Hyungjin KimDonniphat DejsuphongGuillaume AdelmantRaphael CeccaldiKailin YangJarrod A. MartoAlan D. D'AndreaDana-Farber Cancer InstituteHarvard Medical SchoolMahidol UniversityCleveland Clinic Foundation2018-11-092018-11-092014-04-10Molecular Cell. Vol.54, No.1 (2014), 107-11810974164109727652-s2.0-84898043561https://repository.li.mahidol.ac.th/handle/20.500.14594/33278Timely DNA replication across damaged DNA is critical for maintaining genomic integrity. Translesion DNA synthesis (TLS) allows bypass of DNA lesions using error-prone TLS polymerases. The E3 ligase RAD18 is necessary for proliferating cell nuclear antigen (PCNA) monoubiquitination and TLS polymerase recruitment; however, the regulatory steps upstream of RAD18 activation are less understood. Here, we show that the UBZ4 domain-containing transcriptional repressor ZBTB1 is a critical upstream regulator of TLS. The UBZ4 motif is required for PCNA monoubiquitination and survival after UV damage. ZBTB1 associates with KAP-1, a transcriptional repressor whose phosphorylation relaxes chromatin after DNA damage. ZBTB1 depletion impairs formation of phospho-KAP-1 at UV damage sites and reduces RAD18 recruitment. Furthermore, phosphorylation of KAP-1 is necessary for efficient PCNA modification. We propose that ZBTB1 is required for localizing phospho-KAP-1 to chromatin and enhancing RAD18 accessibility. Collectively, our study implicates a ubiquitin-binding protein in orchestrating chromatin remodeling during DNA repair. © 2014 Elsevier Inc.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyArticleSCOPUS10.1016/j.molcel.2014.02.017