The function of PRAP1 (proline rich acidic protein 1, ENSG00000165828) is as follows. Lipid-binding protein which promotes lipid absorption by facilitating MTTP-mediated lipid transfer (mainly triglycerides and phospholipids) and MTTP-mediated apoB lipoprotein assembly and secretion (By similarity). Protects the gastrointestinal epithelium from irradiation-induced apoptosis (By similarity). May play an important role in maintaining normal growth homeostasis in epithelial cells (PubMed:14583459). Involved in p53/TP53-dependent cell survival after DNA damage (PubMed:23235459). May down-regulate the expression of MAD1L1 and exert a suppressive role in mitotic spindle assembly checkpoint in hepatocellular carcinomas (PubMed:24374861). {ECO:0000250|UniProtKB:Q80XD8, ECO:0000269|PubMed:14583459, ECO:0000269|PubMed:23235459, ECO:0000269|PubMed:24374861}.