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Histone deacetylase 4 interacts with 53BP1 to mediate the DNA damage response.

Kao GD, McKenna WG, Guenther MG, Muschel RJ, Lazar MA, Yen TJ - J. Cell Biol. (2003)

Bottom Line: Anumber of proteins are recruited to nuclear foci upon exposure to double-strand DNA damage, including 53BP1 and Rad51, but the precise role of these DNA damage-induced foci remain unclear.Silencing of HDAC4 via RNA interference surprisingly also decreased levels of 53BP1 protein, abrogated the DNA damage-induced G2 delay, and radiosensitized HeLa cells.Our combined results suggest that HDAC4 is a critical component of the DNA damage response pathway that acts through 53BP1 and perhaps contributes in maintaining the G2 cell cycle checkpoint.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. kao@xrt.upenn.edu

ABSTRACT
Anumber of proteins are recruited to nuclear foci upon exposure to double-strand DNA damage, including 53BP1 and Rad51, but the precise role of these DNA damage-induced foci remain unclear. Here we show in a variety of human cell lines that histone deacetylase (HDAC) 4 is recruited to foci with kinetics similar to, and colocalizes with, 53BP1 after exposure to agents causing double-stranded DNA breaks. HDAC4 foci gradually disappeared in repair-proficient cells but persisted in repair-deficient cell lines or cells irradiated with a lethal dose, suggesting that resolution of HDAC4 foci is linked to repair. Silencing of HDAC4 via RNA interference surprisingly also decreased levels of 53BP1 protein, abrogated the DNA damage-induced G2 delay, and radiosensitized HeLa cells. Our combined results suggest that HDAC4 is a critical component of the DNA damage response pathway that acts through 53BP1 and perhaps contributes in maintaining the G2 cell cycle checkpoint.

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Recruitment of HDAC4 to nuclear foci after double-strand DNA damage. HeLa cells that were (A) unirradiated, (B) irradiated with 2 Gy, (C) irradiated and probed with secondary antibody only, (D) irradiated and probed with primary antibody (anti-HDAC4) immunodepleted with the immunizing antigen. (E) HeLa cells exposed to UV (50 J/m2) and (F) 20 μM etoposide were fixed after 1 h and stained with HDAC4 antibodies. (G and H) DAPI stain of cells in E and F, respectively, were merged with HDAC4. Cells irradiated with 2 Gy were stained for (I) HDAC2 and (J) HDAC6. All staining of irradiated cells was performed 1 h after IR. Bar, 5 μm.
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fig1: Recruitment of HDAC4 to nuclear foci after double-strand DNA damage. HeLa cells that were (A) unirradiated, (B) irradiated with 2 Gy, (C) irradiated and probed with secondary antibody only, (D) irradiated and probed with primary antibody (anti-HDAC4) immunodepleted with the immunizing antigen. (E) HeLa cells exposed to UV (50 J/m2) and (F) 20 μM etoposide were fixed after 1 h and stained with HDAC4 antibodies. (G and H) DAPI stain of cells in E and F, respectively, were merged with HDAC4. Cells irradiated with 2 Gy were stained for (I) HDAC2 and (J) HDAC6. All staining of irradiated cells was performed 1 h after IR. Bar, 5 μm.

Mentions: To investigate a potential role of HDACs in the DNA damage response in human cells, we studied the response of HDAC2, 4, and 6 to DNA damage. HeLa cells exposed to γ-irradiation (IR) or etoposide exhibited distinct foci of HDAC4 in their nucleus (Fig. 1, B and D), whereas unirradiated (Fig. 1 A) or UV exposure did not have this effect (Fig. 1 E). In contrast, DNA damage did not induce foci formation by HDAC2 (Fig. 1 I) or HDAC6 (Fig. 1 J) or noticeably alter their intracellular localization. We observed IR-induced HDAC4 foci in both transformed and untransformed cell lines, including the breast cancer cell lines MCF7, PA1, SKBR, and MO59J and K (both of gliomatous origin), the sarcoma cell lines U20S, HT29, and HT1080 (latter two are colon cancer lines), and Wi38 and WSC (normal human fibroblasts) (unpublished data). Thus, foci formation by HDAC4 in response to DNA damage appears to be a general cellular response that does not appear to be dependent on p53.


