Essential factor involved in transcription-coupled nucleotide excision repair (TC-NER), a process during which RNA polymerase II- blocking lesions are rapidly removed from the transcribed strand of active genes (PubMed:16246722, PubMed:20541997, PubMed:22483866, PubMed:26620705, PubMed:32355176, PubMed:34526721, PubMed:38316879, PubMed:38600235, PubMed:38600236). Plays a central role in the initiation of the TC-NER process: specifically recognizes and binds RNA polymerase II stalled at a lesion, and mediates recruitment of ERCC8/CSA, initiating DNA damage excision by TFIIH recruitment (PubMed:32355176, PubMed:34526721, PubMed:38600235, PubMed:38600236). Upon DNA-binding, it locally modifies DNA conformation by wrapping the DNA around itself, thereby modifying the interface between stalled RNA polymerase II and DNA (PubMed:15548521). Acts as a chromatin remodeler at DSBs; DNA-dependent ATPase-dependent activity is essential for this function (PubMed:16246722, PubMed:9565609). Plays an important role in regulating the choice of the DNA double-strand breaks (DSBs) repair pathway and G2/M checkpoint activation; DNA-dependent ATPase activity is essential for this function (PubMed:25820262). Regulates the DNA repair pathway choice by inhibiting non-homologous end joining (NHEJ), thereby promoting the homologous recombination (HR)-mediated repair of DSBs during the S/G2 phases of the cell cycle (PubMed:25820262). Mediates the activation of the ATM- and CHEK2-dependent DNA damage responses thus preventing premature entry of cells into mitosis following the induction of DNA DSBs (PubMed:25820262). Remodels chromatin by evicting histones from chromatin flanking DSBs, limiting RIF1 accumulation at DSBs thereby promoting BRCA1-mediated HR (PubMed:29203878). Required for stable recruitment of ELOA and CUL5 to DNA damage sites (PubMed:28292928). Also involved in UV-induced translocation of ERCC8 to the nuclear matrix (PubMed:26620705). Essential for neuronal differentiation and neuritogenesis; regulates transcription and chromatin remodeling activities required during neurogenesis (PubMed:24874740). {ECO:0000269|PubMed:15548521, ECO:0000269|PubMed:16246722, ECO:0000269|PubMed:20541997, ECO:0000269|PubMed:22483866, ECO:0000269|PubMed:24874740, ECO:0000269|PubMed:25820262, ECO:0000269|PubMed:26620705, ECO:0000269|PubMed:28292928, ECO:0000269|PubMed:29203878, ECO:0000269|PubMed:32355176, ECO:0000269|PubMed:34526721, ECO:0000269|PubMed:38316879, ECO:0000269|PubMed:38600235, ECO:0000269|PubMed:38600236, ECO:0000269|PubMed:9565609}. Involved in repair of DNA damage following UV irradiation, acting either in the absence of ERCC6 or synergistically with ERCC6. Involved in the regulation of gene expression. In the absence of ERCC6, induces the expression of genes characteristic of interferon-like antiviral responses. This response is almost completely suppressed in the presence of ERCC6. In the presence of ERCC6, regulates the expression of genes involved in metabolism regulation, including IGFBP5 and IGFBP7. In vitro binds to PGBD3-related transposable elements, called MER85s; these non-autonomous 140 bp elements are characterized by the presence of PGBD3 terminal inverted repeats and the absence of internal transposase ORF. . This is the function of ERCC6 (ERCC excision repair 6, chromatin remodeling factor, ENSG00000225830).