Plays a key role in the repair of double-strand DNA breaks (DSBs) in response to DNA damage by promoting non-homologous end joining (NHEJ)-mediated repair of DSBs and specifically counteracting the function of the homologous recombination (HR) repair protein BRCA1.
基因名
TP53BP1
蛋白名
TP53-binding protein 1
亚基
Interacts with IFI202A (By similarity). Binds to the central domain of p53/TP53. May form homooligomers. Interacts with DCLRE1C. Interacts with histone H2AFX and this requires phosphorylation of H2AFX on 'Ser-139'. Interacts with histone H4 that has been dimethylated at 'Lys-20' (H4K20me2). Has low affinity for histone H4 containing monomethylated 'Lys-20' (H4K20me1). Does not bind histone H4 containing unmethylated or trimethylated 'Lys-20' (H4K20me3). Has low affinity for histone H3 that has been dimethylated on 'Lys-79'. Has very low affinity for histone H3 that has been monomethylated on 'Lys-79' (in vitro). Does not bind unmethylated histone H3. Interacts with MUM1/EXPAND1. Interacts with CHEK2; modulates CHEK2 phosphorylation at 'Thr-68' in response to infrared. Interacts with MSL1; this interaction may be required for MSL1 DNA repair activity, but not for histone acetyltransferase activity.
亚细胞定位
Nucleus. Chromosome; centromere; kinetochore. Associated with kinetochores. Both nuclear and cytoplasmic in some cells. Recruited to sites of DNA damage, such as double stand breaks. Methylation of histone H4 at 'Lys-20' is required for efficient localization to double strand breaks.
翻译后修饰
Asymmetrically dimethylated on Arg residues by PRMT1. Methylation is required for DNA binding.
Phosphorylated at basal level in the absence of DNA damage. Hyper-phosphorylated in an ATM-dependent manner in response to DNA damage induced by ionizing radiation. Hyper-phosphorylated in an ATR-dependent manner in response to DNA damage induced by UV irradiation.
疾病
Note=A chromosomal aberration involving TP53BP1 is found in a form of myeloproliferative disorder chronic with eosinophilia. Translocation t(5;15)(q33;q22) with PDGFRB creating a TP53BP1-PDGFRB fusion protein.
相似性
Contains 2 BRCT domains.
功能
May have a role in checkpoint signaling during mitosis. Enhances TP53-mediated transcriptional activation. Plays a role in the response to DNA damage.