18 September 1998
Vol 281, Issue 5384

About The Cover

Cover image expansion

COVER In Lou Gehrig's disease [or amyotrophic lateral sclerosis (ALS)] the death of motor neurons causes muscles to atrophy. Many instances of ALS are caused by mutations in the enzyme superoxide dismutase (SOD1). Studies of mice expressing mutant SOD1 revealed that toxicity is independent of wild-type enzyme activity, but a common feature of ALS is intracellular aggregates of mutant SOD1 in motor neurons (brown staining) (image width ~50 micrometers). See page 1851. [Photo: L. I. Bruijn]