Worms delay in deep sleep

Worms deprived of all oxygen can pause, take a deep breath, and enter a suspended animation from which they can emerge unscathed several days later. Now, Mark Roth (Fred Hutchinson Cancer Research Center, Seattle, WA) and colleagues show that these worms use the spindle checkpoint to prevent passage through mitosis during anoxia. This arrest is essential for the worms' survival.

The Seattle group knew that the anoxic response was not just an exaggerated version of the hypoxic (low oxygen) response, because hypoxia-inducible factor 1 (HIF-1) was not needed for survival in anoxia. They conducted an RNAi screen, and found that two genes are uniquely required for survival in anoxia: san-1 (suspended animation 1, which is similar to the spindle checkpoint gene mad3) and mdf-2 (similar to mad2)....