title: The salivary lipocalin von Ebner's gland protein is a cysteine proteinase inhibitor.
abstract: The lipocalins make up a heterogeneous superfamily of proteins. Although showing almost no sequence homology, they share very similar secondary and tertiary structures. Their ability to bind hydrophobic ligands is well established, but the physiological function of most lipocalins remains unclear. The lipocalin from the human Von Ebner's Gland of the tongue (VEGh) contains three sequence motifs corresponding with the papain-binding domains of cystatins, a family of naturally occurring cysteine proteinase inhibitors. We found that VEGh inhibited papain activity to a similar extent as salivary cystatin S. Furthermore, synthetic peptides derived from VEGh and cystatin C, comprising these three motifs, inhibited papain, too. We conclude that VEGh is a physiological inhibitor of cysteine proteinases and therefore can play a role in the control of inflammatory processes in oral and ocular tissues.
authors.affiliation: Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, 1081 BT Amsterdam, The Netherlands. w.van_t_hof.obc.acta@med.vu.nl
authors.forename: W
authors.initials: W
authors.lastname: van't Hof
authors.forename: M F
authors.initials: MF
authors.lastname: Blankenvoorde
authors.forename: E C
authors.initials: EC
authors.lastname: Veerman
authors.forename: A V
authors.initials: AV
authors.lastname: Amerongen
mesh_terms: D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002852:Chromatography, Ion Exchange; D015853:Cysteine Proteinase Inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D054835:Lipocalin 1; D008969:Molecular Sequence Data; D012463:Saliva / Q000378:metabolism*; D012471:Salivary Proteins and Peptides / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D002352:Carrier Proteins; D015853:Cysteine Proteinase Inhibitors; C518443:LCN1 protein, human; D054835:Lipocalin 1; D012471:Salivary Proteins and Peptides