Table 1.

Role of post-translational modifications in DPC repair.

PTM	Type of DPC	Linkage Determined	Connection to Repair	References
Ubiquitin	TOP1/2	K11, K48, K63	Promotes transcription-dependent, proteasome-dependent repair Recruits TDP2	[14,90,92,169]
	DNMT1	K48	Recruits proteasome during replication-dependent repair	[85]
	HpaII		Triggers proteasomal recruitment in the absence of replication Promotes SUMO-independent repair in the absence of replication	[85,94]
	Formaldehyde induced		Triggers SPRTN-dependent, proteasome-independent repair during S phase progression	[95,102]
	MGMT		Recruits proteasome	[82]
	OGG1	K48, K63	Triggers replication-independent, transcription-independent repair K48 promotes proteasome-dependent repair by NER K63 promotes proteasome-independent repair by HR	[93]
	HMCES		Triggers TLS across DPCs on single-stranded DNA	[170]
	EOS		Triggers unfolding by p97 to facilitate proteolysis by SPRTN	[112]
SUMO	TOP1/2	K7, K11	Triggers ubiquitination and proteasomal degradation SUMO2/3 triggers TDP2 recruitment	[14,91,135,136,169]
	DNMT1		Triggers ubiquitination to recruit proteasome during replication-dependent repair Promotes HR SUMO2/3 triggers ubiquitination via RNF4, and triggers RNF4-independent repair	[84,85,102]
	HpaII		Triggers SPRTN recruitment during replication-independent repair	[94]
	Formaldehyde induced		Recruits ACRC protease SUMO1 promotes SPRTN-dependent, proteasome-independent repair, as well as SPRTN-independent repair SUMO2/3 promotes SPRTN-dependent, proteasome-independent repair	[95,102]
PAR	TOP1		Triggers deubiquitination to block proteasomal processing Triggers TDP1 recruitment	[83]