atm inhibitor  (MedChemExpress)

Journal: Clinical and Translational Medicine

Article Title: ROS‐ATM‐CBP axis‐mediated PARP1 lactylation aggravates doxorubicin‐induced cardiotoxicity

doi: 10.1002/ctm2.70745

Figure Lengend Snippet: ROS‐ATM‐CBP signalling pathway activates PARP1 lactylation. (A, B) Intracellular ROS and lactate levels in HL‐1 cells treated with 1 µM doxorubicin for 0, 2 and 4 h. (C) Representative immunoprecipitation, western blots and quantification for detecting PARP1 lactylation. HL‐1 cells were stimulated by doxorubicin (1 µM for 0, 2 and 4 h), and the cells were lysed and immunoprecipitated using an anti‐PARP1 antibody, followed by detection of Pan‐KLA. (D) Schematic of the effect of SIRT1 activation on the lactylation level of PARP1 in mice. DOX (5 mg/kg) or the same volume of saline was administered intraperitoneally once weekly. One week before the DOX treatment, mice were pre‐treated with resveratrol (SIRT1 activator, 10 mg/kg/day) via daily intraperitoneal injections. (E) The SIRT1 activity was detected. (F–H) Representative immunoprecipitation, western blots and quantification for detecting PARP1 lactylation and protein expression of SIRT1. (I) Schematic of the effect of CBP inhibition on the lactylation level of PARP1 in mice. DOX (5 mg/kg) or the same volume of saline was administered intraperitoneally once weekly. One week before the DOX treatment, mice were pre‐treated with SGC‐CBP30 (CBP inhibitor, 15 mg/kg/day) via daily intraperitoneal injections. (J) The CBP activity was detected. (K–M) Representative immunoprecipitation, western blots and quantification for detecting PARP1 lactylation and protein expression of CBP. (A–C) Based on the central limit theorem, the data were considered to be normally distributed. Relative protein levels were calculated as fold changes vs the first group. Data are presented as mean ± SD. Statistical significance was assessed by one‐way ANOVA with Tukey multiple comparisons test ( P values adjusted for 3 comparisons). (D–M) Relative protein levels were calculated as fold changes vs. the first group. Data are presented as mean ± SD. Statistical significance was assessed by two‐way ANOVA with Bonferroni multiple comparisons test ( p ‐values adjusted for 9 comparisons). ns p > .05, * p < .05, ** p < .01, *** p < .001.

Article Snippet: ATM inhibitor (KU‐55933; #HY‐12016; 10 μM; 2 h); LDHA inhibitor (Galloflavin; #HY‐W040118; 10 −5 M; 24 h) and CBP activator (CTB; #HY‐134964; 10 −4 M; 24 h) were obtained from MedChemExpress.

Techniques: Immunoprecipitation, Western Blot, Activation Assay, Saline, Activity Assay, Expressing, Inhibition

Journal: Clinical and Translational Medicine

Article Title: ROS‐ATM‐CBP axis‐mediated PARP1 lactylation aggravates doxorubicin‐induced cardiotoxicity

doi: 10.1002/ctm2.70745

Figure Lengend Snippet: Model showing the molecular signalling cascade of CBP‐PARP1 lactylation–PARylation axis. The schematic depicts how oxidative stress‐induced ROS activates the ATM‐CBP‐PARP1 signalling pathway via a lactylation–PARylation cascade to promote cardiomyocyte apoptosis.

Article Snippet: ATM inhibitor (KU‐55933; #HY‐12016; 10 μM; 2 h); LDHA inhibitor (Galloflavin; #HY‐W040118; 10 −5 M; 24 h) and CBP activator (CTB; #HY‐134964; 10 −4 M; 24 h) were obtained from MedChemExpress.

Techniques:

Journal: Biochemistry and Biophysics Reports

Article Title: ATM inhibition restores IFN-γ sensitivity and induces ferroptosis in NSCLC via DNA damage response

doi: 10.1016/j.bbrep.2026.102568

Figure Lengend Snippet: Inhibition of ATM restores NSCLC cells to IFN-γ by inducing DNA damage response (A) Cell viability of A549 (left panel) or PC-9 (right panel) treated with IFN-γ (1000 ng/ml) and/or KU-55933 (10 μM) for 24 h are shown. Data are presented as mean ± SD. * p < 0.05. (B) Expression of γH2AX and b-Actin (loading control) in A549 (left panel) or PC-9 (right panel) cells treated with IFN-γ (1000 ng/ml) and/or KU-55933 (10 μM) for 24 h are shown.

Article Snippet: IFN-γ was purchased from Biolegend, and ATM inhibitor KU-55933 was purchased from MedChem Express.

Techniques: Inhibition, Expressing, Control

Journal: Biochemistry and Biophysics Reports

Article Title: ATM inhibition restores IFN-γ sensitivity and induces ferroptosis in NSCLC via DNA damage response

doi: 10.1016/j.bbrep.2026.102568

Figure Lengend Snippet: Inhibition of ATM in combination with IFN-γ induce ferroptosis in NSCLCs Cell viability of A549 (A) or PC-9 (B) treated with the indicated combination of IFN-γ (1000 ng/ml), KU-55933 (10 μM), Ferrostatin-1 (5 μM), and Liproxstatin-1 (5 μM) for 24 h are shown. Data are presented as mean ± SD. * p < 0.05.

Article Snippet: IFN-γ was purchased from Biolegend, and ATM inhibitor KU-55933 was purchased from MedChem Express.

Techniques: Inhibition

Journal: Biochemistry and Biophysics Reports

Article Title: ATM inhibition restores IFN-γ sensitivity and induces ferroptosis in NSCLC via DNA damage response

doi: 10.1016/j.bbrep.2026.102568

Figure Lengend Snippet: ATM inhibition in combination with IFN-γ alters glutathione metabolism in NSCLC Cells were treated with IFN-γ (1000 ng/mL) and/or KU-55933 (10 μM) for 24 h, and then the intracellular levels of GSH and GSSG were quantified. The results of total glutathione (A), GSH (B), GSSG (C), and GSH/GSSG ratio (D) are shown. * p < 0.05.

Article Snippet: IFN-γ was purchased from Biolegend, and ATM inhibitor KU-55933 was purchased from MedChem Express.

Techniques: Inhibition

Journal: Pharmaceuticals

Article Title: Potential Mechanisms of MAP Kinase JNK’s Involvement in Modulating Cancer Cell Fate in a Cisplatin Concentration-Dependent Manner

doi: 10.3390/ph19030509

Figure Lengend Snippet: Effects of ATM inhibition on cisplatin-treated A549 cell viability. Cell viability was measured via MTT assay after 72 h of treatment and normalized to baseline viability before treatment. DMSO—vehicle control (0.2%), SP—SP600125 (20 μM), KU—KU60019 (5 μM), and combo—SP + KU. Statistical significance is indicated by asterisks (n.s.—non-significant; ***— p < 0.0005; more details in the Methods and ).

Article Snippet: Other reagents: 99.5% dimethylsulphoxide DMSO (#7029.1) from Carl Roth, Karlsruhe, Germany; oxaliplatin (5 mg/mL infusion solution) from Fresenius Kabi Oncology Plc., Hampshire, UK; daunorubicin (#251800) and AKT inhibitor VIII (10 μM, #124018) from EMD Millipore/Merck, Billerica, MA, USA; ATM inhibitor KU60019 (5 μM, #S1570) and RAS inhibitor RMC-6236 (1 μM, #E1597) from Selleck Chemicals LLC, Houston, TX, USA; SP600125 (20 μM; #J67272) from Alpha Aesar, Ward Hill, MA, USA; capivasertib AZD5363 (10 μM; #15406) from Cayman Chemical, Ann Arbor, MI, USA.

Techniques: Inhibition, MTT Assay, Control

Journal: Pharmaceuticals

Article Title: Potential Mechanisms of MAP Kinase JNK’s Involvement in Modulating Cancer Cell Fate in a Cisplatin Concentration-Dependent Manner

doi: 10.3390/ph19030509

Figure Lengend Snippet: Induction of H2AX phosphorylation by cisplatin. ( a ) High concentration of cisplatin induces H2AX phosphorylation as early as 6 h after the treatment. ( b ) After 20 h, even very low concentrations of cisplatin induce H2AX phosphorylation. ( c ) ATM inhibitor reduces H2AX phosphorylation. DM—vehicle control DMSO (0.2%) and KU—KU60019 (5 μM). Representative Western blots are shown. Total protein stained with Coomassie dye in polyacrylamide gels serve as loading controls.

Article Snippet: Other reagents: 99.5% dimethylsulphoxide DMSO (#7029.1) from Carl Roth, Karlsruhe, Germany; oxaliplatin (5 mg/mL infusion solution) from Fresenius Kabi Oncology Plc., Hampshire, UK; daunorubicin (#251800) and AKT inhibitor VIII (10 μM, #124018) from EMD Millipore/Merck, Billerica, MA, USA; ATM inhibitor KU60019 (5 μM, #S1570) and RAS inhibitor RMC-6236 (1 μM, #E1597) from Selleck Chemicals LLC, Houston, TX, USA; SP600125 (20 μM; #J67272) from Alpha Aesar, Ward Hill, MA, USA; capivasertib AZD5363 (10 μM; #15406) from Cayman Chemical, Ann Arbor, MI, USA.

Techniques: Phospho-proteomics, Concentration Assay, Control, Western Blot, Staining

Journal: Pharmaceuticals

Article Title: Potential Mechanisms of MAP Kinase JNK’s Involvement in Modulating Cancer Cell Fate in a Cisplatin Concentration-Dependent Manner

doi: 10.3390/ph19030509

Figure Lengend Snippet: Effect of ATM kinase inhibition on p53 expression. ( a ) In A549 cells treated with 25 μM cisplatin (both alone and in combination with the JNK inhibitor SP600125), p53 expression is decreased after the addition of the ATM inhibitor KU60019 (KU, 5 μM). ( b ) In A549 cells exposed to 100 μM cisplatin and JNK inhibitor SP600125, ATM inhibitor KU decreases p53 expression. DM—vehicle control DMSO (0.2%), SP—SP600125 (20 μM); treatment duration—20 h. Representative Western blots are shown. Total protein stained with Coomassie dye in polyacrylamide gels serve as loading controls.

Article Snippet: Other reagents: 99.5% dimethylsulphoxide DMSO (#7029.1) from Carl Roth, Karlsruhe, Germany; oxaliplatin (5 mg/mL infusion solution) from Fresenius Kabi Oncology Plc., Hampshire, UK; daunorubicin (#251800) and AKT inhibitor VIII (10 μM, #124018) from EMD Millipore/Merck, Billerica, MA, USA; ATM inhibitor KU60019 (5 μM, #S1570) and RAS inhibitor RMC-6236 (1 μM, #E1597) from Selleck Chemicals LLC, Houston, TX, USA; SP600125 (20 μM; #J67272) from Alpha Aesar, Ward Hill, MA, USA; capivasertib AZD5363 (10 μM; #15406) from Cayman Chemical, Ann Arbor, MI, USA.

Techniques: Inhibition, Expressing, Control, Western Blot, Staining

Journal: Pharmaceuticals

Article Title: Potential Mechanisms of MAP Kinase JNK’s Involvement in Modulating Cancer Cell Fate in a Cisplatin Concentration-Dependent Manner

doi: 10.3390/ph19030509

Figure Lengend Snippet: Effect of ATM inhibition on protein kinase AKT phosphorylation. ( a ) In A549 cells treated with 25 μM cisplatin (both alone and in combination with the JNK inhibitor SP600125), AKT phosphorylation is decreased after the addition of the ATM inhibitor KU60019 (KU, 5 μM). ( b ) In A549 cells exposed to 100 μM cisplatin and JNK inhibitor SP600125, ATM inhibitor KU decreases AKT phosphorylation. DM—vehicle control DMSO (0.2%) and SP—SP600125 (20 μM); treatment duration—20 h. Representative Western blots are shown. Total protein stained with Coomassie dye in polyacrylamide gels serve as loading controls.

Article Snippet: Other reagents: 99.5% dimethylsulphoxide DMSO (#7029.1) from Carl Roth, Karlsruhe, Germany; oxaliplatin (5 mg/mL infusion solution) from Fresenius Kabi Oncology Plc., Hampshire, UK; daunorubicin (#251800) and AKT inhibitor VIII (10 μM, #124018) from EMD Millipore/Merck, Billerica, MA, USA; ATM inhibitor KU60019 (5 μM, #S1570) and RAS inhibitor RMC-6236 (1 μM, #E1597) from Selleck Chemicals LLC, Houston, TX, USA; SP600125 (20 μM; #J67272) from Alpha Aesar, Ward Hill, MA, USA; capivasertib AZD5363 (10 μM; #15406) from Cayman Chemical, Ann Arbor, MI, USA.

Techniques: Inhibition, Phospho-proteomics, Control, Western Blot, Staining

Journal: Cell Death & Disease

Article Title: The EHMT2-MBLAC2 axis suppresses ribosomal DNA transcription in response to nucleolar DNA damage

doi: 10.1038/s41419-026-08616-1

Figure Lengend Snippet: A Analysis of nucleolar transcription activity by EU incorporation assay in EHMT2-inactivated HeLa I- Ppo I cells following rDNA DSBs induction. HeLa I- Ppo I cells were pre-treated with ATM inhibitor (ATMi; KU-55933) or EHMT2 inhibitor (EHMT2i; UNC0638) for 1 h prior to rDNA DSBs induction and induced for another 4 h-induction of rDNA DSBs. EU nucleolar intensity was subsequently determined by EU incorporation assay. At least 200 cells exhibiting well-circumscribed nucleoli were quantitatively assessed across minimally three independent experiments. Quantification of relative EU nucleolar intensity is shown in Tukey boxplots. B Fold change of 45S pre-rRNA in HeLa I- Ppo I cells pre-treated with ATM inhibitor (ATMi; KU-55933) or EHMT2 inhibitor (EHMT2i; UNC0638) after I- Ppo I induction was determined by RT-qPCR. Quantification of 45S pre-rRNA fold change was from four independent experiments. C Schematic illustration showing domain structure of EHMT2 protein and its truncated mutants. D Protein expression of the indicated Myc-tagged EHMT2 truncated mutants was measured by Western blotting. E HeLa I- Ppo I cells transduced with EHMT2 gRNA2 were reconstituted with the indicated Myc-tagged EHMT2 truncated mutants. Cells were subjected to EU incorporation assay after I- Ppo I induction. Dashed circle shows the margins of the representative nucleoli. Quantification of relative EU nucleolar intensity was derived from three independent experiments and is shown in Scatter plot. F H3K9me2 nucleolar intensity was determined in EHMT2-deficient HeLa I- Ppo I cells. EHMT2-KO I- Ppo I cells were subjected to immunofluorescence and were labeled with H3K9me2 and 53BP1 after rDNA DSBs induction. Nuclei were counterstained with DAPI. Dashed circle shows the margins of the nucleoli. The white lines in the representative images indicate the lines for quantification. Quantification of relative signal intensities of H3K9me2 in the representative images was shown. The protein levels of H3K9me2 were measured by immunoblotting. Bars represent mean ± SEM; ns not significant; ** P < 0.01; *** P < 0.001; **** P < 0.0001.

Article Snippet: ATM inhibitor (KU-55933, Selleckchem, #S1092, 10 μM); EHMT2 inhibitor (UNC0638, Selleckchem, #S8071, 10 μM); DMSO (Sigma-Aldrich, #D2650); Nucleolar transcription inhibitor (Oxaliplatin, MCE, #HY-17371).

