Mmp-20 and Klk4 cleavage site preferences for amelogenin sequences.

ABSTRACT: Mmp-20 and Klk4 are the two key enamel proteases. Can both enzymes process amelogenin to generate the major cleavage products that accumulate during the secretory stage of amelogenesis? We isolated Mmp-20 and Klk4 from developing pig teeth and used them to digest the tyrosine-rich amelogenin polypeptide (TRAP), the leucine-rich amelogenin protein (LRAP), and 5 fluorescence peptides. We characterized the digestion products by LC-MSMS, SDS-PAGE, and C18 RP-HPLC monitored with fluorescence and UV detectors. Mmp-20 cleaves amelogenin sequences after Pro(162), Ser(148), His(62), Ala(63), and Trp(45). These cleavages generate all of the major cleavage products that accumulate in porcine secretory-stage enamel: the 23-kDa, 20-kDa, 13-kDa, 11-kDa, and 6-kDa (TRAP) amelogenins. Mmp-20 cleaves LRAP

SUBMITTER: Nagano T 

PROVIDER: S-EPMC2751868 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature