Enables lipase binding activity. Predicted to be involved in several processes, including amyloid-beta clearance by transcytosis; negative regulation of amyloid-beta clearance; and negative regulation of very-low-density lipoprotein particle clearance. Located in rough endoplasmic reticulum lumen and vesicle. Used to study membranous glomerulonephritis. Biomarker of membranous glomerulonephritis. Human ortholog(s) of this gene implicated in Alzheimer's disease; dementia; myocardial infarction; and myopia. Orthologous to human LRPAP1 (LDL receptor related protein associated protein 1). [provided by Alliance of Genome Resources, Apr 2022]