Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1991 Apr 1;113(1):207–221. doi: 10.1083/jcb.113.1.207

Human keratinocytes express a new CD44 core protein (CD44E) as a heparan-sulfate intrinsic membrane proteoglycan with additional exons

PMCID: PMC2288920  PMID: 2007624

Abstract

We previously identified a 90-kD (GP90), collagen-binding, membrane glycoprotein, termed extracellular matrix receptor III (ECMR III), that is homologous to the lymphocyte homing receptor and CD44 antigen (Gallatin, W. M., E. A. Wayner, P. A. Hoffman, T. St. John, E. C. Butcher, and W. G. Carter. 1989. Proc. Natl. Acad. Sci. USA. 86:4654- 4658). CD44 is abundantly expressed in many epithelial tissues, and is localized predominantly to filopodia in cultured keratinocytes. Here we establish CD44 as a polymorphic family of related membrane proteoglycans and glycoproteins possessing extensive diversity in both glycosylation and core protein sequence. Human neonatal foreskin keratinocytes (HFKs) and QG56 lung squamous carcinoma cells express an alternatively spliced form of the CD44 core protein (termed CD44E) that contains an additional 132 amino acids in the carbohydrate attachment region of the extracellular domain. HFKs, HT1080 fibrosarcoma and QG56 cells, as well as many other human cells, contain varying ratios of GP90 and structurally related, higher molecular mass forms of CD44 that express the following characteristics: (a) each form reacted with anti- CD44 (mAbs) P1G12, P3H9, and P3H5. Each of these mAbs recognized a distinct, nonoverlapping epitope present on each CD44 form. (b) Differences in mass were due primarily to variation in carbohydrate moieties, including sulfated aspargine-linked glycopeptides (GP), chondroitin sulfate (CS), and heparan sulfate (HS) glycosaminoglycans, as well as O-linked mucin and polylactosamine structure(s). The major polymorphic forms were designated HT1080 GP90 and CS180, QG56 GP230, and HFK HS/CS250, based on dominant carbohydrate moieties and relative mass. (c) The polymorphic forms use CD44 and CD44E core proteins, each containing a unique set of potential attachment sites for O- and N- glycosides and glycosaminoglycans. (d) Immunofluorescence microscopy, differential extraction with Triton-X-114 detergent, and incorporation into liposomes indicated that all the forms were membrane bound glycoconjugates. These results define CD44 as a structurally diverse, but immunologically related, set of intrinsic membrane macromolecules, and suggests that these structurally varied forms might be expected to manifest multiple functions.

Full Text

The Full Text of this article is available as a PDF (4.0 MB).

