Figure 6.

Human Prosaposin. The cDNA of human prosaposin codes for a sequence of 524 (or 527) amino acids including a signal peptide of 16 amino acids.^92,94) The precursor is proteolytically processed in the endolysosomal compartment to 4 domains, saposin A, B, C and D.¹⁰²⁾ Cystein residues are marked by vertical bars, N-glycosylation sites by arrow heads. Disease causing mutations affecting human Sap-A,²⁵⁵⁾ Sap-B,^64,65) Sap-C²⁵⁶⁾ and prosaposin^67,96,257) have been described. Murine models of prosaposin deficiency⁷⁷⁾ and deficiencies of individual saposins have been investigated: Sap-A,^78,80,258) Sap-B,⁷⁶⁾ Sap-C⁷⁹⁾ and Sap-D.^80,105,259)