Molecular chaperone for LDL receptor-related proteins that may regulate their ligand binding activity along the secretory pathway.
Subcellular locations: Rough endoplasmic reticulum lumen, Endoplasmic reticulum-Golgi intermediate compartment lumen, Golgi apparatus, Cis-Golgi network, Golgi apparatus lumen, Endosome lumen, Cell surface
May be associated with receptors at the cell surface.