Selected References

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

  1. Alho A. M., Underhill C. B. The hyaluronate receptor is preferentially expressed on proliferating epithelial cells. J Cell Biol. 1989 Apr;108(4):1557–1565. doi: 10.1083/jcb.108.4.1557. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Aruffo A., Stamenkovic I., Melnick M., Underhill C. B., Seed B. CD44 is the principal cell surface receptor for hyaluronate. Cell. 1990 Jun 29;61(7):1303–1313. doi: 10.1016/0092-8674(90)90694-a. [DOI] [PubMed] [Google Scholar]
  3. Badley J. E., Bishop G. A., St John T., Frelinger J. A. A simple, rapid method for the purification of poly A+ RNA. Biotechniques. 1988 Feb;6(2):114–116. [PubMed] [Google Scholar]
  4. Belitsos P. C., Hildreth J. E., August J. T. Homotypic cell aggregation induced by anti-CD44(Pgp-1) monoclonal antibodies and related to CD44(Pgp-1) expression. J Immunol. 1990 Mar 1;144(5):1661–1670. [PubMed] [Google Scholar]
  5. Bordier C. Phase separation of integral membrane proteins in Triton X-114 solution. J Biol Chem. 1981 Feb 25;256(4):1604–1607. [PubMed] [Google Scholar]
  6. Bourdon M. A., Krusius T., Campbell S., Schwartz N. B., Ruoslahti E. Identification and synthesis of a recognition signal for the attachment of glycosaminoglycans to proteins. Proc Natl Acad Sci U S A. 1987 May;84(10):3194–3198. doi: 10.1073/pnas.84.10.3194. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Burridge K., Fath K., Kelly T., Nuckolls G., Turner C. Focal adhesions: transmembrane junctions between the extracellular matrix and the cytoskeleton. Annu Rev Cell Biol. 1988;4:487–525. doi: 10.1146/annurev.cb.04.110188.002415. [DOI] [PubMed] [Google Scholar]
  8. Carter W. G., Kaur P., Gil S. G., Gahr P. J., Wayner E. A. Distinct functions for integrins alpha 3 beta 1 in focal adhesions and alpha 6 beta 4/bullous pemphigoid antigen in a new stable anchoring contact (SAC) of keratinocytes: relation to hemidesmosomes. J Cell Biol. 1990 Dec;111(6 Pt 2):3141–3154. doi: 10.1083/jcb.111.6.3141. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Carter W. G. Transformation-dependent alterations is glycoproteins of extracellular matrix of human fibroblasts. Characterization of GP250 and the collagen-like GP140. J Biol Chem. 1982 Nov 25;257(22):13805–13815. [PubMed] [Google Scholar]
  10. Carter W. G., Wayner E. A., Bouchard T. S., Kaur P. The role of integrins alpha 2 beta 1 and alpha 3 beta 1 in cell-cell and cell-substrate adhesion of human epidermal cells. J Cell Biol. 1990 Apr;110(4):1387–1404. doi: 10.1083/jcb.110.4.1387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Carter W. G., Wayner E. A. Characterization of the class III collagen receptor, a phosphorylated, transmembrane glycoprotein expressed in nucleated human cells. J Biol Chem. 1988 Mar 25;263(9):4193–4201. [PubMed] [Google Scholar]
  12. Cole G. J., Schubert D., Glaser L. Cell-substratum adhesion in chick neural retina depends upon protein-heparan sulfate interactions. J Cell Biol. 1985 Apr;100(4):1192–1199. doi: 10.1083/jcb.100.4.1192. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Dabelsteen E., Holbrook K., Clausen H., Hakomori S. Cell surface carbohydrate changes during embryonic and fetal skin development. J Invest Dermatol. 1986 Jul;87(1):81–85. doi: 10.1111/1523-1747.ep12523582. [DOI] [PubMed] [Google Scholar]
  14. Dalchau R., Kirkley J., Fabre J. W. Monoclonal antibody to a human brain-granulocyte-T lymphocyte antigen probably homologous to the W 3/13 antigen of the rat. Eur J Immunol. 1980 Oct;10(10):745–749. doi: 10.1002/eji.1830101004. [DOI] [PubMed] [Google Scholar]
  15. David G., Van den Berghe H. Heparan sulfate-chondroitin sulfate hybrid proteoglycan of the cell surface and basement membrane of mouse mammary epithelial cells. J Biol Chem. 1985 Sep 15;260(20):11067–11074. [PubMed] [Google Scholar]
  16. Ennis P. D., Zemmour J., Salter R. D., Parham P. Rapid cloning of HLA-A,B cDNA by using the polymerase chain reaction: frequency and nature of errors produced in amplification. Proc Natl Acad Sci U S A. 1990 Apr;87(7):2833–2837. doi: 10.1073/pnas.87.7.2833. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Flanagan B. F., Dalchau R., Allen A. K., Daar A. S., Fabre J. W. Chemical composition and tissue distribution of the human CDw44 glycoprotein. Immunology. 1989 Jun;67(2):167–175. [PMC free article] [PubMed] [Google Scholar]
