Cubilin

Cubilin is a protein that in humans is encoded by the CUBN gene.

CUBN
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 3KQ4
Identifiers
Aliases	CUBN, IFCR, MGA1, gp280, cubilin, IGS, IGS1
External IDs	OMIM: 602997; MGI: 1931256; HomoloGene: 37434; GeneCards: CUBN; OMA:CUBN - orthologs
Gene location (Human) Chr. Chromosome 10 (human) Band 10p13 Start 16,823,966 bp End 17,129,811 bp
Gene location (Mouse) Chr. Chromosome 2 (mouse) Band 2 A1|2 9.86 cM Start 13,281,149 bp End 13,496,624 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in kidney tubule glomerulus renal medulla metanephric glomerulus sperm oocyte right uterine tube human kidney gonad secondary oocyte Top expressed in primitive streak yolk sac ileum human kidney epithelium of small intestine intestinal villus jejunum epithelium of lens Ileal epithelium right kidney More reference expression data BioGPS More reference expression data
Gene ontology Molecular function calcium ion binding protein homodimerization activity protein binding transporter activity cobalamin binding metal ion binding channel regulator activity hemoglobin binding signaling receptor activity cargo receptor activity Cellular component brush border extrinsic component of external side of plasma membrane endoplasmic reticulum clathrin-coated pit lysosomal membrane cytoplasm Golgi apparatus endosome apical part of cell lysosome lysosomal lumen membrane cytosol extracellular exosome endocytic vesicle endosome membrane plasma membrane apical plasma membrane brush border membrane Golgi-associated vesicle ionotropic glutamate receptor complex coated vesicle endocytic vesicle membrane neuron projection membrane synapse Biological process tissue homeostasis cobalamin transport lipid metabolism protein transport cholesterol metabolic process vitamin D metabolic process cobalamin metabolic process steroid metabolic process endocytosis lipoprotein transport receptor-mediated endocytosis high-density lipoprotein particle clearance transport in utero embryonic development thigmotaxis hyperosmotic response response to nutrient adult locomotory behavior response to bacterium endocytic hemoglobin import into cell regulation of locomotion cobalamin catabolic process positive regulation of synaptic transmission, glutamatergic protein homotrimerization Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 8029 65969 Ensembl ENSG00000107611 ENSMUSG00000026726 UniProt O60494 Q9JLB4 RefSeq (mRNA) NM_001081 NM_001081084 RefSeq (protein) NP_001072 NP_001074553 Location (UCSC) Chr 10: 16.82 – 17.13 Mb Chr 2: 13.28 – 13.5 Mb PubMed search
Wikidata
View/Edit Human View/Edit Mouse

Function

Cubilin (CUBN) acts as a receptor for intrinsic factor-vitamin B₁₂ complexes. The role of receptor is supported by the presence of 27 CUB domains. Cubilin shows a restricted mode of expression according to protein profiling and transcriptomics analyses, and is essentially only present in the kidneys and small intestine. Mutations in CUBN may play a role in autosomal recessive megaloblastic anemia. A complex of amnionless and cubilin forms the cubam receptor.

Clinical significance

Cubilin is a potential diagnostic and prognostic cancer biomarker for kidney cancer. Based on patient survival data, high levels of cubilin in tumor cells is a favourable prognostic biomarker in renal cell carcinoma.

