Table 1. Core histone dynamics in response to DNA damage (as known in mammalian cells, unless stated otherwise).

53BP1: Tumor suppressor p53-binding protein 1; APLF: Aprataxin-PNK-like factor; ASF1: Anti-Silencing Factor 1; ATM: Ataxia telangiectasia mutated; ATR: Ataxia telangiectasia and Rad3-related protein; BRCA1: breast cancer early onset 1; CHRAC14: Chromatin Accessibility Complex 14; DNA-PKcs: DNA-dependent protein kinase catalytic subunit; HAT1: Histone AcetylTransferase 1; IR: Ionizing Radiation; MEF: Mouse Embryonic Fibroblasts; PARP: Poly(ADP-Ribose) Polymerase; UBC13: Ubiquitin-conjugating protein 13; XPC: Xeroderma Pigmentosum, complementation group C; XRCC4 : X-ray cross-complementing group 4.

Core histones	Dynamics at damaged sites	Regulatory factors	Impact on the DNA damage response	References
H2A/H2B (outer core histones)
H2A-H2B	Loss of H2A-H2B density around DSBs	Nucleolin chaperone	Nucleolin promotes XRCC4 recruitment to DSBs	[19,20]
	Loss of H2A density at UVC damage sites	DDB2, ATP, PARP	DDB2, ATP and PARP promote UVC damage recognition by XPC	[22]
	Enhanced turnover at sites of UVC irradiation	FACT chaperone (SPT16 subunit)	FACT promotes transcription restart after UVC damage	[27]
	De novo incorporation of H2A at UVC damaged sites	FACT chaperone?	?	[27]
H2A.X	Phosphorylated at S139 in the vicinity of DNA damage	ATM, ATR, DNA-PKcs kinases	Docking site for the recruitment of DNA repair and checkpoint proteins	[55]; reviewed in [6]
	Nucleosomal dissociation increased upon H2A.X S139 phosphorylation	FACT chaperone TIP60 acetyltransferase & p400 remodeler (Drosophila)	FACT promotes DSB repair by HR	[25,26,56]
	Increased mobility in damaged chromatin (sites of UVA laser micro-irradiation)	TIP60 acetyltransferase & UBC13 ubiquitin-conjugating enzyme	TIP60 promotes RAD51 recruitment to DSBs	[23,57]
	Increased extractability from bleomycin-damaged chromatin	TIP60 acetyltransferase & p400 remodeler	p400 promotes ubiquitin-dependent DSB signaling and DSB repair by HR	[17,21]
H2A.Z	Accumulation at DSBs at late time points after damage (restricted to silent chromatin?)	p400 remodeler	Role in DSB repair by HR and NHEJ by controlling resection? (conflicting results)	[28,29]
	H2A.Z.2 (not H2A.Z.1) shows increased mobility at sites of UVA laser micro-irradiation	?	H2A.Z.2 promotes DSB repair by HR & survival to IR? (conflicting results)	[24,29]
macroH2A	mH2A1.1 macrodomain is recruited to sites of UVA laser micro-irradiation through PAR binding	PARP1 & APLF chaperone	Local chromatin compaction?	[32,33]
	mH2A1.1 associates with PARylated chromatin at DSBs (not incorporated into nucleosomes)	PARP1	Promotes 53BP1 accumulation, restrains NHEJ?	[30]
	mH2A1.2 accumulates at DSBs after transient depletion	ATM	Promotes chromatin compaction, BRCA1 recruitment and HR	[31]
H2A.Bbd	Accumulates at UVA laser-induced repair foci upon ectopic expression in MEFs	?	?	[34]
H3/H4 (inner core histones)
H3-H4	Loss of H3-H4 density around DSBs (not in G1)	p400 remodeler, ASF1 chaperone	p400 promotes RAD51 recruitment and DSB repair by HR	[20,21]
	Loss of H4 density at UVC damage sites	DDB2, ATP, PARP	DDB2, ATP and PARP promote UVC damage recognition by XPC	[22]
	No enhanced turnover at sites of UVC irradiation			[27]
H3.1	De novo incorporation at UVC damage sites and at sites of UVA laser damage	CAF-1 chaperone	Coupled to repair synthesis but not required for UVC damage signaling and repair	[39]
H3.2	?	CAF-1 chaperone	?	[40]
H3.3	Accumulation at DSBs	HIRA chaperone & HAT1 (H4 acetyltransferase)	HAT1 facilitates RAD51 recruitment and DSB repair by HR	[35]35]
	De novo incorporation at UVC damage sites	HIRA chaperone	HIRA promotes transcription restart after UVC damage H3.3 promotes replication fork progression after UVC damage (Chicken cells)	[42] [44]
CENPA	Accumulation at DSBs? (conflicting results)			[36,37]
	Mistargeted to DSBs in the absence of CHRAC14 (Drosophila)	CHRAC14 (remodeling complex subunit)	Ectopic kinetochore formation & genome instability	[38]
	Not incorporated de novo at UVC damage sites			[42]