  18. Gallatin W. M., Wayner E. A., Hoffman P. A., St John T., Butcher E. C., Carter W. G. Structural homology between lymphocyte receptors for high endothelium and class III extracellular matrix receptor. Proc Natl Acad Sci U S A. 1989 Jun;86(12):4654–4658. doi: 10.1073/pnas.86.12.4654. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Goldstein L. A., Zhou D. F., Picker L. J., Minty C. N., Bargatze R. F., Ding J. F., Butcher E. C. A human lymphocyte homing receptor, the hermes antigen, is related to cartilage proteoglycan core and link proteins. Cell. 1989 Mar 24;56(6):1063–1072. doi: 10.1016/0092-8674(89)90639-9. [DOI] [PubMed] [Google Scholar]
  20. Haynes B. F., Harden E. A., Telen M. J., Hemler M. E., Strominger J. L., Palker T. J., Scearce R. M., Eisenbarth G. S. Differentiation of human T lymphocytes. I. Acquisition of a novel human cell surface protein (p80) during normal intrathymic T cell maturation. J Immunol. 1983 Sep;131(3):1195–1200. [PubMed] [Google Scholar]
  21. Haynes B. F., Telen M. J., Hale L. P., Denning S. M. CD44--a molecule involved in leukocyte adherence and T-cell activation. Immunol Today. 1989 Dec;10(12):423–428. doi: 10.1016/0167-5699(89)90040-6. [DOI] [PubMed] [Google Scholar]
  22. Huet S., Groux H., Caillou B., Valentin H., Prieur A. M., Bernard A. CD44 contributes to T cell activation. J Immunol. 1989 Aug 1;143(3):798–801. [PubMed] [Google Scholar]
  23. Idzerda R. L., Carter W. G., Nottenburg C., Wayner E. A., Gallatin W. M., St John T. Isolation and DNA sequence of a cDNA clone encoding a lymphocyte adhesion receptor for high endothelium. Proc Natl Acad Sci U S A. 1989 Jun;86(12):4659–4663. doi: 10.1073/pnas.86.12.4659. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Isacke C. M., Sauvage C. A., Hyman R., Lesley J., Schulte R., Trowbridge I. S. Identification and characterization of the human Pgp-1 glycoprotein. Immunogenetics. 1986;23(5):326–332. doi: 10.1007/BF00398797. [DOI] [PubMed] [Google Scholar]
  25. Izzard C. S., Lochner L. R. Cell-to-substrate contacts in living fibroblasts: an interference reflexion study with an evaluation of the technique. J Cell Sci. 1976 Jun;21(1):129–159. doi: 10.1242/jcs.21.1.129. [DOI] [PubMed] [Google Scholar]
  26. Jalkanen S., Bargatze R. F., de los Toyos J., Butcher E. C. Lymphocyte recognition of high endothelium: antibodies to distinct epitopes of an 85-95-kD glycoprotein antigen differentially inhibit lymphocyte binding to lymph node, mucosal, or synovial endothelial cells. J Cell Biol. 1987 Aug;105(2):983–990. doi: 10.1083/jcb.105.2.983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Jalkanen S., Jalkanen M., Bargatze R., Tammi M., Butcher E. C. Biochemical properties of glycoproteins involved in lymphocyte recognition of high endothelial venules in man. J Immunol. 1988 Sep 1;141(5):1615–1623. [PubMed] [Google Scholar]
  28. Kalomiris E. L., Bourguignon L. Y. Mouse T lymphoma cells contain a transmembrane glycoprotein (GP85) that binds ankyrin. J Cell Biol. 1988 Feb;106(2):319–327. doi: 10.1083/jcb.106.2.319. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. King P. D., Batchelor A. H., Lawlor P., Katz D. R. The role of CD44, CD45, CD45RO, CD46 and CD55 as potential anti-adhesion molecules involved in the binding of human tonsillar T cells to phorbol 12-myristate 13-acetate-differentiated U-937 cells. Eur J Immunol. 1990 Feb;20(2):363–368. doi: 10.1002/eji.1830200220. [DOI] [PubMed] [Google Scholar]
  30. Koda J. E., Bernfield M. Heparan sulfate proteoglycans from mouse mammary epithelial cells. Basal extracellular proteoglycan binds specifically to native type I collagen fibrils. J Biol Chem. 1984 Oct 10;259(19):11763–11770. [PubMed] [Google Scholar]
