Skip to main content
PMC home page
The EMBO Journal logoLink to The EMBO Journal
. 1996 Jun 3;15(11):2632–2639.

RAP, a specialized chaperone, prevents ligand-induced ER retention and degradation of LDL receptor-related endocytic receptors.

T E Willnow 1, A Rohlmann 1, J Horton 1, H Otani 1, J R Braun 1, R E Hammer 1, J Herz 1
PMCID: PMC450198  PMID: 8654360

Abstract

The multifunctional low density lipoprotein (LDL) receptor-related protein (LRP) forms a complex with a receptor-associated protein (RAP) within the secretory pathway. RAP inhibits ligand binding to LRP and is required for normal functional expression of LRP in vivo, suggesting a physiological function as a specialized chaperone. We have used RAP-deficient mice, generated by gene targeting, to investigate the role of RAP in the biosynthesis and biological activity of LRP and other members of the LDL receptor gene family in various organs and in embryonic fibroblasts. Our results demonstrate that RAP is required for the proper folding and export of the receptors from the endoplasmic reticulum (ER) by preventing the premature binding of co-expressed ligands. Overexpression of apolipoprotein E (apoE), a high affinity ligand for LRP, results in dramatically reduced cellular LRP expression, an effect that is prevented by co-expression of RAP. RAP thus defines a novel class of molecular chaperones that selectively protect endocytic receptors by binding to newly synthesized receptor polypeptides, thereby preventing ligand-induced aggregation and subsequent degradation in the ER.

Full text

PDF
2639

Images in this article

2633Image
on p.2633
2633Image
on p.2633
2634Image
on p.2634
2635Image
on p.2635
2635Image
on p.2635
2636Image
on p.2636
2636Image
on p.2636
2637Image
on p.2637

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bartles J. R., Hubbard A. L. Biogenesis of the rat hepatocyte plasma membrane. Methods Enzymol. 1990;191:825–841. doi: 10.1016/0076-6879(90)91050-g. [DOI] [PubMed] [Google Scholar]
  2. Battey F. D., Gåfvels M. E., FitzGerald D. J., Argraves W. S., Chappell D. A., Strauss J. F., 3rd, Strickland D. K. The 39-kDa receptor-associated protein regulates ligand binding by the very low density lipoprotein receptor. J Biol Chem. 1994 Sep 16;269(37):23268–23273. [PubMed] [Google Scholar]
  3. Biemesderfer D., Dekan G., Aronson P. S., Farquhar M. G. Biosynthesis of the gp330/44-kDa Heymann nephritis antigenic complex: assembly takes place in the ER. Am J Physiol. 1993 Jun;264(6 Pt 2):F1011–F1020. doi: 10.1152/ajprenal.1993.264.6.F1011. [DOI] [PubMed] [Google Scholar]
  4. Bijlmakers M. J., Benaroch P., Ploegh H. L. Assembly of HLA DR1 molecules translated in vitro: binding of peptide in the endoplasmic reticulum precludes association with invariant chain. EMBO J. 1994 Jun 1;13(11):2699–2707. doi: 10.1002/j.1460-2075.1994.tb06560.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Boyles J. K., Pitas R. E., Wilson E., Mahley R. W., Taylor J. M. Apolipoprotein E associated with astrocytic glia of the central nervous system and with nonmyelinating glia of the peripheral nervous system. J Clin Invest. 1985 Oct;76(4):1501–1513. doi: 10.1172/JCI112130. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Braks J. A., Martens G. J. 7B2 is a neuroendocrine chaperone that transiently interacts with prohormone convertase PC2 in the secretory pathway. Cell. 1994 Jul 29;78(2):263–273. doi: 10.1016/0092-8674(94)90296-8. [DOI] [PubMed] [Google Scholar]
  7. Bu G., Geuze H. J., Strous G. J., Schwartz A. L. 39 kDa receptor-associated protein is an ER resident protein and molecular chaperone for LDL receptor-related protein. EMBO J. 1995 May 15;14(10):2269–2280. doi: 10.1002/j.1460-2075.1995.tb07221.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Bu G., Williams S., Strickland D. K., Schwartz A. L. Low density lipoprotein receptor-related protein/alpha 2-macroglobulin receptor is an hepatic receptor for tissue-type plasminogen activator. Proc Natl Acad Sci U S A. 1992 Aug 15;89(16):7427–7431. doi: 10.1073/pnas.89.16.7427. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fraker P. J., Speck J. C., Jr Protein and cell membrane iodinations with a sparingly soluble chloroamide, 1,3,4,6-tetrachloro-3a,6a-diphrenylglycoluril. Biochem Biophys Res Commun. 1978 Feb 28;80(4):849–857. doi: 10.1016/0006-291x(78)91322-0. [DOI] [PubMed] [Google Scholar]
  10. Frykman P. K., Brown M. S., Yamamoto T., Goldstein J. L., Herz J. Normal plasma lipoproteins and fertility in gene-targeted mice homozygous for a disruption in the gene encoding very low density lipoprotein receptor. Proc Natl Acad Sci U S A. 1995 Aug 29;92(18):8453–8457. doi: 10.1073/pnas.92.18.8453. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Goldstein J. L., Basu S. K., Brown M. S. Receptor-mediated endocytosis of low-density lipoprotein in cultured cells. Methods Enzymol. 1983;98:241–260. doi: 10.1016/0076-6879(83)98152-1. [DOI] [PubMed] [Google Scholar]
  12. Herz J., Goldstein J. L., Strickland D. K., Ho Y. K., Brown M. S. 39-kDa protein modulates binding of ligands to low density lipoprotein receptor-related protein/alpha 2-macroglobulin receptor. J Biol Chem. 1991 Nov 5;266(31):21232–21238. [PubMed] [Google Scholar]
  13. Herz J., Hamann U., Rogne S., Myklebost O., Gausepohl H., Stanley K. K. Surface location and high affinity for calcium of a 500-kd liver membrane protein closely related to the LDL-receptor suggest a physiological role as lipoprotein receptor. EMBO J. 1988 Dec 20;7(13):4119–4127. doi: 10.1002/j.1460-2075.1988.tb03306.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Herz J., Kowal R. C., Goldstein J. L., Brown M. S. Proteolytic processing of the 600 kd low density lipoprotein receptor-related protein (LRP) occurs in a trans-Golgi compartment. EMBO J. 1990 Jun;9(6):1769–1776. doi: 10.1002/j.1460-2075.1990.tb08301.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Kerjaschki D., Farquhar M. G. Immunocytochemical localization of the Heymann nephritis antigen (GP330) in glomerular epithelial cells of normal Lewis rats. J Exp Med. 1983 Feb 1;157(2):667–686. doi: 10.1084/jem.157.2.667. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Kopfler W. P., Willard M., Betz T., Willard J. E., Gerard R. D., Meidell R. S. Adenovirus-mediated transfer of a gene encoding human apolipoprotein A-I into normal mice increases circulating high-density lipoprotein cholesterol. Circulation. 1994 Sep;90(3):1319–1327. doi: 10.1161/01.cir.90.3.1319. [DOI] [PubMed] [Google Scholar]
  17. Kounnas M. Z., Moir R. D., Rebeck G. W., Bush A. I., Argraves W. S., Tanzi R. E., Hyman B. T., Strickland D. K. LDL receptor-related protein, a multifunctional ApoE receptor, binds secreted beta-amyloid precursor protein and mediates its degradation. Cell. 1995 Jul 28;82(2):331–340. doi: 10.1016/0092-8674(95)90320-8. [DOI] [PubMed] [Google Scholar]
  18. Krieger M., Herz J. Structures and functions of multiligand lipoprotein receptors: macrophage scavenger receptors and LDL receptor-related protein (LRP). Annu Rev Biochem. 1994;63:601–637. doi: 10.1146/annurev.bi.63.070194.003125. [DOI] [PubMed] [Google Scholar]
  19. Kristensen T., Moestrup S. K., Gliemann J., Bendtsen L., Sand O., Sottrup-Jensen L. Evidence that the newly cloned low-density-lipoprotein receptor related protein (LRP) is the alpha 2-macroglobulin receptor. FEBS Lett. 1990 Dec 10;276(1-2):151–155. doi: 10.1016/0014-5793(90)80530-v. [DOI] [PubMed] [Google Scholar]
  20. Moestrup S. K., Cui S., Vorum H., Bregengård C., Bjørn S. E., Norris K., Gliemann J., Christensen E. I. Evidence that epithelial glycoprotein 330/megalin mediates uptake of polybasic drugs. J Clin Invest. 1995 Sep;96(3):1404–1413. doi: 10.1172/JCI118176. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Mokuno H., Brady S., Kotite L., Herz J., Havel R. J. Effect of the 39-kDa receptor-associated protein on the hepatic uptake and endocytosis of chylomicron remnants and low density lipoproteins in the rat. J Biol Chem. 1994 May 6;269(18):13238–13243. [PubMed] [Google Scholar]
  22. Narita M., Bu G., Herz J., Schwartz A. L. Two receptor systems are involved in the plasma clearance of tissue-type plasminogen activator (t-PA) in vivo. J Clin Invest. 1995 Aug;96(2):1164–1168. doi: 10.1172/JCI118105. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Orlando R. A., Kerjaschki D., Kurihara H., Biemesderfer D., Farquhar M. G. gp330 associates with a 44-kDa protein in the rat kidney to form the Heymann nephritis antigenic complex. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):6698–6702. doi: 10.1073/pnas.89.15.6698. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Piedrahita J. A., Zhang S. H., Hagaman J. R., Oliver P. M., Maeda N. Generation of mice carrying a mutant apolipoprotein E gene inactivated by gene targeting in embryonic stem cells. Proc Natl Acad Sci U S A. 1992 May 15;89(10):4471–4475. doi: 10.1073/pnas.89.10.4471. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Roche P. A., Cresswell P. Invariant chain association with HLA-DR molecules inhibits immunogenic peptide binding. Nature. 1990 Jun 14;345(6276):615–618. doi: 10.1038/345615a0. [DOI] [PubMed] [Google Scholar]
  26. Selkoe D. J. Cell biology of the amyloid beta-protein precursor and the mechanism of Alzheimer's disease. Annu Rev Cell Biol. 1994;10:373–403. doi: 10.1146/annurev.cb.10.110194.002105. [DOI] [PubMed] [Google Scholar]
  27. Strickland D. K., Ashcom J. D., Williams S., Burgess W. H., Migliorini M., Argraves W. S. Sequence identity between the alpha 2-macroglobulin receptor and low density lipoprotein receptor-related protein suggests that this molecule is a multifunctional receptor. J Biol Chem. 1990 Oct 15;265(29):17401–17404. [PubMed] [Google Scholar]
  28. Strittmatter W. J., Saunders A. M., Schmechel D., Pericak-Vance M., Enghild J., Salvesen G. S., Roses A. D. Apolipoprotein E: high-avidity binding to beta-amyloid and increased frequency of type 4 allele in late-onset familial Alzheimer disease. Proc Natl Acad Sci U S A. 1993 Mar 1;90(5):1977–1981. doi: 10.1073/pnas.90.5.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Teyton L., O'Sullivan D., Dickson P. W., Lotteau V., Sette A., Fink P., Peterson P. A. Invariant chain distinguishes between the exogenous and endogenous antigen presentation pathways. Nature. 1990 Nov 1;348(6296):39–44. doi: 10.1038/348039a0. [DOI] [PubMed] [Google Scholar]
  30. Tsirka S. E., Gualandris A., Amaral D. G., Strickland S. Excitotoxin-induced neuronal degeneration and seizure are mediated by tissue plasminogen activator. Nature. 1995 Sep 28;377(6547):340–344. doi: 10.1038/377340a0. [DOI] [PubMed] [Google Scholar]
  31. Viville S., Neefjes J., Lotteau V., Dierich A., Lemeur M., Ploegh H., Benoist C., Mathis D. Mice lacking the MHC class II-associated invariant chain. Cell. 1993 Feb 26;72(4):635–648. doi: 10.1016/0092-8674(93)90081-z. [DOI] [PubMed] [Google Scholar]
  32. Willnow T. E., Armstrong S. A., Hammer R. E., Herz J. Functional expression of low density lipoprotein receptor-related protein is controlled by receptor-associated protein in vivo. Proc Natl Acad Sci U S A. 1995 May 9;92(10):4537–4541. doi: 10.1073/pnas.92.10.4537. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Willnow T. E., Herz J. Genetic deficiency in low density lipoprotein receptor-related protein confers cellular resistance to Pseudomonas exotoxin A. Evidence that this protein is required for uptake and degradation of multiple ligands. J Cell Sci. 1994 Mar;107(Pt 3):719–726. [PubMed] [Google Scholar]
  34. Willnow T. E., Moehring J. M., Inocencio N. M., Moehring T. J., Herz J. The low-density-lipoprotein receptor-related protein (LRP) is processed by furin in vivo and in vitro. Biochem J. 1996 Jan 1;313(Pt 1):71–76. doi: 10.1042/bj3130071. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Willnow T. E., Orth K., Herz J. Molecular dissection of ligand binding sites on the low density lipoprotein receptor-related protein. J Biol Chem. 1994 Jun 3;269(22):15827–15832. [PubMed] [Google Scholar]
  36. Willnow T. E., Sheng Z., Ishibashi S., Herz J. Inhibition of hepatic chylomicron remnant uptake by gene transfer of a receptor antagonist. Science. 1994 Jun 3;264(5164):1471–1474. doi: 10.1126/science.7515194. [DOI] [PubMed] [Google Scholar]
  37. Wolf B. B., Lopes M. B., VandenBerg S. R., Gonias S. L. Characterization and immunohistochemical localization of alpha 2-macroglobulin receptor (low-density lipoprotein receptor-related protein) in human brain. Am J Pathol. 1992 Jul;141(1):37–42. [PMC free article] [PubMed] [Google Scholar]

Articles from The EMBO Journal are provided here courtesy of Nature Publishing Group

RESOURCES