title: Role of a propeller loop in the quaternary structure and enzymatic activity of prolyl dipeptidases DPP-IV and DPP9.
abstract: The dipeptidyl peptidase (DPP) family members, including DPP-IV, DPP8, DPP9 and others, cleave the peptide bond after the penultimate proline residue and are drug target rich. The dimerization of DPP-IV is required for its activity. A propeller loop located at the dimer interface is highly conserved within the family. Here we carried out site-directed mutagenesis on the loop of DPPIV and identified several residues important for dimer formation and enzymatic activity. Interestingly, the corresponding residues on DPP9 have a different impact whereby the mutations decrease activity without changing dimerization. Thus the propeller loop seems to play a varying role in different DPPs.
authors: Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli 350, Taiwan, ROC.
authors: Hung-Kuan
authors: HK
authors: Tang
authors: Ku-Chuan
authors: KC
authors: Chen
authors: Gan-Guang
authors: GG
authors: Liou
authors: Shu-Chun
authors: SC
authors: Cheng
authors: Chia-Hui
authors: CH
authors: Chien
authors: Hsiang-Yun
authors: HY
authors: Tang
authors: Li-Hao
authors: LH
authors: Huang
authors: Hui-Ping
authors: HP
authors: Chang
authors: Chi-Yuan
authors: CY
authors: Chou
authors: Xin
authors: X
authors: Chen
mesh_terms: D000595:Amino Acid Sequence; D018819:Dipeptidyl Peptidase 4 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary
chemical_list: C471241:DPP9 protein, human; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; C042807:DPP4 protein, human; D018819:Dipeptidyl Peptidase 4