title: The substrate degradome of meprin metalloproteases reveals an unexpected proteolytic link between meprin β and ADAM10.
abstract: The in vivo roles of meprin metalloproteases in pathophysiological conditions remain elusive. Substrates define protease roles. Therefore, to identify natural substrates for human meprin α and β we employed TAILS (terminal amine isotopic labeling of substrates), a proteomics approach that enriches for N-terminal peptides of proteins and cleavage fragments. Of the 151 new extracellular substrates we identified, it was notable that ADAM10 (a disintegrin and metalloprotease domain-containing protein 10)-the constitutive α-secretase-is activated by meprin β through cleavage of the propeptide. To validate this cleavage event, we expressed recombinant proADAM10 and after preincubation with meprin β, this resulted in significantly elevated ADAM10 activity. Cellular expression in murine primary fibroblasts confirmed activation. Other novel substrates including extracellular matrix proteins, growth factors and inhibitors were validated by western analyses and enzyme activity assays with Edman sequencing confirming the exact cleavage sites identified by TAILS. Cleavages in vivo were confirmed by comparing wild-type and meprin(-/-) mice. Our finding of cystatin C, elafin and fetuin-A as substrates and natural inhibitors for meprins reveal new mechanisms in the regulation of protease activity important for understanding pathophysiological processes.
authors.affiliation: Institute of Biochemistry, Christian-Albrechts-University, 24118, Kiel, Germany.
authors.forename: Tamara
authors.initials: T
authors.lastname: Jefferson
authors.forename: Ulrich
authors.initials: U
authors.lastname: Auf dem Keller
authors.forename: Caroline
authors.initials: C
authors.lastname: Bellac
authors.forename: Verena V
authors.initials: VV
authors.lastname: Metz
authors.forename: Claudia
authors.initials: C
authors.lastname: Broder
authors.forename: Jana
authors.initials: J
authors.lastname: Hedrich
authors.forename: Anke
authors.initials: A
authors.lastname: Ohler
authors.forename: Wladislaw
authors.initials: W
authors.lastname: Maier
authors.forename: Viktor
authors.initials: V
authors.lastname: Magdolen
authors.forename: Erwin
authors.initials: E
authors.lastname: Sterchi
authors.forename: Judith S
authors.initials: JS
authors.lastname: Bond
authors.forename: Arumugam
authors.initials: A
authors.lastname: Jayakumar
authors.forename: Heiko
authors.initials: H
authors.lastname: Traupe
authors.forename: Athena
authors.initials: A
authors.lastname: Chalaris
authors.forename: Stefan
authors.initials: S
authors.lastname: Rose-John
authors.forename: Claus U
authors.initials: CU
authors.lastname: Pietrzik
authors.forename: Rolf
authors.initials: R
authors.lastname: Postina
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Overall
authors.forename: Christoph
authors.initials: C
authors.lastname: Becker-Pauly
mesh_terms: D051722:ADAM Proteins / Q000378:metabolism*; D000072197:ADAM10 Protein; D000595:Amino Acid Sequence; D053829:Amyloid Precursor Protein Secretases / Q000378:metabolism*; D000818:Animals; D018938:Caco-2 Cells; D002460:Cell Line; D055316:Cystatin C / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D053492:Elafin / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000378:metabolism*; D045726:Metalloproteases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D060749:alpha-2-HS-Glycoprotein / Q000378:metabolism
chemical_list: D055316:Cystatin C; D016207:Cytokines; D053492:Elafin; D016326:Extracellular Matrix Proteins; D008565:Membrane Proteins; D060749:alpha-2-HS-Glycoprotein; D053829:Amyloid Precursor Protein Secretases; D045726:Metalloproteases; D051722:ADAM Proteins; D008666:Metalloendopeptidases; C053833:meprin A; D000072197:ADAM10 Protein; C491236:ADAM10 protein, human