Functions as a cell surface receptor and performs physiological functions on the surface of neurons relevant to neurite growth, neuronal adhesion and axonogenesis. Involved in cell mobility and transcription regulation through protein-protein interactions. Can promote transcription activation through binding to APBB1-KAT5 and inhibit Notch signaling through interaction with Numb. Couples to apoptosis-inducing pathways such as those mediated by G(O) and JIP. Inhibits G(o) alpha ATPase activity (By similarity). Acts as a kinesin I membrane receptor, mediating the axonal transport of beta-secretase and presenilin 1. May be involved in copper homeostasis/oxidative stress through copper ion reduction. Can regulate neurite outgrowth through binding to components of the extracellular matrix such as heparin and collagen I and IV (By similarity). The splice isoforms that contain the BPTI domain possess protease inhibitor activity. Induces a AGER-dependent pathway that involves activation of p38 MAPK, resulting in internalization of amyloid-beta peptide and leading to mitochondrial dysfunction in cultured cortical neurons (By similarity). Provides Cu(2+) ions for GPC1 which are required for release of nitric oxide (NO) and subsequent degradation of the heparan sulfate chains on GPC1.
Sequence Annotation
Topological domain: 18 699 Extracellular. Transmembrane: 700 723 Helical. Topological domain: 724 770 Cytoplasmic. Domain: 291 341 BPTI/Kunitz inhibitor. Region: 96 110 Heparin-binding. Region: 181 188 Zinc-binding. Region: 391 423 Heparin-binding. Region: 491 522 Heparin-binding. Region: 523 540 Collagen-binding. Region: 732 751 Interaction with G(o)-alpha. Region: 756 770 Interaction with DAB2. Motif: 724 734 Basolateral sorting signal. Motif: 759 762 NPXY motif; contains endocytosis signal. Metal binding site: 147 147 Copper 1. Metal binding site: 151 151 Copper 1. Metal binding site: 168 168 Copper 1. Metal binding site: 677 677 Copper or zinc 2. Metal binding site: 685 685 Copper or zinc 2. Functional site: 144 144 Required for Cu(2+) reduction. Functional site: 301 302 Reactive bond. Functional site: 671 672 Cleavage; by beta-secretase. Functional site: 672 673 Cleavage; by caspase-6. Functional site: 687 688 Cleavage; by alpha-secretase. Functional site: 690 691 Cleavage; by theta-secretase. Functional site: 704 704 Implicated in free radical propagation. Functional site: 711 712 Cleavage; by gamma-secretase; site 1. Functional site: 713 714 Cleavage; by gamma-secretase; site 2. Functional site: 720 721 Cleavage; by gamma-secretase; site 3. Functional site: 739 740 Cleavage; by caspase-6, caspase-8 orcaspase-9. Modified residue: 198 198 Phosphoserine; by CK2. Modified residue: 206 206 Phosphoserine; by CK1. Modified residue: 729 729 Phosphothreonine. Modified residue: 730 730 Phosphoserine; by APP-kinase I. Modified residue: 743 743 Phosphothreonine; by CDK5 and MAPK10. Modified residue: 757 757 Phosphotyrosine; by ABL1.