Recombinant Human Low-density lipoprotein receptor-related protein 2 (LRP2), partial

Function

Multiligand endocytic receptor (By similarity). Acts together with CUBN to mediate endocytosis of high-density lipoproteins (By similarity). Mediates receptor-mediated uptake of polybasic drugs such as aprotinin, aminoglycosides and polymyxin B (By similarity). In the kidney, mediates the tubular uptake and clearance of leptin (By similarity). Also mediates transport of leptin across the blood-brain barrier through endocytosis at the choroid plexus epithelium (By similarity). Endocytosis of leptin in neuronal cells is required for hypothalamic leptin signaling and leptin-mediated regulation of feeding and body weight (By similarity). Mediates endocytosis and subsequent lysosomal degradation of CST3 in kidney proximal tubule cells (By similarity). Mediates renal uptake of 25-hydroxyvitamin D3 in complex with the vitamin D3 transporter GC/DBP (By similarity). Mediates renal uptake of metallothionein-bound heavy metals (PubMed:15126248). Together with CUBN, mediates renal reabsorption of myoglobin (By similarity). Mediates renal uptake and subsequent lysosomal degradation of APOM (By similarity). Plays a role in kidney selenium homeostasis by mediating renal endocytosis of selenoprotein SEPP1 (By similarity). Mediates renal uptake of the antiapoptotic protein BIRC5/survivin which may be important for functional integrity of the kidney (PubMed:23825075). Mediates renal uptake of matrix metalloproteinase MMP2 in complex with metalloproteinase inhibitor TIMP1 (By similarity). Mediates endocytosis of Sonic hedgehog protein N-product (ShhN), the active product of SHH (By similarity). Also mediates ShhN transcytosis (By similarity). In the embryonic neuroepithelium, mediates endocytic uptake and degradation of BMP4, is required for correct SHH localization in the ventral neural tube and plays a role in patterning of the ventral telencephalon (By similarity). Required at the onset of neurulation to sequester SHH on the apical surface of neuroepithelial cells of the rostral diencephalon ventral midline and to control PTCH1-dependent uptake and intracellular trafficking of SHH (By similarity). During neurulation, required in neuroepithelial cells for uptake of folate bound to the folate receptor FOLR1 which is necessary for neural tube closure (By similarity). In the adult brain, negatively regulates BMP signaling in the subependymal zone which enables neurogenesis to proceed (By similarity). In astrocytes, mediates endocytosis of ALB which is required for the synthesis of the neurotrophic factor oleic acid (By similarity). Involved in neurite branching (By similarity). During optic nerve development, required for SHH-mediated migration and proliferation of oligodendrocyte precursor cells (By similarity). Mediates endocytic uptake and clearance of SHH in the retinal margin which protects retinal progenitor cells from mitogenic stimuli and keeps them quiescent (By similarity). Plays a role in reproductive organ development by mediating uptake in reproductive tissues of androgen and estrogen bound to the sex hormone binding protein SHBG (By similarity). Mediates endocytosis of angiotensin-2 (By similarity). Also mediates endocytosis of angiotensis 1-7 (By similarity). Binds to the complex composed of beta-amyloid protein 40 and CLU/APOJ and mediates its endocytosis and lysosomal degradation (By similarity). Required for embryonic heart development (By similarity). Required for normal hearing, possibly through interaction with estrogen in the inner ear (By similarity)

Subcellular Location

Apical cell membrane (Single-pass type I membrane protein); Endosome lumen; Membrane, coated pit; Cell projection, dendrite; Cell projection, axon

Disease Association

Donnai-Barrow syndrome (DBS) : An autosomal recessive syndrome characterized by complete or partial agenesis of the corpus callosum, congenital diaphragmatic hernia, facial dysmorphology, ocular anomalies, sensorineural hearing loss, developmental delay, and proteinuria. There is variability in the expression of some features, such as diaphragmatic hernia, corpus callosum anomalies and proteinuria. [The disease is caused by variants affecting the gene represented in this entry]

Tissue Specificity

Expressed in first and third trimester cytotrophoblasts in the placenta (at protein level) (PubMed:27798286). Absorptive epithelia, including renal proximal tubules

Subunit

Binds plasminogen, extracellular matrix components, plasminogen activator-plasminogen activator inhibitor type I complex, apolipoprotein E-enriched beta-VLDL, lipoprotein lipase, lactoferrin, CLU/clusterin and calcium (PubMed:7768901). Forms a multimeric complex together with LRPAP1 (PubMed:1400426). Interacts (via PxLPxI/L motif) with ANKRA2 (via ankyrin repeats) (By similarity). Interacts with LRP2BP (PubMed:12508107). Interacts (via NPXY motif) with DAB2; the interaction is not affected by tyrosine phosphorylation of the NPXY motif (PubMed:10769163, PubMed:15134832). Interacts with MB (By similarity). Interacts with BMP4 (By similarity). Interacts with the Sonic hedgehog protein N-product which is the active product of SHH (By similarity). Interacts with CST3 in a calcium-dependent manner (PubMed:17462596). Interacts with the vitamin-D binding protein GC/DBP (By similarity). Interacts with sex hormone-binding protein SHBG (PubMed:16143106). Interacts with angiotensin-2 (By similarity). Also interacts with angiotensin 1-7 (By similarity). Interacts with APOM (By similarity). Interacts with selenoprotein SEPP1 (By similarity). Interacts with LEP (By similarity). Interacts with ALB (By similarity). Interacts with the antiapoptotic protein BIRC5/survivin (PubMed:23825075). Interacts with matrix metalloproteinase MMP2 in complex with metalloproteinase inhibitor TIMP1 (By similarity). In neurons, forms a trimeric complex with APP and APPB1/FE65 (By similarity). Interacts with LDLRAP1/ARH; mediates trafficking of LRP2 to the endocytic recycling compartment (By similarity). Does not interact with beta-amyloid protein 40 alone but interacts with the complex composed of beta-amyloid protein 40 and CLU/APOJ (By similarity). Interacts with MDK (By similarity)

• Hjaelm G. et al. Cloning and sequencing of human gp330, a Ca(2+)-binding receptor with potential intracellular signaling properties. — Eur. J. Biochem. (1996)
• Hillier L.W. et al. Generation and annotation of the DNA sequences of human chromosomes 2 and 4. — Nature (2005)
• Korenberg J.R. et al. Chromosomal localization of human genes for the LDL receptor family member glycoprotein 330 (LRP2) and its associated protein RAP (LRPAP1). — Genomics (1994)
• Lundgren S. et al. A protein involved in calcium sensing of the human parathyroid and placental cytotrophoblast cells belongs to the LDL-receptor protein superfamily. — Exp. Cell Res. (1994)
• Kounnas M.Z. et al. The 39-kDa receptor-associated protein interacts with two members of the low density lipoprotein receptor family, alpha 2-macroglobulin receptor and glycoprotein 330. — J. Biol. Chem. (1992)
• Kounnas M.Z. et al. Identification of glycoprotein 330 as an endocytic receptor for apolipoprotein J/clusterin. — J. Biol. Chem. (1995)
• Oleinikov A.V. et al. Cytosolic adaptor protein Dab2 is an intracellular ligand of endocytic receptor gp600/megalin. — Biochem. J. (2000)
• Petersen H.H. et al. Functional interaction of megalin with the megalin-binding protein (MegBP), a novel tetratrico peptide repeat-containing adaptor molecule. — J. Cell Sci. (2003)