The 3D structure of rat DPPIV/CD26 as obtained by cryo-TEM and single particle analysis

Biochem Biophys Res Commun. 2003 Apr 25;304(1):73-7. doi: 10.1016/s0006-291x(03)00539-4.


We present the three-dimensional structure of rat DPPIV/CD26, as determined by cryo-TEM and single particle analysis at a resolution of approximately 14A. The reconstruction confirms that the protein exists as a dimer, as predicted earlier. Since there are structural analogies to the serine peptidase POP, docking calculations of the two structures were performed. Although the docking showed a similar spatial organization (catalytic domain, beta-propeller, distal opening, central cavity), the detailed comparison revealed clear discrepancies. The most marked difference is a second (lateral) opening in DPPIV/CD26, which would enable direct access to the catalytic site. We therefore assume that substrate selectivity and binding rate are most probably driven by different mechanisms in DPPIV/CD26 and POP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Catalytic Domain
  • Cryoelectron Microscopy / methods
  • Dimerization
  • Dipeptidyl Peptidase 4 / chemistry*
  • Dipeptidyl Peptidase 4 / metabolism
  • Image Processing, Computer-Assisted
  • Models, Molecular*
  • Prolyl Oligopeptidases
  • Rats
  • Serine Endopeptidases / chemistry
  • Serine Endopeptidases / metabolism


  • Dipeptidyl Peptidase 4
  • Serine Endopeptidases
  • Prolyl Oligopeptidases