The tetra-aspartate motif in the activation peptide of human cationic trypsinogen is essential for autoactivation control but not for enteropeptidase recognition.

ABSTRACT: The activation peptide of vertebrate trypsinogens contains a highly conserved tetra-aspartate sequence (Asp(19-22) in humans) preceding the Lys-Ile scissile bond. A large body of research has defined the primary role of this acidic motif as a specific recognition site for enteropeptidase, the physiological activator of trypsinogen. In addition, the acidic stretch was shown to contribute to the suppression of autoactivation. In the present study, we determined the relative importance of these two activation peptide functions in human cationic trypsinogen. Individual Ala replacements of Asp(19-22) had minimal or no effect on trypsinogen activation catalyzed by human enteropeptidase. Strikingly, a tetra-Ala(19-22) trypsinogen mutant devoid of acidic residues in the activation peptide was stil

SUBMITTER: Nemoda Z 

PROVIDER: S-EPMC1420407 | biostudies-literature | 2005 Aug

REPOSITORIES: biostudies-literature