3'-5' DNA helicase that may play a role in the repair of DNA. ATP + H2O = ADP + H(+) + phosphate Mostly expressed in shoots, flowers, siliques and seeds, and, to a lower extent, in roots, seedlings, leaves, shoots, shoot apical mersitem, and inflorescences. By cold. Repressed by drought. Belongs to the helicase family. RecQ subfamily.