Lysosomes require the presence of many specialized proteins to facilitate their 
roles in cellular maintenance. One such protein that has proven to be an 
important player in the lysosomal field is lysosomal integral membrane protein-2 
(LIMP-2), encoded by the gene SCARB2. LIMP-2 is required for the normal 
biogenesis and maintenance of lysosomes and endosomes and has been identified as 
the specific receptor for glucocerebrosidase, the enzyme deficient in Gaucher 
disease. Research into LIMP-2 and the SCARB2 gene indicate that it may be a 
factor contributing to the clinical heterogeneity seen among patients with 
Gaucher disease. Mutations in SCARB2 have also been identified as the cause of 
action myoclonus renal failure (AMRF), and in some cases progressive myoclonic 
epilepsy. A total of 14 disease-causing SCARB2 mutations have been identified to 
date. The role of LIMP-2 in human pathology has expanded with its identification 
as a component of the intercalated disk in cardiac muscle and as a receptor for 
specific enteroviruses, two unanticipated findings that reaffirm the myriad 
roles of lysosomal proteins. Studies into the full impact of LIMP-2 deficiency 
and the LIMP2/glucocerebrosidase molecular pathway will lead to a better 
understanding of disease pathogenesis in Gaucher disease and AMRF, and to new 
insights into lysosomal processing, trafficking and function.