Histone deacetylase 4 interacts with 53BP1 to mediate the DNA damage response.

Kao GD, McKenna WG, Guenther MG, Muschel RJ, Lazar MA, Yen TJ - J. Cell Biol. (2003)

Recruitment of HDAC4 to nuclear foci after double-strand DNA damage. HeLa cells that were (A) unirradiated, (B) irradiated with 2 Gy, (C) irradiated and probed with secondary antibody only, (D) irradiated and probed with primary antibody (anti-HDAC4) immunodepleted with the immunizing antigen. (E) HeLa cells exposed to UV (50 J/m2) and (F) 20 μM etoposide were fixed after 1 h and stained with HDAC4 antibodies. (G and H) DAPI stain of cells in E and F, respectively, were merged with HDAC4. Cells irradiated with 2 Gy were stained for (I) HDAC2 and (J) HDAC6. All staining of irradiated cells was performed 1 h after IR. Bar, 5 μm.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2172769&req=5

fig1: Recruitment of HDAC4 to nuclear foci after double-strand DNA damage. HeLa cells that were (A) unirradiated, (B) irradiated with 2 Gy, (C) irradiated and probed with secondary antibody only, (D) irradiated and probed with primary antibody (anti-HDAC4) immunodepleted with the immunizing antigen. (E) HeLa cells exposed to UV (50 J/m2) and (F) 20 μM etoposide were fixed after 1 h and stained with HDAC4 antibodies. (G and H) DAPI stain of cells in E and F, respectively, were merged with HDAC4. Cells irradiated with 2 Gy were stained for (I) HDAC2 and (J) HDAC6. All staining of irradiated cells was performed 1 h after IR. Bar, 5 μm.
Mentions: To investigate a potential role of HDACs in the DNA damage response in human cells, we studied the response of HDAC2, 4, and 6 to DNA damage. HeLa cells exposed to γ-irradiation (IR) or etoposide exhibited distinct foci of HDAC4 in their nucleus (Fig. 1, B and D), whereas unirradiated (Fig. 1 A) or UV exposure did not have this effect (Fig. 1 E). In contrast, DNA damage did not induce foci formation by HDAC2 (Fig. 1 I) or HDAC6 (Fig. 1 J) or noticeably alter their intracellular localization. We observed IR-induced HDAC4 foci in both transformed and untransformed cell lines, including the breast cancer cell lines MCF7, PA1, SKBR, and MO59J and K (both of gliomatous origin), the sarcoma cell lines U20S, HT29, and HT1080 (latter two are colon cancer lines), and Wi38 and WSC (normal human fibroblasts) (unpublished data). Thus, foci formation by HDAC4 in response to DNA damage appears to be a general cellular response that does not appear to be dependent on p53.

Bottom Line: Anumber of proteins are recruited to nuclear foci upon exposure to double-strand DNA damage, including 53BP1 and Rad51, but the precise role of these DNA damage-induced foci remain unclear.Silencing of HDAC4 via RNA interference surprisingly also decreased levels of 53BP1 protein, abrogated the DNA damage-induced G2 delay, and radiosensitized HeLa cells.Our combined results suggest that HDAC4 is a critical component of the DNA damage response pathway that acts through 53BP1 and perhaps contributes in maintaining the G2 cell cycle checkpoint.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. kao@xrt.upenn.edu

ABSTRACT
Anumber of proteins are recruited to nuclear foci upon exposure to double-strand DNA damage, including 53BP1 and Rad51, but the precise role of these DNA damage-induced foci remain unclear. Here we show in a variety of human cell lines that histone deacetylase (HDAC) 4 is recruited to foci with kinetics similar to, and colocalizes with, 53BP1 after exposure to agents causing double-stranded DNA breaks. HDAC4 foci gradually disappeared in repair-proficient cells but persisted in repair-deficient cell lines or cells irradiated with a lethal dose, suggesting that resolution of HDAC4 foci is linked to repair. Silencing of HDAC4 via RNA interference surprisingly also decreased levels of 53BP1 protein, abrogated the DNA damage-induced G2 delay, and radiosensitized HeLa cells. Our combined results suggest that HDAC4 is a critical component of the DNA damage response pathway that acts through 53BP1 and perhaps contributes in maintaining the G2 cell cycle checkpoint.

Show MeSH
Related in: MedlinePlus