| First Author | Ham D | Year | 2003 |
| Journal | Cell Biol Int | Volume | 27 |
| Issue | 8 | Pages | 675-87 |
| PubMed ID | 12867159 | Mgi Jnum | J:84480 |
| Mgi Id | MGI:2667786 | Doi | 10.1016/s1065-6995(03)00124-0 |
| Citation | Ham D (2003) Structural requirements for lysosomal targeting of the prosaposin precursor protein. Cell Biol Int 27(8):675-87 |
| abstractText | Although the Man-6-P-independent lysosomal sorting of prosaposin, a precursor of four saposins (A, B, C, and D) is not understood, a protein/lipid interaction is considered. Immunocytochemical analysis revealed that each single saposin linked to the C-terminus of prosaposin and to secretory albumin, drives the chimeric protein to lysosomes in COS-7 cells. Quantitative image analysis demonstrated that saposins are targeted with different efficiency (P<0.05) and in a less smooth manner than the precursor. Despite a very close homology, the charge distribution at the surface of 3D comparative models between saposins appeared different. Western blotting monitored prosaposin in cells also as a di- or trimeric form, whereas the chimeric saposins as monomeric. This implies that each amphipathic saposin-like motif may be a part of the overall structural requirements for binding of the precursor to the membrane lipids of transport vesicle. The crystal structure of saposin B demonstrating two dimeric units for lipid binding supports current findings. |
