Effects of SWI/SNF complex on DNA damage repair in heterochromatin of embryonic fibroblast cells
Effects of SWI/SNF complex on DNA damage repair in heterochromatin of embryonic fibroblast cells
复制标题
DOI：
10.1016/j.radmp.2023.10.006
复制
发表时间：
2023-10
影响因子：
--
通讯作者：
Hong Zhang;Yinyin Shu;Mintao Ji
中科院分区：
文献类型：
--
作者：
Hong Zhang;Yinyin Shu;Mintao Ji
目的研究SWI/SNF复合物对X射线照射后异染色质DNA损伤修复的影响，探讨其可能的作用机制。转染后24小时，用0.5和1戈伊X射线照射细胞。照射后20、60和240 min，进行γ H2 AX测定以评价总染色质或异染色质的辐射反应。用彗星试验检测雅普/TAZ在4戈伊X射线照射后对细胞DNA的损伤作用。以50 nmol/L siRNA分别作用于NIH 3 T3细胞，观察BRM/BRG 1和雅普/TAZ在异染色质DNA损伤修复中的作用在1戈伊照射后60 min，BRM、ARID 1A和BRG 1基因敲低增加了总染色质和异染色质中的γ H2 AX SNF 5基因敲低组γ H2 AX表达在照射后1戈伊20 min显著降低（P < 0.05）。在MRC 5中，BRM和BRG 1基因敲低使γ H2 AX在照射后60 min的总染色质和异染色质中的表达增加（P < 0.05）。不一致的是，ARID 1A敲低并不影响它，SNF 5敲低在照射后1戈伊60 min增加异染色质γ H2 AX（P < 0.05）。此外，雅普/TAZ基因敲减后，NIH 3 T3和MRC 5细胞异染色质γ H2 AX表达量显著降低（P < 0.05）。在彗星实验中，雅普/TAZ敲低组在4戈伊照射后60 min的尾矩明显降低（P < 0.05）。BRM/BRG 1联合雅普/TAZ基因敲除在0.5戈伊照射后60 min时，与单一BRM/BRG 1基因敲除相比，异染色质γ H2 AX表达显著降低（P < 0.05）。BRM/BRG 1基因敲低通过雅普/TAZ促进γ H2 AX在异染色质中的积累。该研究为DNA损伤修复提供了新的方向，并揭示了SWI/SNF复合物在异染色质DNA损伤修复中的作用。
ObjectiveTo investigate the impact of SWI/SNF complex on heterochromatin DNA damage repair after exposure to X-ray irradiation, in order to explore the underlying mechanism.MethodsNIH3T3 and MRC5 cells were treated with 50 nmol/L siRNA targeting SWI/SNF complex subunits (BRM, ARID1A, BRG1 and SNF5), and YAP/TAZ. At 24 h after transfection, the cells were irradiated with 0.5 and 1 Gy of X-rays. At 20, 60 and 240 min post-irradiation, γH2AX assay was performed to evaluate the radiation response in total or heterochromatin. Comet assay was used to determine the role of YAP/TAZ in DNA damage when the cells were irradiated with 4 Gy of X-rays. NIH3T3 were treated with 50 nmol/L siRNA targeting BRM/BRG1 and YAP/TAZ to determine their relationship on heterochromatin DNA damage repair.ResultsIn NIH3T3, SWI/SNF complex subunits (BRM, ARID1A and BRG1) knock-down increased γH2AX in total and heterochromatin at 1 Gy 60 min post-irradiation (P< 0.05), while SNF5 knock-down decreased heterochromatin γH2AX at 1 Gy 20 min post-irradiation (P< 0.05). In MRC5, BRM and BRG1 knock-down increased γH2AX in total and heterochromatin at 1 Gy 60 min post-irradiation (P< 0.05). Inconsistently, ARID1A knock-down did not affect it, and SNF5 knock-down increased heterochromatin γH2AX at 1 Gy 60 min post-irradiation (P< 0.05). Moreover, YAP/TAZ knock-down decreased heterochromatin γH2AX in NIH3T3 and MRC5 (P< 0.05). Meanwhile, YAP/TAZ knock-down decreased Tail Moment in comet assay at 4 Gy 60 min post-irradiation (P< 0.05). BRM/BRG1 combining with YAP/TAZ knock-down significantly decreased heterochromatin γH2AX compared with single BRM/BRG1 knock-down at 0.5 Gy 60 min post-irradiation (P< 0.05).ConclusionsThe SWI/SNF complex subunits exhibited varying effects on DNA damage repair. BRM/BRG1 knock-down promoted γH2AX accumulation in heterochromatin through YAP/TAZ. This study provides a novel direction for DNA damage repair and sheds light on the role of SWI/SNF complex in response to DNA damage repair in heterochromatin.