Techniques: Activity Assay, Quantitative RT-PCR, Expressing, Western Blot, Transduction, Derivative Assay, Immunofluorescence, Labeling

Journal: Cell Death & Disease

Article Title: The EHMT2-MBLAC2 axis suppresses ribosomal DNA transcription in response to nucleolar DNA damage

doi: 10.1038/s41419-026-08616-1

Figure Lengend Snippet: A–C HeLa I- Ppo I cells were pre-treated with ATM inhibitor (ATMi; KU-55933) or EHMT2 inhibitor (EHMT2i; UNC0638) for 1 h prior to I- Ppo I induction for 4 h. After fixation, cells were subjected to immunofluorescence with anti-C23 ( A ), anti-Ki-67 ( B ), anti-UBF ( C ) or anti-γH2AX antibodies, respectively. The dashed circles outline margins of the nuclei. Percentages of cells with the indicated protein-containing nucleolar caps were quantified from three experiments. D – F EHMT2-KO HeLa I- Ppo I cells were processed for immunofluorescence as described in ( A – C ). Cells were labeled with anti-C23 ( D ), anti-Ki-67 ( E ), anti-UBF ( F ) or anti-γH2AX antibodies, respectively. Nuclei were counterstained with DAPI. Percentages of cells with the nucleolar caps were quantified from three experiments. Bars represent mean ± SEM; ns not significant; * P < 0.05; ** P < 0.01; *** P < 0.001.

Article Snippet: ATM inhibitor (KU-55933, Selleckchem, #S1092, 10 μM); EHMT2 inhibitor (UNC0638, Selleckchem, #S8071, 10 μM); DMSO (Sigma-Aldrich, #D2650); Nucleolar transcription inhibitor (Oxaliplatin, MCE, #HY-17371).

Techniques: Immunofluorescence, Labeling

Journal: Cell Death & Disease

Article Title: The EHMT2-MBLAC2 axis suppresses ribosomal DNA transcription in response to nucleolar DNA damage

doi: 10.1038/s41419-026-08616-1

Figure Lengend Snippet: A HeLa I- Ppo I cells lenti-virally transduced with control gRNA (CTR gRNA) and EHMT2-targeting gRNAs (EHMT2 KO1 and EHMT2 KO2) were induced with Shield-1 and 4-OHT for 4 h to introduce DSBs into rDNAs. Cells were subjected to neutral comet assay at 6 h and 24 h after recovery from 4 h-rDNA DSBs induction. Relative tail moment from three independent experiments were analyzed and plotted. B The schematic illustration depicts the workflow of micronuclei counting in response to rDNA DSBs. C Representative images depict the micronuclei derived from undamaged and I- Ppo I induced cells treated with ATM or EHMT2 inhibitors. Quantification shows the percentage of cells with micronuclei. Data from three independent experiments were quantified. White arrowheads indicate the locations of micronuclei. D Schematic diagram represents 45S rDNA repeats. I- Ppo I targeted sequence is shown. The labels and the coverage indicated by the arrowheads suggest the primers used in the following quantification of rDNA copy number in I- Ppo I survival cells. E The flow diagram describes the procedure of quantification of rDNA copy number in I- Ppo I survivor cells. F The relative rDNA copy number in EHMT2-deficient GES1 I- Ppo I survival cells was measured and quantified as depicted in ( G ). Data were derived from three independent experiments. G CRISPR–Cas9-mediated EHMT2 knockout (KO) efficiency was validated by Western blotting. H Clonogenic survival of EHMT2 KO HeLa I- Ppo I cells were quantified upon I- Ppo I activation. Briefly, rDNA DSBs in cells were induced with Shield-1 and 4-OHT for 5, 10, or 20 min. Cells were then washed with PBS twice and were cultured to grow for ten days before subjecting to Coomassie blue staining. Bars represent mean ± SEM; ns not significant; * P < 0.05; ** P < 0.01; *** P < 0.001; **** P < 0.0001.

