatin. However, the molecular mechanisms underlying the TIP60-dependent response to UV-induced DNA damage remain poorly understood. To systematically analyse proteins that regulate TIP60 activity in response to UV irradiation, we performed a proteomic ... analysis of proteins selectively bound to TIP60 in response to UV irradiation using mass spectrometry and identified a novel regulatory mechanism by which TIP60 orchestrates transcriptional activation of p53-dependent checkpoint response in UV-irradiated cells. The initial step of this pathway involves UV-induced association of TIP60 with SUMO-conjugation enzymes and site-specific sumoylation of TIP60 at lysines 430 and 451 via Ubc9. This sumoylation initiates the relocation of TIP60 from nucleoplasm to the promyelocytic leukemia body, which is essential for the UV-irradiated DNA damage repair response via a p53-dependent pathway. Significantly, inhibition of TIP60 sumoylation by overexpression of non-sumoylatable mutant abrogates the p53-dependent DNA damage response, demonstrating the importance of TIP60 sumoylation in response to UV irradiation. Our biochemical characterization demonstrated that the sumoylation of TIP60 augments its acetyltransferase activity in vitro and in vivo. Thus, this study shed new light on the function and regulation of TIP60 activity in UV-irradiated DNA damage response.
Mesh Terms:
Bone Neoplasms, Cell Nucleus, Cells, Cultured, Cysteine Endopeptidases, DNA Damage, Electrophoresis, Polyacrylamide Gel, HeLa Cells, Histone Acetyltransferases, Humans, Kidney, Lysine, Mass Spectrometry, Osteosarcoma, Protein Processing, Post-Translational, Proteomics, RNA, Small Interfering, SUMO-1 Protein, Small Ubiquitin-Related Modifier Proteins, Tumor Suppressor Protein p53, Ubiquitin-Conjugating Enzymes, Ultraviolet Rays
Bone Neoplasms, Cell Nucleus, Cells, Cultured, Cysteine Endopeptidases, DNA Damage, Electrophoresis, Polyacrylamide Gel, HeLa Cells, Histone Acetyltransferases, Humans, Kidney, Lysine, Mass Spectrometry, Osteosarcoma, Protein Processing, Post-Translational, Proteomics, RNA, Small Interfering, SUMO-1 Protein, Small Ubiquitin-Related Modifier Proteins, Tumor Suppressor Protein p53, Ubiquitin-Conjugating Enzymes, Ultraviolet Rays
Oncogene
Date: Feb. 07, 2008
PubMed ID: 17704809
View in: Pubmed Google Scholar
Download Curated Data For This Publication
131490
Switch View:
- Interactions 15