Skip to main content
. Author manuscript; available in PMC: 2013 Dec 31.
Published in final edited form as: Cancer Lett. 2012 Feb 19;327(1-2):61–72. doi: 10.1016/j.canlet.2012.02.001

Table 3.

The major steps and protein participants in global genome and transcription-coupled NER. Only the recognition step differs between these two sub-pathways of NER.

NER STEP PROTEIN BIOCHEMICAL ACTIVITY SUBSTRATE
RECOGNITION GLOBAL GENOME XPC/RAD23B DNA Binding/TFIIH recruitment DNA helix distortion
DDB1/DDB2 (XPE) DNA Binding UV-damaged DNA
XPA DNA Binding XPC-TFIIH bound DNA
TRANSCRIPTION COUPLED CSA Unknown/Part of ubiquitin ligase complex Stalled RNA Pol
CSB DNA-dependent ATPase Stalled RNA Pol
DNA UNWINDING (TFIIH Multisubunit Complex*) XPB (ERCC3) 3′ to 5′ DNA helicase/ATPase
XPD (ERCC2) 5′ to 3′ DNA helicase/ATPase
INCISION XPG (ERCC5) 3′-Incision 5′-Flap, Bubble
ERCC1/XPF (ERCC4) 5′-Incision complex (catalyzed by XPF) 3′-Flap, Bubble
POLYMERIZATION POLδ (POLε) PCNA-dependent replicative polymerase(s) DNA gap (~25–30 nt)
LIGATION LIG1 Ligase DNA nick
XRCC1/LIG3α Ligase complex DNA nick
*

Of the multiple subunits that comprise the TFIIH transcription complex, only XPB and XPD are listed here. RPA (not listed) participates in NER by binding and protecting the single-stranded DNA regions generated upon duplex unwinding.

HHS Vulnerability Disclosure