Heat shock protein 70 (Hsp70) is a molecular chaperone which, by inhibiting lysosomal membrane permeabilization, promotes the survival of stressed cells. Hsp70 is now shown to stabilize lysosomes by binding to an anionic phospholipid, BMP, resulting in stimulation of acid sphingomyelinase (ASM) activity. Notably, the decreased ASM activity and lysosomal stability seen in patients with Niemann–Pick disease can be corrected by treatment with recombinant Hsp70.
- Thomas Kirkegaard
- Anke G. Roth
- Marja Jäättelä
