title: The histone H2A deubiquitinase USP16 interacts with HERC2 and fine-tunes cellular response to DNA damage.
abstract: Histone ubiquitination at DNA double strand breaks facilitates the recruitment of downstream repair proteins; however, how the ubiquitination is dynamically regulated during repair and terminated after repair is not well understood. Here we report that the histone H2A deubiquitinase USP16 interacts with HERC2, fine-tunes the ubiquitin signal during repair, and importantly, is required for terminating the ubiquitination signal after repair. HERC2 interacts with the coiled-coil domain of USP16 through its C-terminal HECT domain. HERC2 knockdown affects the levels of ubiquitinated H2A through the action of USP16. In response to DNA damage, USP16 levels increase, and this increase is dependent on HERC2. Increased USP16 serves as a negative regulator for DNA damage-induced ubiquitin foci formation and affects downstream factor recruitment and DNA damage response. The functional significance of USP16 is further manifested in human Down syndrome patient cells, which contain three copies of USP16 genes and have altered cellular response to DNA damage. Finally, we demonstrated that USP16 could deubiquitinate both H2A Lys-119 and H2A Lys-15 ubiquitination in vitro. Therefore, this study identifies USP16 as a critical regulator of DNA damage response and H2A Lys-15 ubiquitination as a potential target of USP16.
authors.affiliation: From the Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294 and.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: From the Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294 and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Huirong
authors.initials: H
authors.lastname: Yang
authors.affiliation: From the Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, Alabama 35294 and hbwang@uab.edu.
authors.forename: Hengbin
authors.initials: H
authors.lastname: Wang
mesh_terms: D015153:Blotting, Western; D045744:Cell Line, Tumor; D004249:DNA Damage; D004260:DNA Repair; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics / Q000378:metabolism*; D057809:HEK293 Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D008239:Lysine / Q000378:metabolism; D008856:Microscopy, Fluorescence; D011485:Protein Binding; D034622:RNA Interference; D015398:Signal Transduction; D025801:Ubiquitin / Q000378:metabolism; D043222:Ubiquitin Thiolesterase / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism; D064570:Ubiquitin-Specific Proteases / Q000235:genetics / Q000378:metabolism; D054875:Ubiquitination
chemical_list: D020662:Guanine Nucleotide Exchange Factors; D006657:Histones; C118778:USP16 protein, human; D025801:Ubiquitin; C118566:HERC2 protein, human; D044767:Ubiquitin-Protein Ligases; D043222:Ubiquitin Thiolesterase; D064570:Ubiquitin-Specific Proteases; D008239:Lysine
keywords: DNA Damage; Deubiquitylation (Deubiquitination); Histone; Ubiquitin Ligase; Ubiquitylation (Ubiquitination)