ADAM-TS5, ADAM-TS6, and ADAM-TS7, Novel Members of a New Family of Zinc Metalloproteases

Abstract

We report the primary structure of three novel, putative zinc metalloproteases designated ADAM-TS5, ADAM-TS6, and ADAM-TS7. All have a similar domain organization, comprising a preproregion, a reprolysintype catalytic domain, a disintegrin-like domain, a thrombospondin type-1 (TS) module, a cysteine-rich domain, a spacer domain without cysteine residues, and a COOH-terminal TS module. These genes are differentially regulated during mouse embryogenesis and in adult tissues, with Adamts5 highly expressed in the periimplantation period in embryo and trophoblast. These proteins are similar to four other cognate gene products, defining a distinct family of human reprolysin-like metalloproteases, the ADAM-TS family. The other members of the family are ADAM-TS1, an inflammation-induced gene, the procollagen I/II amino-propeptide processing enzyme (PCINP, ADAM-TS2), and proteins predicted by the KIAA0366 and KIAA0688 genes (ADAM-TS3 and ADAM-TS4). Individual ADAM-TS members differ in the number of COOH-terminal TS modules, and some have unique COOH-terminal domains. The ADAM-TS genes are dispersed in human and mouse genomes. Proteolysis of extracellular matrix (ECM)1 plays a critical role in establishing tissue architecture during development and in tissue degradation in diseases such as cancer, arthritis, Alzheimer's disease, and a variety of inflammatory conditions (1-3). The proteolytic enzymes responsible include members of diverse protease families and they may work in concert or in cascades to degrade or process molecules. Two groups of zinc metalloproteases in particular, ADAMs (a disintegrin and metalloprotease) (2-4) and MMPs (matrix metalloproteinases) (1), appear broadly relevant to extracellular proteolysis. These families include a large number of enzymes (over 20 gene products each) with demonstrated cleavage activity for matrix molecules as well as nonmatrix, bioactive molecules such as tumor necrosis factor-␣ (reviewed in Ref. 3). In other instances of extracellular proteolysis, such as cleavage of aggrecan at the Glu 373 -Ala 374 peptide bond (5) or the shedding of L-selectin from leukocytes (6), the responsible proteases have not yet been reported. Such activities may eventually be attributed to cognate proteases but they may well be due to one or more hitherto unknown enzymes. For these reasons, it is important to define the full repertoire of enzymes possessed by cells, their regulation, and their substrate preferences.ADAMs, also referred to as MDC (metalloprotease-disintegrins with cysteine-rich domains, 2) have catalytic domains with zinc-binding signatures and disintegrin domains that are very similar to the snake venom metalloproteinases (reviewed in Ref. 7); together, the ADAMs and snake venom metalloproteinases are referred to as reprolysins (7). Most ADAM members are quite similar in domain organization (2, 4, 7), bearing from amino to carboxyl termini, a signal peptide, a proregion, a zinc-metalloprotease catalytic domain with the typical reprolysin signature HEX 1 X 2 HX 3 X 1 GX 1 XHD (X i...

Characterization of ADAMTS-9 and ADAMTS-20 as a Distinct ADAMTS Subfamily Related to Caenorhabditis elegans GON-1

“…To extend the initially identified ADAMTS9 cDNA to the 5Ј-end, human chondrocyte, muscle, heart, or fetal brain mRNA (Marathon cDNA, Clontech, Palo Alto, CA) was used as the template for rapid amplification of cDNA ends as previously described (1). To confirm that the overlapping cDNA clones obtained represented a contiguous mRNA, the complete ORF was amplified by PCR.…”

“…cDNA Cloning and Sequence Analysis of ADAMTS9 and AD-AMTS20 -BLAST (Basic Local Alignment Search Tool) programs from the National Center for Biotechnology Information were used to search the data base of expressed sequence tags (dBEST), using the protein sequences of ADAMTS proteases previously discovered by us (1,18). To extend the initially identified ADAMTS9 cDNA to the 5Ј-end, human chondrocyte, muscle, heart, or fetal brain mRNA (Marathon cDNA, Clontech, Palo Alto, CA) was used as the template for rapid amplification of cDNA ends as previously described (1).…”

“…The ADAMTS (A disintegrin-like and metalloprotease (reprolysin type) with thrombospondin type I motif) family consists of secreted zinc metalloproteases with a precisely ordered modular organization that includes at least one thrombospondin type I repeat (TSR) 1 (1,2). Important functions have been established for several members of the family.…”

Binding of platelet glycoprotein Ibα to von Willebrand factor domain A1 stimulates the cleavage of the adjacent domain A2 by ADAMTS13

“…vWF is secreted into the blood by endothelial cells as unusually large multimers (2, 3) with especially high affinity for GPIb␣ (4). Unusually large multimers are converted into a series of smaller multimers by the metalloprotease ADAMTS13 (5), a member of the ''a disintegrin and metalloprotease with thrombospondin'' repeats family of proteases (6)(7)(8)(9)(10). ADAMTS13 cleaves the Tyr-1605-Met-1606 bond in the central domain, A2, of vWF (11,12) and thereby regulates vWF-dependent platelet adhesion.…”

Cleavage of von Willebrand Factor Requires the Spacer Domain of the Metalloprotease ADAMTS13

“…The VWF-cleaving protease was recently purified and identified as a new member of the ADAMTS family of metalloproteases (10,11), so named for the combination of a disintegrin-like and metalloprotease (reprolysin type), with thrombospondin type 1 motifs (12). The primary structure of the ADAMTS13 precursor was determined by cDNA cloning (13,14) and by positional cloning in families with inherited AD-AMTS13 deficiency (15).…”