NYMC Faculty Publications
Identification of RNF8 as a Ubiquitin Ligase Involved in Targeting the p12 Subunit of DNA Polymerase δ for Degradation in Response to DNA Damage
Author Type(s)
Faculty
DOI
10.1074/jbc.M112.423392
Journal Title
The Journal of Biological Chemistry
First Page
2941
Last Page
2950
Document Type
Article
Publication Date
2-1-2013
Department
Biochemistry and Molecular Biology
Keywords
Animals, DNA Damage, DNA Polymerase III, DNA-Binding Proteins, Half-Life, HeLa Cells, Histones, Humans, Mice, Mice, Knockout, Models, Biological, Polyubiquitin, Protein Transport, Proteolysis, RNA, Small Interfering, Recombinant Fusion Proteins, Subcellular Fractions, Ubiquitin-Conjugating Enzymes, Ubiquitin-Protein Ligases, Ubiquitination, Ultraviolet Rays
Disciplines
Medicine and Health Sciences
Abstract
DNA polymerase δ consists of four subunits, one of which, p12, is degraded in response to DNA damage through the ubiquitin-proteasome pathway. However, the identities of the ubiquitin ligase(s) that are responsible for the proximal biochemical events in triggering proteasomal degradation of p12 are unknown. We employed a classical approach to identifying a ubiquitin ligase that is involved in p12 degradation. Using UbcH5c as ubiquitin-conjugating enzyme, a ubiquitin ligase activity that polyubiquitinates p12 was purified from HeLa cells. Proteomic analysis revealed that RNF8, a RING finger ubiquitin ligase that plays an important role in the DNA damage response, was the only ubiquitin ligase present in the purified preparation. In vivo, DNA damage-induced p12 degradation was significantly reduced by shRNA knockdown of RNF8 in cultured human cells and in RNF8(-/-) mouse epithelial cells. These studies provide the first identification of a ubiquitin ligase activity that is involved in the DNA damage-induced destruction of p12. The identification of RNF8 allows new insights into the integration of the control of p12 degradation by different DNA damage signaling pathways.
Recommended Citation
Zhang, S., Zhou, Y., Sarkeshik, A., Yates, J. R., Thomson, T. M., Zhang, Z., Lee, E. Y., & Lee, M. Y. (2013). Identification of RNF8 as a Ubiquitin Ligase Involved in Targeting the p12 Subunit of DNA Polymerase δ for Degradation in Response to DNA Damage. The Journal of Biological Chemistry, 288 (5), 2941-2950. https://doi.org/10.1074/jbc.M112.423392
