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Paper: The ubiquitous role of ubiquitin in the DNA damage response (doi:10.1016/j.dnarep.2010.09.011) Ubiquitination can lead to: 1. conformational changes 2. cellular localization 3. enzymatic activity 4. protein-protein interaction 5. life time of protein Purpose of this review: To inform the relationship between ubiquitination and DNA repair and checkpoint control Now it changes to 3 types (E3 ubiquitin ligase): 1. HECT 2. RBR 3. RING type Monoubiquitylation 1. endocytosis 2. DNA repair and replication 3. Transcriptional regulation and modulation of histone code Ubiquitin has 7 lysine Small Ubiquitin-like Modifier (or SUMO)  proteins are a family of small proteins that are covalently attached to and detached from other proteins in cells to modify their function DSB occur --  1. the franking chromatin on the DSB -- sites for recruiting the DNA repair factors -- cause the foci phenotype 2. Foci formation is the results of ubiquitylation ...

Paper: RNF8- and RNF168-dependent degradation of KDM4A/JMJD2A triggers 53BP1 recruitment to DNA damage sites (doi:10.1038/emboj.2012.47) Recruitment of 53BP1 relies on 1. ubiquitination activity of RNF8-RNF168 2. methylation of histone H4 on K20 ---- Research gap: No molecular detail on how 53BP1 get access to the methylated histone H4 ---- Findings: 1. JMJD2A(KDM4A) binds the methylated histone 2. JMJD2A is degraded by proteasome through the RNF8 mechanism 3. Abnormal expression, JMJD2 hinds the methylated H4 from 53BP1on the damage site  - reflect JMJD2A mask the accessibility  of 53BP1 to methylated H4 4. Lacking of RNF8+RNF168 -- plus reduce level of JMJD2A + JMJD2B - rescue 53BP1 foci ---- Conclusion: RNF8 control the accessibility of 53BP1 through the degradation of JMJD2A, by adding the ubiquitin tag on it ---- Remarks: Cell line use: U2OS (Human osteosarcoma cells)

Paper: RNF8 Ubiquitylates Histones at DNA Double-Strand Breaks and Promotes Assembly of Repair Proteins (http://dx.doi.org/10.1016/j.cell.2007.09.040) Conclusion for my own study on RING-finger protein in DNA repair; General overview: DNA repair is important to maintain genome integrity Research question: The mechanisms of proteins retention at db strand break is not clear -- that is why they want to study how the dbDNA is recognized Results: 1. RNF8 is recruited to the DSB via the interaction between FHA domain at N-terminal vs P-MDC1 2. Increase in DSB Ubiquitinylation (when knock down-RNF8 or disrupt the RING/FHA domain reduce DSB associated ubiquitinylation) 3. Recruitment of 53BP1 and BRCA1 (when knock down-RNF8 or disrupt the RING/FHA domain reduce the retention of those two proteins) 4. RNF8 is important for IR-induced damage 5. RNF8 protect genome integrity by issuing chromatin that franks the DNA db strand break --- Remarks: Cell line using in this stud...