Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1996 Apr 2;133(2):281–291. doi: 10.1083/jcb.133.2.281

Isoforms of the invariant chain regulate transport of MHC class II molecules to antigen processing compartments

PMCID: PMC2120797  PMID: 8609162

Abstract

Newly synthesized class II molecules of the major histocompatibility complex must be transported to endosomal compartments where antigens are processed for presentation to class II-restricted T cells. The invariant chain (Ii), which assembles with newly synthesized class II alpha- and beta-chains in the endoplasmic reticulum, carries one or more targeting signals for transport to endosomal compartments where Ii dissociates from alpha beta Ii complexes. Here we show that the transport route of alpha beta Ii complexes is regulated selectively by two forms of Ii (p33 and p35) that are generated by the use of alternative translation initiation sites. Using a novel quantitative surface arrival assay based on labeling with [6-3H]-D-galactose combined with biochemical modification at the cell surface with neuraminidase, we demonstrate that newly synthesized alpha beta Ii molecules containing the Ii-p33 isoform can be detected on the cell surface shortly after passage through the Golgi apparatus/trans-Golgi network. A substantial amount of these alpha beta Ii complexes are targeted to early endosomes either directly from the trans-Golgi network or after internalization from the cell surface before their delivery to antigen processing compartments. The fraction of alpha beta Ii complexes containing the p35 isoform of Ii with a longer cytosolic domain was not detected at the cell surface as determined by iodination of intact cells and the lack of susceptibility to neuraminidase trimming on ice. However, treatment with neuraminidase at 37 degrees C did reveal that some of the alpha beta Ii-p35 complexes traversed early endosomes. These results demonstrate that a fraction of newly synthesized class II molecules arrive at the cell surface as alpha beta Ii complexes before delivery to antigen processing compartments and that class II alpha beta Ii complexes associated with the two isoforms of Ii are sorted to these compartments by different transport routes.

Full Text

The Full Text of this article is available as a PDF (2.0 MB).

Selected References

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

  1. Amigorena S., Drake J. R., Webster P., Mellman I. Transient accumulation of new class II MHC molecules in a novel endocytic compartment in B lymphocytes. Nature. 1994 May 12;369(6476):113–120. doi: 10.1038/369113a0. [DOI] [PubMed] [Google Scholar]
  2. Amigorena S., Webster P., Drake J., Newcomb J., Cresswell P., Mellman I. Invariant chain cleavage and peptide loading in major histocompatibility complex class II vesicles. J Exp Med. 1995 May 1;181(5):1729–1741. doi: 10.1084/jem.181.5.1729. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Arneson L. S., Miller J. Efficient endosomal localization of major histocompatibility complex class II-invariant chain complexes requires multimerization of the invariant chain targeting sequence. J Cell Biol. 1995 Jun;129(5):1217–1228. doi: 10.1083/jcb.129.5.1217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Blum J. S., Cresswell P. Role for intracellular proteases in the processing and transport of class II HLA antigens. Proc Natl Acad Sci U S A. 1988 Jun;85(11):3975–3979. doi: 10.1073/pnas.85.11.3975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bremnes B., Madsen T., Gedde-Dahl M., Bakke O. An LI and ML motif in the cytoplasmic tail of the MHC-associated invariant chain mediate rapid internalization. J Cell Sci. 1994 Jul;107(Pt 7):2021–2032. doi: 10.1242/jcs.107.7.2021. [DOI] [PubMed] [Google Scholar]
  6. Bénaroch P., Yilla M., Raposo G., Ito K., Miwa K., Geuze H. J., Ploegh H. L. How MHC class II molecules reach the endocytic pathway. EMBO J. 1995 Jan 3;14(1):37–49. doi: 10.1002/j.1460-2075.1995.tb06973.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Castellino F., Germain R. N. Extensive trafficking of MHC class II-invariant chain complexes in the endocytic pathway and appearance of peptide-loaded class II in multiple compartments. Immunity. 1995 Jan;2(1):73–88. doi: 10.1016/1074-7613(95)90080-2. [DOI] [PubMed] [Google Scholar]
  8. Duncan J. R., Kornfeld S. Intracellular movement of two mannose 6-phosphate receptors: return to the Golgi apparatus. J Cell Biol. 1988 Mar;106(3):617–628. doi: 10.1083/jcb.106.3.617. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fukuda M. Lysosomal membrane glycoproteins. Structure, biosynthesis, and intracellular trafficking. J Biol Chem. 1991 Nov 15;266(32):21327–21330. [PubMed] [Google Scholar]
  10. Futter C. E., Connolly C. N., Cutler D. F., Hopkins C. R. Newly synthesized transferrin receptors can be detected in the endosome before they appear on the cell surface. J Biol Chem. 1995 May 5;270(18):10999–11003. doi: 10.1074/jbc.270.18.10999. [DOI] [PubMed] [Google Scholar]
  11. Germain R. N. MHC-dependent antigen processing and peptide presentation: providing ligands for T lymphocyte activation. Cell. 1994 Jan 28;76(2):287–299. doi: 10.1016/0092-8674(94)90336-0. [DOI] [PubMed] [Google Scholar]
  12. Guy K., Van Heyningen V., Cohen B. B., Deane D. L., Steel C. M. Differential expression and serologically distinct subpopulations of human Ia antigens detected with monoclonal antibodies to Ia alpha and beta chains. Eur J Immunol. 1982 Nov;12(11):942–948. doi: 10.1002/eji.1830121109. [DOI] [PubMed] [Google Scholar]
  13. Harding C. V., Unanue E. R. Quantitation of antigen-presenting cell MHC class II/peptide complexes necessary for T-cell stimulation. Nature. 1990 Aug 9;346(6284):574–576. doi: 10.1038/346574a0. [DOI] [PubMed] [Google Scholar]
  14. Harding C. V., Unanue E. R., Slot J. W., Schwartz A. L., Geuze H. J. Functional and ultrastructural evidence for intracellular formation of major histocompatibility complex class II-peptide complexes during antigen processing. Proc Natl Acad Sci U S A. 1990 Jul;87(14):5553–5557. doi: 10.1073/pnas.87.14.5553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Harter C., Mellman I. Transport of the lysosomal membrane glycoprotein lgp120 (lgp-A) to lysosomes does not require appearance on the plasma membrane. J Cell Biol. 1992 Apr;117(2):311–325. doi: 10.1083/jcb.117.2.311. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Karp D. R., Teletski C. L., Jaraquemada D., Maloy W. L., Coligan J. E., Long E. O. Structural requirements for pairing of alpha and beta chains in HLA-DR and HLA-DP molecules. J Exp Med. 1990 Mar 1;171(3):615–628. doi: 10.1084/jem.171.3.615. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kavathas P., Bach F. H., DeMars R. Gamma ray-induced loss of expression of HLA and glyoxalase I alleles in lymphoblastoid cells. Proc Natl Acad Sci U S A. 1980 Jul;77(7):4251–4255. doi: 10.1073/pnas.77.7.4251. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kleijmeer M. J., Ossevoort M. A., van Veen C. J., van Hellemond J. J., Neefjes J. J., Kast W. M., Melief C. J., Geuze H. J. MHC class II compartments and the kinetics of antigen presentation in activated mouse spleen dendritic cells. J Immunol. 1995 Jun 1;154(11):5715–5724. [PubMed] [Google Scholar]
  19. Klumperman J., Hille A., Veenendaal T., Oorschot V., Stoorvogel W., von Figura K., Geuze H. J. Differences in the endosomal distributions of the two mannose 6-phosphate receptors. J Cell Biol. 1993 Jun;121(5):997–1010. doi: 10.1083/jcb.121.5.997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Kornfeld R., Kornfeld S. Assembly of asparagine-linked oligosaccharides. Annu Rev Biochem. 1985;54:631–664. doi: 10.1146/annurev.bi.54.070185.003215. [DOI] [PubMed] [Google Scholar]
  21. Kornfeld S., Mellman I. The biogenesis of lysosomes. Annu Rev Cell Biol. 1989;5:483–525. doi: 10.1146/annurev.cb.05.110189.002411. [DOI] [PubMed] [Google Scholar]
  22. Kvist S., Wiman K., Claesson L., Peterson P. A., Dobberstein B. Membrane insertion and oligomeric assembly of HLA-DR histocompatibility antigens. Cell. 1982 May;29(1):61–69. doi: 10.1016/0092-8674(82)90090-3. [DOI] [PubMed] [Google Scholar]
  23. Lamb C. A., Cresswell P. Assembly and transport properties of invariant chain trimers and HLA-DR-invariant chain complexes. J Immunol. 1992 Jun 1;148(11):3478–3482. [PubMed] [Google Scholar]
  24. Letourneur F., Klausner R. D. A novel di-leucine motif and a tyrosine-based motif independently mediate lysosomal targeting and endocytosis of CD3 chains. Cell. 1992 Jun 26;69(7):1143–1157. doi: 10.1016/0092-8674(92)90636-q. [DOI] [PubMed] [Google Scholar]
  25. Ludwig T., Griffiths G., Hoflack B. Distribution of newly synthesized lysosomal enzymes in the endocytic pathway of normal rat kidney cells. J Cell Biol. 1991 Dec;115(6):1561–1572. doi: 10.1083/jcb.115.6.1561. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Machamer C. E., Cresswell P. Biosynthesis and glycosylation of the invariant chain associated with HLA-DR antigens. J Immunol. 1982 Dec;129(6):2564–2569. [PubMed] [Google Scholar]
  27. Machamer C. E., Cresswell P. Monensin prevents terminal glycosylation of the N- and O-linked oligosaccharides of the HLA-DR-associated invariant chain and inhibits its dissociation from the alpha-beta chain complex. Proc Natl Acad Sci U S A. 1984 Mar;81(5):1287–1291. doi: 10.1073/pnas.81.5.1287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Marić M. A., Taylor M. D., Blum J. S. Endosomal aspartic proteinases are required for invariant-chain processing. Proc Natl Acad Sci U S A. 1994 Mar 15;91(6):2171–2175. doi: 10.1073/pnas.91.6.2171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Marks M. S., Blum J. S., Cresswell P. Invariant chain trimers are sequestered in the rough endoplasmic reticulum in the absence of association with HLA class II antigens. J Cell Biol. 1990 Sep;111(3):839–855. doi: 10.1083/jcb.111.3.839. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Neefjes J. J., Stollorz V., Peters P. J., Geuze H. J., Ploegh H. L. The biosynthetic pathway of MHC class II but not class I molecules intersects the endocytic route. Cell. 1990 Apr 6;61(1):171–183. doi: 10.1016/0092-8674(90)90224-3. [DOI] [PubMed] [Google Scholar]
  31. Newcomb J. R., Cresswell P. Characterization of endogenous peptides bound to purified HLA-DR molecules and their absence from invariant chain-associated alpha beta dimers. J Immunol. 1993 Jan 15;150(2):499–507. [PubMed] [Google Scholar]
  32. Newcomb J. R., Cresswell P. Structural analysis of proteolytic products of MHC class II-invariant chain complexes generated in vivo. J Immunol. 1993 Oct 15;151(8):4153–4163. [PubMed] [Google Scholar]
  33. Odorizzi C. G., Trowbridge I. S., Xue L., Hopkins C. R., Davis C. D., Collawn J. F. Sorting signals in the MHC class II invariant chain cytoplasmic tail and transmembrane region determine trafficking to an endocytic processing compartment. J Cell Biol. 1994 Jul;126(2):317–330. doi: 10.1083/jcb.126.2.317. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Ogata S., Fukuda M. Lysosomal targeting of Limp II membrane glycoprotein requires a novel Leu-Ile motif at a particular position in its cytoplasmic tail. J Biol Chem. 1994 Feb 18;269(7):5210–5217. [PubMed] [Google Scholar]
  35. Pearse B. M., Robinson M. S. Clathrin, adaptors, and sorting. Annu Rev Cell Biol. 1990;6:151–171. doi: 10.1146/annurev.cb.06.110190.001055. [DOI] [PubMed] [Google Scholar]
  36. Peters P. J., Neefjes J. J., Oorschot V., Ploegh H. L., Geuze H. J. Segregation of MHC class II molecules from MHC class I molecules in the Golgi complex for transport to lysosomal compartments. Nature. 1991 Feb 21;349(6311):669–676. doi: 10.1038/349669a0. [DOI] [PubMed] [Google Scholar]
  37. Peters P. J., Raposo G., Neefjes J. J., Oorschot V., Leijendekker R. L., Geuze H. J., Ploegh H. L. Major histocompatibility complex class II compartments in human B lymphoblastoid cells are distinct from early endosomes. J Exp Med. 1995 Aug 1;182(2):325–334. doi: 10.1084/jem.182.2.325. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Pieters J., Bakke O., Dobberstein B. The MHC class II-associated invariant chain contains two endosomal targeting signals within its cytoplasmic tail. J Cell Sci. 1993 Nov;106(Pt 3):831–846. doi: 10.1242/jcs.106.3.831. [DOI] [PubMed] [Google Scholar]
  39. Pieters J., Horstmann H., Bakke O., Griffiths G., Lipp J. Intracellular transport and localization of major histocompatibility complex class II molecules and associated invariant chain. J Cell Biol. 1991 Dec;115(5):1213–1223. doi: 10.1083/jcb.115.5.1213. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Qiu Y., Xu X., Wandinger-Ness A., Dalke D. P., Pierce S. K. Separation of subcellular compartments containing distinct functional forms of MHC class II. J Cell Biol. 1994 May;125(3):595–605. doi: 10.1083/jcb.125.3.595. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. 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]
  42. Roche P. A., Cresswell P. Proteolysis of the class II-associated invariant chain generates a peptide binding site in intracellular HLA-DR molecules. Proc Natl Acad Sci U S A. 1991 Apr 15;88(8):3150–3154. doi: 10.1073/pnas.88.8.3150. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Roche P. A., Marks M. S., Cresswell P. Formation of a nine-subunit complex by HLA class II glycoproteins and the invariant chain. Nature. 1991 Dec 5;354(6352):392–394. doi: 10.1038/354392a0. [DOI] [PubMed] [Google Scholar]
  44. Roche P. A., Teletski C. L., Karp D. R., Pinet V., Bakke O., Long E. O. Stable surface expression of invariant chain prevents peptide presentation by HLA-DR. EMBO J. 1992 Aug;11(8):2841–2847. doi: 10.1002/j.1460-2075.1992.tb05351.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Roche P. A., Teletski C. L., Stang E., Bakke O., Long E. O. Cell surface HLA-DR-invariant chain complexes are targeted to endosomes by rapid internalization. Proc Natl Acad Sci U S A. 1993 Sep 15;90(18):8581–8585. doi: 10.1073/pnas.90.18.8581. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Romagnoli P., Layet C., Yewdell J., Bakke O., Germain R. N. Relationship between invariant chain expression and major histocompatibility complex class II transport into early and late endocytic compartments. J Exp Med. 1993 Mar 1;177(3):583–596. doi: 10.1084/jem.177.3.583. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Roth J., Berger E. G. Immunocytochemical localization of galactosyltransferase in HeLa cells: codistribution with thiamine pyrophosphatase in trans-Golgi cisternae. J Cell Biol. 1982 Apr;93(1):223–229. doi: 10.1083/jcb.93.1.223. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Rudensky A. Y., Maric M., Eastman S., Shoemaker L., DeRoos P. C., Blum J. S. Intracellular assembly and transport of endogenous peptide-MHC class II complexes. Immunity. 1994 Oct;1(7):585–594. doi: 10.1016/1074-7613(94)90048-5. [DOI] [PubMed] [Google Scholar]
  49. Schutze M. P., Peterson P. A., Jackson M. R. An N-terminal double-arginine motif maintains type II membrane proteins in the endoplasmic reticulum. EMBO J. 1994 Apr 1;13(7):1696–1705. doi: 10.1002/j.1460-2075.1994.tb06434.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Strubin M., Long E. O., Mach B. Two forms of the Ia antigen-associated invariant chain result from alternative initiations at two in-phase AUGs. Cell. 1986 Nov 21;47(4):619–625. doi: 10.1016/0092-8674(86)90626-4. [DOI] [PubMed] [Google Scholar]
  51. Tulp A., Verwoerd D., Dobberstein B., Ploegh H. L., Pieters J. Isolation and characterization of the intracellular MHC class II compartment. Nature. 1994 May 12;369(6476):120–126. doi: 10.1038/369120a0. [DOI] [PubMed] [Google Scholar]
  52. West M. A., Lucocq J. M., Watts C. Antigen processing and class II MHC peptide-loading compartments in human B-lymphoblastoid cells. Nature. 1994 May 12;369(6476):147–151. doi: 10.1038/369147a0. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES