May function as an adapter protein. Required for efficient phagocytosis of apoptotic cells. Modulates cellular glycosphingolipid and cholesterol transport. May play a role in the internalization and endosomal trafficking of various LRP1 ligands, such as PSAP. Increases cellular levels of GTP-bound ARF6. {ECO:0000269|PubMed:10574763, ECO:0000269|PubMed:10574771, ECO:0000269|PubMed:16497666, ECO:0000269|PubMed:17398097}. This is the function of ENSG00000144366 (GULP1, GULP PTB domain containing engulfment adaptor 1).