Spy1, a unique cell cycle regulator, alters viability in ALS motor neurons and cell lines in response to mutant SOD1-induced DNA damage.

•Spy1, a unique cell cycle regulator, was decreased in ALS motor neurons.•DNA damage response was activated in SOD1G93A-transfected cells.•Decreased Spy1 expression activated the DNA damage response in SOD1G93A-transfected cells.•Increased Spy1 expression inhibited the DNA damage response in SOD1G93A-transfected cells.•Spy1 played a protective role in ALS motor neurons.