Article Snippet: ATM inhibitor (KU-55933, Selleckchem, #S1092, 10 μM); EHMT2 inhibitor (UNC0638, Selleckchem, #S8071, 10 μM); DMSO (Sigma-Aldrich, #D2650); Nucleolar transcription inhibitor (Oxaliplatin, MCE, #HY-17371).

Techniques: Transduction, Control, Introduce, Neutral Comet Assay, Derivative Assay, Sequencing, CRISPR, Knock-Out, Western Blot, Activation Assay, Cell Culture, Staining

Journal: Nature Communications

Article Title: DNA-PK-mediated phosphorylation of STAT6 establishes a non-canonical type 2 immunity axis to prevent macrophage senescence

doi: 10.1038/s41467-026-69996-8

Figure Lengend Snippet: A Immunoblots of pSTAT6 (pY641) and γH2AX in thioglycolate-elicited peritoneal macrophages (Thio-PM) with Etoposide (Eto) and IL-4 treatment. The right panel shows the relative intensity of pSTAT6 (pY641) ( n = 4 independent experiments). B Immunofluorescence images of staining (pSTAT6 (pY641), red; DAPI, blue) of IL-4-stimulated Thio-PMs treated with Eto. Scale bars 50 μm. Right panel shows the quantification of pSTAT6 (pY641) ( n = 3 biological replicates per group). C Immunoblots of pSTAT6 (pY641) and γH2AX in Eto-treated Thio-PMs with different inhibitors. KU55933, an inhibitor of ATM. Berzosertib, inhibitor of ATR. NU7026, inhibitor of DNA-PK. AZD7762, inhibitor of CHK1/2. The right panel shows the quantification of pSTAT6 (pY641) ( n = 3 independent experiments). D Immunoblots of pSTAT6 (pY641) and γH2AX in Eto-treated Cas9 tg/+ Thio-PMs with indicated sgRNA. The right panel shows the quantification of pSTAT6 (pY641)/tSTAT6 ( n = 3 independent experiments). E Dual luciferase reporter of STAT6 in RAW 264.7 cells treated with Eto and NU7026 ( n = 3 per group). Data are mean ± s.e.m. p-value was calculated by paired two-tailed Student’s t test ( A , D ), unpaired two-tailed Student’s t test ( B ), one-way ANOVA with Dunnett’s correction ( C , E ).

Article Snippet: IL-4 (20 ng/mL, PeproTech, #214-14), DNA-PK inhibitor NU7026 (10 μM, Selleck Chemicals, #S2893), ATM inhibitor KU55933 (10 μM, Selleck Chemicals, #S1092), ATR inhibitor Berzosertib (0.5 μM, Selleck Chemicals, #S7102), CHK1/2 inhibitor AZD7762 (1 μM, Selleck Chemicals, #S1532), STAT6 inhibitor AS1517499 (2 μM, Selleck Chemicals, #S8685), STING inhibitor H151 (1 μM, Selleck Chemicals, #S6652), PTP1B inhibitor (2 μM, Santa Cruz, #sc-222227), PU.1 inhibitor DB2313 (10 nM, MedChem Express, #HY-124629), EPAC inhibitor ESI-09 (10 μM, Selleck Chemicals, #S7499), hIL-4 (20 ng/mL, PeproTech, #200-04), LPS (100 ng/mL, Sigma-Aldrich, #L2630), IFNγ (20 ng/mL, PeproTech, #315-05) were used.

