PROW: CD26

PROW and IWHLDA present the GUIDE on:
CD26
Author: Martin Hegen
Reviewer: Tamas Oravecz
[GUIDE BAR]

ALTERNATE NAMES FOR CD26

EC 3.4.14.5
adenosine deaminase-binding protein, ADA-binding protein
dipeptidylpeptidase IV, DPP IV ectoenzyme

MAJOR LINKS FOR CD26

NCBI LocusLink Record: 1803
Mendelian Inheritance in Man (OMIM): 102720
SwissProt annotated protein record: P27487

FUNCTION BIOCHEMICAL ACTIVITY OF CD26

Exopeptidase: cleaves off N-terminal X-Pro or X-Ala dipeptides from polypeptides (dipeptidyl peptidase IV activity)

CELLULAR FUNCTION OF CD26

Costimulatory molecule in T cell activation

DISEASE RELEVANCE OF CD26 AND FUNCTION OF CD26 IN INTACT ANIMAL

Associated marker of autoimmune diseases, adenosine deaminase-deficiency and HIV pathogenesis

STRUCTURE MOLECULAR FAMILY FOR CD26

Families in which CD26 is a member
- CD26-->peptidase S9B-->prolyl oligopeptidase-->serine-type peptidase-->peptidases classified by active site-->peptidases
- CD26-->ectoenzyme

MOLECULAR STRUCTURE OF CD26

Single chain type II transmembrane molecule (766 amino acids)
3 regions in extracellular region; membrane-proximal glycosylated region starting with a 20 amino acid flexible stalk region; cysteine-rich region; 260 amino acid C-terminal region containing dipeptidyl peptidase IV activity
6 amino acid cytoplasmic region
22 residue hydrophobic transmembrane region

MOLECULAR MASS OF CD26

CELL TYPE	MW UNREDUCED	MW REDUCED	Comment
Activated T cells	120, 110 kDa	110 kDa

POST-TRANSCRIPTIONAL MODIFICATION OF CD26

No alternate splicing, all 26 exons are translated
9 potential glycosylation sites
Different glycosylated forms are detected by immunoprecipitation with different CD26 mAbs

POST-TRANSLATIONAL MODIFICATION OF CD26 - No information

MOLECULAR INTERACTIONS PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD26

MOLECULE	COMMENT
SP-1	For transcription regulation see references 8, 9
AP2	For transcription regulation see references 8, 9
c-myb	For transcription regulation see references 8, 9
c-myc	For transcription regulation see references 8, 9
Butyrate-responsive element (BRE)	For transcription regulation see references 8, 9
HNF-1	For transcription regulation see references 8, 9
NFkB	For transcription regulation see references 8, 9

SUBSTRATES FOR CD26

Oligopeptides containing proline or alanine at the penultimate position
No natural substrates are identified yet

ENZYMES WHICH MODIFY CD26 - No information

LIGANDS FOR CD26 AND MOLECULES ASSOCIATED WITH CD26

MOLECULE	COMMENT
Adenosine-deaminase	Ref 10
Collagen	Ref 11
CD45	Ref 12

EXPRESSION MAIN CELLULAR EXPRESSION OF CD26

Mature thymocytes
Activated T-cells
B-cells
NK cells
Macrophages
By immunohistology: Renal proximal tubular epithelial cells, small intestinal epithelium, biliary canaliculae, and splenic sinus lining cells

AUTHOR'S ADDITIONAL INSIGHTS ON CD26 - No information

REAGENTS CD26-SPECIFIC MABS NEWLY ASSIGNED AT SIXTH INTERNATIONAL WORKSHOP

NAME(Workshop IDs)	SOURCE or REFERENCE	COMMENT
202.36	Vilella
EF5/A3	Kaehne
EF6/B10	Kaehne/Taeger
L272	Warner
BA5	van Agthoven
2A6	Poppema
22C3	van Lier / Voorn

SELECTION OF OTHER CD26-SPECIFIC REFERENCE MAB

NAME(Workshop IDs)	SOURCE or REFERENCE	COMMENT
4EL1C7	Ref 4
TII19-4-7	Ref 4
134-2C2	Ref 4
TS145

SELECTED REFERENCES ON CD26

REVIEWS

1. Morimoto, C. and Schlossman, S.F. Immunologist, 2, 4 (1994).

2. Fleischer B CD26: a surface protease involved in T-cell activation. Immunol Today 1994 15:180 PubMed

3. Yaron A,Naider F Proline-dependent structural and biological properties of peptides and proteins. Crit Rev Biochem Mol Biol 1993 28:31 PubMed

PRIMARY CITATIONS

4. Stein, H., Schwarting, R. and Niedobitek, G. In Leucocyte typing IV. (ed. W. Knapp et al.)p.412. Oxford University Press, Oxford. (1989).

5. Hegen M,Niedobitek G,Klein CE,Stein H,Fleischer B The T cell triggering molecule Tp103 is associated with dipeptidyl aminopeptidase IV activity. J Immunol 1990 144:2908 PubMed

6. Tanaka T,Camerini D,Seed B,Torimoto Y,Dang NH,Kameoka J,Dahlberg HN,Schlossman SF,Morimoto C Cloning and functional expression of the T cell activation antigen CD26. J Immunol 1992 149:481 PubMed

7. Hegen M,Camerini D,Fleischer B Function of dipeptidyl peptidase IV (CD26, Tp103) in transfected human T cells. Cell Immunol 1993 146:249 PubMed

8. Abbott CA,Baker E,Sutherland GR,McCaughan GW Genomic organization, exact localization, and tissue expression of the human CD26 (dipeptidyl peptidase IV) gene. Immunogenetics 1994 40:331 PubMed

9. Bohm SK,Gum JR Jr,Erickson RH,Hicks JW,Kim YS Human dipeptidyl peptidase IV gene promoter: tissue-specific regulation from a TATA-less GC-rich sequence characteristic of a housekeeping gene promoter. Biochem J 1995 311:835 PubMed

10. Kameoka J,Tanaka T,Nojima Y,Schlossman SF,Morimoto C Direct association of adenosine deaminase with a T cell activation antigen, CD26. Science 1993 261:466 PubMed

11. Bauvois B A collagen-binding glycoprotein on the surface of mouse fibroblasts is identified as dipeptidyl peptidase IV. Biochem J 1988 252:723 PubMed

12. Torimoto Y,Dang NH,Vivier E,Tanaka T,Schlossman SF,Morimoto C Coassociation of CD26 (dipeptidyl peptidase IV) with CD45 on the surface of human T lymphocytes. J Immunol 1991 147:2514 PubMed

13. Oravecz T,Roderiquez G,Koffi J,Wang J,Ditto M,Bou-Habib DC,Lusso P,Norcross MA CD26 expression correlates with entry, replication and cytopathicity of monocytotropic HIV-1 strains in a T-cell line. Nat Med 1995 1:919 PubMed

14. Dong RP,Kameoka J,Hegen M,Tanaka T,Xu Y,Schlossman SF,Morimoto C Characterization of adenosine deaminase binding to human CD26 on T cells and its biologic role in immune response. J Immunol 1996 156:1349 PubMed

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Modified 10/14/99 mpr@mail.nih.gov