DNA helicase that plays a role in DNA damage repair and genome stability (PubMed:15886194, PubMed:35025765, PubMed:7527136, PubMed:7961977, PubMed:8056767). Exhibits a Mg(2+)- and ATP-dependent DNA-helicase activity that unwinds single- and double-stranded DNA in a 3'-5' direction (PubMed:19151156, PubMed:35025765, PubMed:7527136, PubMed:8056767). Full-length protein unwinds forked DNA substrates, resolves Holliday junctions, and has DNA strand annealing activity (PubMed:19151156, PubMed:25831490). Plays a role in restoring regressed replication forks (PubMed:35025765). Required to restart stalled replication forks induced by abortive topoisomerase 1 and 2 lesions (PubMed:35025765). Does not unwind G-quadruplex DNA (PubMed:18426915). May play a role in the repair of DNA that is damaged by ultraviolet light or other mutagens (PubMed:15886194, PubMed:7961977). {ECO:0000269|PubMed:15886194, ECO:0000269|PubMed:18426915, ECO:0000269|PubMed:19151156, ECO:0000269|PubMed:25831490, ECO:0000269|PubMed:35025765, ECO:0000269|PubMed:7527136, ECO:0000269|PubMed:7961977, ECO:0000269|PubMed:8056767}. This is the function of RECQL (RecQ like helicase, Ensembl gene identifier ENSG00000004700).