Exhibits ATP-dependent 3' to 5' DNA helicase activity and has a role in telomerase-independent telomere maintenance. Represses ade6 at an ectopic site. ATP + H2O = ADP + H(+) + phosphate Repressed during various growth conditions, including nitrogen starvation, and by heterochromatin. Repression is strongly dependent on cul4, raf2 and raf1. Derepressed by histone deacetylase inhibitor TSA. Belongs to the helicase family. RecQ subfamily. Extended N-terminus.