Techniques: Western Blot, Immunofluorescence, Staining, Luciferase, Two Tailed Test

Journal: iScience

Article Title: HP1β recruits RING1A to ubiquitinate histone H2A for BRCA1-mediated resection of double-stand breaks

doi: 10.1016/j.isci.2025.114582

Figure Lengend Snippet: HP1β interacts with RING1A and enhances BRCA1 recruitment at DSB sites (A) Effect of ATM inhibition on clonogenic survival of irradiated cells. Cells were treated with 10 μM ATM inhibitor (KU-55933) for 1h before IR treatment. (B) p -MDC1 foci formation/dissolution in irradiated H1299 cells is not altered by HP1β depletion. (C) FLAG-RING1A co-immunoprecipitated with HA-HP1β. (D) FLAG-RING1A interaction with FLAG-CD HP1β and FLAG-CSD HP1β. (E) RING1A enrichment after DNA damage at Chr1-A and Chr1-B DSB sites as measured by ChIP-qPCR is decreased by HP1β depletion. (F) AlphaFold 3 model of RING1A and HP1β interaction. (G) AlphaFold 3 model of RING1A, CSD HP1β, and CAF1 complex (CAF1A, CAF1B, RBBP4) interaction. HP1-binding motif PxVxL of CAF1A is located near the CSD HP1β and RING1A-binding interface (close-up view). (H) Impact of RING1A depletion on BRCA1 recruitment at Chr1-A and Chr1-C DSB sites before and after I-Sce1 transfection. (I) Effect of RING1A depletion on IR-induced BRCA1 foci with and without HP1β. (J) Decreased single-strand DNA formation at DSBs in RING1A or HP1β-depleted cells as measured by the ER-AsiSI assay. Experiments were done three times and standard deviation was calculated. ∗ p < 0.05; ∗∗ p < 0.01; ∗∗∗ p < 0.001; ∗∗∗∗ p < 0.0001.

Article Snippet: ATM inhibitor (KU-55933) ATM inhibitor (KU-55933) , MCE Millipore Sigma , Cat# HY-12016 Cat # 1185000.

Techniques: Inhibition, Irradiation, Dissolution, Immunoprecipitation, ChIP-qPCR, Binding Assay, Transfection, Standard Deviation

Journal: iScience

Article Title: HP1β recruits RING1A to ubiquitinate histone H2A for BRCA1-mediated resection of double-stand breaks

doi: 10.1016/j.isci.2025.114582

Figure Lengend Snippet: HP1β modulates H2AK119-ub levels at DSB sites to promote S-phase-specific IR-induced chromosome damage repair (A and B) HP1β depletion decreases H2AK119Ub1 at 1 h and 2-h post IR recovery. Control and HP1β-depleted cells were irradiated by radiation dose of 4Gy. (A) Anti-Ub antibody was used for immunoprecipitation followed by western blot analysis with H2AK119Ub antibody. (B) Quantification of H2AK119Ub1 was performed following normalization with H2A Input western blots. (C) Effect of HP1β depletion on -ub levels at the Chr1-A and Chr1-B sites before and after DSB induction as determined by ChIP-qPCR. (D) Impact of BRCA1 depletion on RING1A enrichment at the DSB. Depletion of BRCA1 has no impact on the enrichment of RING1A at the DSB. (E) Depletion of RING1A but not BRCA1 results in the decreased enrichment of H2AK119-ub at the DSB. (F) H2A-ub reversal of radiosensitivity in HP1β-depleted cells is independent of ATM. Cells with and without HP1β depletion were treated with ATM inhibitor (KU 55933) then treated with increasing IR doses. Effect of H2A-ub expression on cell survival was determined by clonogenic survival. (G) Exogenous H2A-ub partially restores HR in HP1β-depleted cells as determined by the DR-GFP repair assay. (H) Ectopic expression of H2A-ub or FLAG-CSD HP1β reduces S-phase-specific IR-induced residual chromosome damage in HP1β-depleted cells. Three independent experiments were conducted and an SD value between experiments was determined. ∗ p < 0.05; ∗∗ p < 0.01; ∗∗∗ p < 0.001; ∗∗∗∗ p < 0.0001.

Article Snippet: ATM inhibitor (KU-55933) ATM inhibitor (KU-55933) , MCE Millipore Sigma , Cat# HY-12016 Cat # 1185000.

Techniques: Control, Irradiation, Immunoprecipitation, Western Blot, ChIP-qPCR, Expressing