Further reading

• Christensen EI, Birn H (2002). "Megalin and cubilin: multifunctional endocytic receptors". Nat. Rev. Mol. Cell Biol. 3 (4): 256–66. doi:10.1038/nrm778. PMID 11994745. S2CID 21893726.
• Bork P, Beckmann G (1993). "The CUB domain. A widespread module in developmentally regulated proteins". J. Mol. Biol. 231 (2): 539–45. doi:10.1006/jmbi.1993.1305. PMID 8510165.
• Birn H, Verroust PJ, Nexo E, et al. (1997). "Characterization of an epithelial approximately 460-kDa protein that facilitates endocytosis of intrinsic factor-vitamin B₁₂ and binds receptor-associated protein". J. Biol. Chem. 272 (42): 26497–504. doi:10.1074/jbc.272.42.26497. PMID 9334227.
• Batuman V, Verroust PJ, Navar GL, et al. (1998). "Myeloma light chains are ligands for cubilin (gp280)". Am. J. Physiol. 275 (2 Pt 2): F246–54. doi:10.1152/ajprenal.1998.275.2.F246. PMID 9691015.
• Lindblom A, Quadt N, Marsh T, et al. (1999). "The intrinsic factor-vitamin B₁₂ receptor, cubilin, is assembled into trimers via a coiled-coil alpha-helix". J. Biol. Chem. 274 (10): 6374–80. doi:10.1074/jbc.274.10.6374. PMID 10037728.
• Aminoff M, Carter JE, Chadwick RB, et al. (1999). "Mutations in CUBN, encoding the intrinsic factor-vitamin B₁₂ receptor, cubilin, cause hereditary megaloblastic anaemia 1". Nat. Genet. 21 (3): 309–13. doi:10.1038/6831. PMID 10080186. S2CID 21836060.
• Kozyraki R, Fyfe J, Kristiansen M, et al. (1999). "The intrinsic factor-vitamin B₁₂ receptor, cubilin, is a high-affinity apolipoprotein A-I receptor facilitating endocytosis of high-density lipoprotein". Nat. Med. 5 (6): 656–61. doi:10.1038/9504. PMID 10371504. S2CID 9392624.
• Xu D, Kozyraki R, Newman TC, Fyfe JC (1999). "Genetic evidence of an accessory activity required specifically for cubilin brush-border expression and intrinsic factor-cobalamin absorption". Blood. 94 (10): 3604–6. doi:10.1182/blood.V94.10.3604.422k22_3604_3606. PMID 10552972.
• Birn H, Fyfe JC, Jacobsen C, et al. (2000). "Cubilin is an albumin binding protein important for renal tubular albumin reabsorption". J. Clin. Invest. 105 (10): 1353–61. doi:10.1172/JCI8862. PMC 315466. PMID 10811843.
• Kristiansen M, Aminoff M, Jacobsen C, et al. (2000). "Cubilin P1297L mutation associated with hereditary megaloblastic anemia 1 causes impaired recognition of intrinsic factor-vitamin B(12) by cubilin". Blood. 96 (2): 405–9. doi:10.1182/blood.V96.2.405. PMID 10887099.
• Yammani RR, Seetharam S, Seetharam B (2001). "Cubilin and megalin expression and their interaction in the rat intestine: effect of thyroidectomy". Am. J. Physiol. Endocrinol. Metab. 281 (5): E900–7. doi:10.1152/ajpendo.2001.281.5.E900. PMID 11595644. S2CID 1438500.
• Kozyraki R, Fyfe J, Verroust PJ, et al. (2001). "Megalin-dependent cubilin-mediated endocytosis is a major pathway for the apical uptake of transferrin in polarized epithelia". Proc. Natl. Acad. Sci. U.S.A. 98 (22): 12491–6. Bibcode:2001PNAS...9812491K. doi:10.1073/pnas.211291398. PMC 60081. PMID 11606717.
• Nykjaer A, Fyfe JC, Kozyraki R, et al. (2002). "Cubilin dysfunction causes abnormal metabolism of the steroid hormone 25(OH) vitamin D(3)". Proc. Natl. Acad. Sci. U.S.A. 98 (24): 13895–900. doi:10.1073/pnas.241516998. PMC 61138. PMID 11717447.
• Fedosov SN, Berglund L, Fedosova NU, et al. (2002). "Comparative analysis of cobalamin binding kinetics and ligand protection for intrinsic factor, transcobalamin, and haptocorrin". J. Biol. Chem. 277 (12): 9989–96. doi:10.1074/jbc.M111399200. PMID 11788601.
• Crider-Pirkle S, Billingsley P, Faust C, et al. (2002). "Cubilin, a binding partner for galectin-3 in the murine utero-placental complex". J. Biol. Chem. 277 (18): 15904–12. doi:10.1074/jbc.M200331200. PMID 11856751.
• Wahlstedt-Fröberg V, Pettersson T, Aminoff M, et al. (2004). "Proteinuria in cubilin-deficient patients with selective vitamin B₁₂ malabsorption". Pediatr. Nephrol. 18 (5): 417–21. doi:10.1007/s00467-003-1128-y. PMID 12687456. S2CID 10669019.
• Smith BT, Mussell, JC, Fleming, PA, Barth, JL, Spyropoulos, DD, Cooley, MA, Drake, CJ, Argraves, WS (2006). "Targeted disruption of cubilin reveals essential developmental roles in the structure and function of endoderm and in somite formation". BMC Developmental Biology. 6: 30. doi:10.1186/1471-213X-6-30. PMC 1533814. PMID 16787536.

External links

• Overview of all the structural information available in the PDB for UniProt: O60494 (Cubilin) at the PDBe-KB.