Tags: Protein.
In molecular biology a saposin protein domain is a region of the saposin protein that has a certain conserved sequence or structure that defines a domain. Saposins are small lysosomal proteins that serve as activators of various lysosomal lipid-degrading enzymes. They probably act by isolating the lipid substrate from the membrane surroundings thus making it more accessible to the soluble degradative enzymes.
