1u8e is a 2 chain structure with sequence from Homo sapiens. This structure supersedes the now removed PDB entry 1to7. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
DPP4_HUMAN Cell surface glycoprotein receptor involved in the costimulatory signal essential for T-cell receptor (TCR)-mediated T-cell activation. Acts as a positive regulator of T-cell coactivation, by binding at least ADA, CAV1, IGF2R, and PTPRC. Its binding to CAV1 and CARD11 induces T-cell proliferation and NF-kappa-B activation in a T-cell receptor/CD3-dependent manner. Its interaction with ADA also regulates lymphocyte-epithelial cell adhesion. In association with FAP is involved in the pericellular proteolysis of the extracellular matrix (ECM), the migration and invasion of endothelial cells into the ECM. May be involved in the promotion of lymphatic endothelial cells adhesion, migration and tube formation. When overexpressed, enhanced cell proliferation, a process inhibited by GPC3. Acts also as a serine exopeptidase with a dipeptidyl peptidase activity that regulates various physiological processes by cleaving peptides in the circulation, including many chemokines, mitogenic growth factors, neuropeptides and peptide hormones. Removes N-terminal dipeptides sequentially from polypeptides having unsubstituted N-termini provided that the penultimate residue is proline.[1][2][3][4][5][6][7][8][9]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Human dipeptidyl peptidase IV (DPP-IV) is a ubiquitously expressed type II transmembrane serine protease. It cleaves the penultimate positioned prolyl bonds at the N terminus of physiologically important peptides such as the incretin hormones glucagon-like peptide 1 and glucose-dependent insulinotropic peptide. In this study, we have characterized different active site mutants. The Y547F mutant as well as the catalytic triad mutants S630A, D708A, and H740L showed less than 1% wild type activity. X-ray crystal structure analysis of the Y547F mutant revealed no overall changes compared with wild type apoDPP-IV, except the ablation of the hydroxyl group of Tyr(547) and a water molecule positioned in close proximity to Tyr(547). To elucidate further the reaction mechanism, we determined the crystal structure of DPP-IV in complex with diisopropyl fluorophosphate, mimicking the tetrahedral intermediate. The kinetic and structural findings of the tyrosine residue are discussed in relation to the catalytic mechanism of DPP-IV and to the inhibitory mechanism of the 2-cyanopyrrolidine class of potent DPP-IV inhibitors, proposing an explanation for the specificity of this class of inhibitors for the S9b family among serine proteases.
Tyrosine 547 constitutes an essential part of the catalytic mechanism of dipeptidyl peptidase IV.,Bjelke JR, Christensen J, Branner S, Wagtmann N, Olsen C, Kanstrup AB, Rasmussen HB J Biol Chem. 2004 Aug 13;279(33):34691-7. Epub 2004 Jun 2. PMID:15175333[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑Durinx C, Lambeir AM, Bosmans E, Falmagne JB, Berghmans R, Haemers A, Scharpe S, De Meester I. Molecular characterization of dipeptidyl peptidase activity in serum: soluble CD26/dipeptidyl peptidase IV is responsible for the release of X-Pro dipeptides. Eur J Biochem. 2000 Sep;267(17):5608-13. PMID:10951221
↑Davoodi J, Kelly J, Gendron NH, MacKenzie AE. The Simpson-Golabi-Behmel syndrome causative glypican-3, binds to and inhibits the dipeptidyl peptidase activity of CD26. Proteomics. 2007 Jun;7(13):2300-10. PMID:17549790 doi:10.1002/pmic.200600654
↑Abbott CA, McCaughan GW, Gorrell MD. Two highly conserved glutamic acid residues in the predicted beta propeller domain of dipeptidyl peptidase IV are required for its enzyme activity. FEBS Lett. 1999 Sep 24;458(3):278-84. PMID:10570924
↑Ikushima H, Munakata Y, Ishii T, Iwata S, Terashima M, Tanaka H, Schlossman SF, Morimoto C. Internalization of CD26 by mannose 6-phosphate/insulin-like growth factor II receptor contributes to T cell activation. Proc Natl Acad Sci U S A. 2000 Jul 18;97(15):8439-44. PMID:10900005
↑Gines S, Marino M, Mallol J, Canela EI, Morimoto C, Callebaut C, Hovanessian A, Casado V, Lluis C, Franco R. Regulation of epithelial and lymphocyte cell adhesion by adenosine deaminase-CD26 interaction. Biochem J. 2002 Jan 15;361(Pt 2):203-9. PMID:11772392
↑Aertgeerts K, Ye S, Shi L, Prasad SG, Witmer D, Chi E, Sang BC, Wijnands RA, Webb DR, Swanson RV. N-linked glycosylation of dipeptidyl peptidase IV (CD26): effects on enzyme activity, homodimer formation, and adenosine deaminase binding. Protein Sci. 2004 Jan;13(1):145-54. PMID:14691230 doi:10.1110/ps.03352504
↑Ghersi G, Zhao Q, Salamone M, Yeh Y, Zucker S, Chen WT. The protease complex consisting of dipeptidyl peptidase IV and seprase plays a role in the migration and invasion of human endothelial cells in collagenous matrices. Cancer Res. 2006 May 1;66(9):4652-61. PMID:16651416 doi:10.1158/0008-5472.CAN-05-1245
↑Ohnuma K, Uchiyama M, Yamochi T, Nishibashi K, Hosono O, Takahashi N, Kina S, Tanaka H, Lin X, Dang NH, Morimoto C. Caveolin-1 triggers T-cell activation via CD26 in association with CARMA1. J Biol Chem. 2007 Mar 30;282(13):10117-31. Epub 2007 Feb 6. PMID:17287217 doi:10.1074/jbc.M609157200
↑Shin JW, Jurisic G, Detmar M. Lymphatic-specific expression of dipeptidyl peptidase IV and its dual role in lymphatic endothelial function. Exp Cell Res. 2008 Oct 1;314(16):3048-56. doi: 10.1016/j.yexcr.2008.07.024. Epub , 2008 Aug 3. PMID:18708048 doi:10.1016/j.yexcr.2008.07.024
↑Bjelke JR, Christensen J, Branner S, Wagtmann N, Olsen C, Kanstrup AB, Rasmussen HB. Tyrosine 547 constitutes an essential part of the catalytic mechanism of dipeptidyl peptidase IV. J Biol Chem. 2004 Aug 13;279(33):34691-7. Epub 2004 Jun 2. PMID:15175333 doi:https://dx.doi.org/10.1074/jbc.M405400200