  31. Laterra J., Silbert J. E., Culp L. A. Cell surface heparan sulfate mediates some adhesive responses to glycosaminoglycan-binding matrices, including fibronectin. J Cell Biol. 1983 Jan;96(1):112–123. doi: 10.1083/jcb.96.1.112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. LeBaron R. G., Esko J. D., Woods A., Johansson S., Hök M. Adhesion of glycosaminoglycan-deficient chinese hamster ovary cell mutants to fibronectin substrata. J Cell Biol. 1988 Mar;106(3):945–952. doi: 10.1083/jcb.106.3.945. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Lesley J., Schulte R., Hyman R. Binding of hyaluronic acid to lymphoid cell lines is inhibited by monoclonal antibodies against Pgp-1. Exp Cell Res. 1990 Apr;187(2):224–233. doi: 10.1016/0014-4827(90)90085-o. [DOI] [PubMed] [Google Scholar]
  34. Letarte M., Iturbe S., Quackenbush E. J. A glycoprotein of molecular weight 85,000 on human cells of B-lineage: detection with a family of monoclonal antibodies. Mol Immunol. 1985 Feb;22(2):113–124. doi: 10.1016/s0161-5890(85)80005-5. [DOI] [PubMed] [Google Scholar]
  35. Mali M., Jaakkola P., Arvilommi A. M., Jalkanen M. Sequence of human syndecan indicates a novel gene family of integral membrane proteoglycans. J Biol Chem. 1990 Apr 25;265(12):6884–6889. [PubMed] [Google Scholar]
  36. Mimms L. T., Zampighi G., Nozaki Y., Tanford C., Reynolds J. A. Phospholipid vesicle formation and transmembrane protein incorporation using octyl glucoside. Biochemistry. 1981 Feb 17;20(4):833–840. doi: 10.1021/bi00507a028. [DOI] [PubMed] [Google Scholar]
  37. Miyake K., Medina K. L., Hayashi S., Ono S., Hamaoka T., Kincade P. W. Monoclonal antibodies to Pgp-1/CD44 block lympho-hemopoiesis in long-term bone marrow cultures. J Exp Med. 1990 Feb 1;171(2):477–488. doi: 10.1084/jem.171.2.477. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Miyake K., Underhill C. B., Lesley J., Kincade P. W. Hyaluronate can function as a cell adhesion molecule and CD44 participates in hyaluronate recognition. J Exp Med. 1990 Jul 1;172(1):69–75. doi: 10.1084/jem.172.1.69. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Neame P. J., Christner J. E., Baker J. R. Cartilage proteoglycan aggregates. The link protein and proteoglycan amino-terminal globular domains have similar structures. J Biol Chem. 1987 Dec 25;262(36):17768–17778. [PubMed] [Google Scholar]
  40. Neyfakh A. A., Jr, Tint I. S., Svitkina T. M., Bershadsky A. D., Gelfand V. I. Visualization of cellular focal contacts using a monoclonal antibody to 80 kD serum protein adsorbed on the substratum. Exp Cell Res. 1983 Dec;149(2):387–396. doi: 10.1016/0014-4827(83)90351-8. [DOI] [PubMed] [Google Scholar]
  41. Nichols E. J., Fenderson B. A., Carter W. G., Hakomori S. Domain-specific distribution of carbohydrates in human fibronectins and the transformation-dependent translocation of branched type 2 chain defined by monoclonal antibody C6. J Biol Chem. 1986 Aug 25;261(24):11295–11301. [PubMed] [Google Scholar]
  42. Omary M. B., Trowbridge I. S., Letarte M., Kagnoff M. F., Isacke C. M. Structural heterogeneity of human Pgp-1 and its relationship with p85. Immunogenetics. 1988;27(6):460–464. doi: 10.1007/BF00364434. [DOI] [PubMed] [Google Scholar]
  43. Pals S. T., Hogervorst F., Keizer G. D., Thepen T., Horst E., Figdor C. C. Identification of a widely distributed 90-kDa glycoprotein that is homologous to the Hermes-1 human lymphocyte homing receptor. J Immunol. 1989 Aug 1;143(3):851–857. [PubMed] [Google Scholar]
  44. Parikh I., March S., Cuatercasas P. Topics in the methodology of substitution reactions with agarose. Methods Enzymol. 1974;34:77–102. doi: 10.1016/s0076-6879(74)34009-8. [DOI] [PubMed] [Google Scholar]
  45. Paulson J. C. Glycoproteins: what are the sugar chains for? Trends Biochem Sci. 1989 Jul;14(7):272–276. doi: 10.1016/0968-0004(89)90062-5. [DOI] [PubMed] [Google Scholar]
  46. Picker L. J., De los Toyos J., Telen M. J., Haynes B. F., Butcher E. C. Monoclonal antibodies against the CD44 [In(Lu)-related p80], and Pgp-1 antigens in man recognize the Hermes class of lymphocyte homing receptors. J Immunol. 1989 Mar 15;142(6):2046–2051. [PubMed] [Google Scholar]
  47. Pytela R., Pierschbacher M. D., Ruoslahti E. Identification and isolation of a 140 kd cell surface glycoprotein with properties expected of a fibronectin receptor. Cell. 1985 Jan;40(1):191–198. doi: 10.1016/0092-8674(85)90322-8. [DOI] [PubMed] [Google Scholar]
  48. Rice R. H., Green H. Presence in human epidermal cells of a soluble protein precursor of the cross-linked envelope: activation of the cross-linking by calcium ions. Cell. 1979 Nov;18(3):681–694. doi: 10.1016/0092-8674(79)90123-5. [DOI] [PubMed] [Google Scholar]
  49. Roman J., LaChance R. M., Broekelmann T. J., Kennedy C. J., Wayner E. A., Carter W. G., McDonald J. A. The fibronectin receptor is organized by extracellular matrix fibronectin: implications for oncogenic transformation and for cell recognition of fibronectin matrices. J Cell Biol. 1989 Jun;108(6):2529–2543. doi: 10.1083/jcb.108.6.2529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Ruoslahti E. Structure and biology of proteoglycans. Annu Rev Cell Biol. 1988;4:229–255. doi: 10.1146/annurev.cb.04.110188.001305. [DOI] [PubMed] [Google Scholar]
  51. Sanderson R. D., Bernfield M. Molecular polymorphism of a cell surface proteoglycan: distinct structures on simple and stratified epithelia. Proc Natl Acad Sci U S A. 1988 Dec;85(24):9562–9566. doi: 10.1073/pnas.85.24.9562. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Shimizu Y., Van Seventer G. A., Siraganian R., Wahl L., Shaw S. Dual role of the CD44 molecule in T cell adhesion and activation. J Immunol. 1989 Oct 15;143(8):2457–2463. [PubMed] [Google Scholar]
  54. Shively J. E., Conrad H. E. Formation of anhydrosugars in the chemical depolymerization of heparin. Biochemistry. 1976 Sep 7;15(18):3932–3942. doi: 10.1021/bi00663a005. [DOI] [PubMed] [Google Scholar]
  55. St John T., Meyer J., Idzerda R., Gallatin W. M. Expression of CD44 confers a new adhesive phenotype on transfected cells. Cell. 1990 Jan 12;60(1):45–52. doi: 10.1016/0092-8674(90)90714-p. [DOI] [PubMed] [Google Scholar]
  56. Stamenkovic I., Amiot M., Pesando J. M., Seed B. A lymphocyte molecule implicated in lymph node homing is a member of the cartilage link protein family. Cell. 1989 Mar 24;56(6):1057–1062. doi: 10.1016/0092-8674(89)90638-7. [DOI] [PubMed] [Google Scholar]
  57. Tautz D., Renz M. An optimized freeze-squeeze method for the recovery of DNA fragments from agarose gels. Anal Biochem. 1983 Jul 1;132(1):14–19. doi: 10.1016/0003-2697(83)90419-0. [DOI] [PubMed] [Google Scholar]
  58. Tomita M., Furthmayr H., Marchesi V. T. Primary structure of human erythrocyte glycophorin A. Isolation and characterization of peptides and complete amino acid sequence. Biochemistry. 1978 Oct 31;17(22):4756–4770. doi: 10.1021/bi00615a025. [DOI] [PubMed] [Google Scholar]
  59. Wayner E. A., Carter W. G. Identification of multiple cell adhesion receptors for collagen and fibronectin in human fibrosarcoma cells possessing unique alpha and common beta subunits. J Cell Biol. 1987 Oct;105(4):1873–1884. doi: 10.1083/jcb.105.4.1873. [DOI] [PMC free article] [PubMed] [Google Scholar]
  60. Wayner E. A., Carter W. G., Piotrowicz R. S., Kunicki T. J. The function of multiple extracellular matrix receptors in mediating cell adhesion to extracellular matrix: preparation of monoclonal antibodies to the fibronectin receptor that specifically inhibit cell adhesion to fibronectin and react with platelet glycoproteins Ic-IIa. J Cell Biol. 1988 Nov;107(5):1881–1891. doi: 10.1083/jcb.107.5.1881. [DOI] [PMC free article] [PubMed] [Google Scholar]
  61. Winship P. R. An improved method for directly sequencing PCR amplified material using dimethyl sulphoxide. Nucleic Acids Res. 1989 Feb 11;17(3):1266–1266. doi: 10.1093/nar/17.3.1266. [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. Woods A., Couchman J. R., Hök M. Heparan sulfate proteoglycans of rat embryo fibroblasts. A hydrophobic form may link cytoskeleton and matrix components. J Biol Chem. 1985 Sep 5;260(19):10872–10879. [PubMed] [Google Scholar]
  63. Woods A., Hök M., Kjellén L., Smith C. G., Rees D. A. Relationship of heparan sulfate proteoglycans to the cytoskeleton and extracellular matrix of cultured fibroblasts. J Cell Biol. 1984 Nov;99(5):1743–1753. doi: 10.1083/jcb.99.5.1743. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES