Transmembrane collagen XVII, an epithelial adhesion protein, is shed from the cell surface by ADAMs

Abstract

Collagen XVII, a type II transmembrane protein and epithelial adhesion molecule, can be proteolytically shed from the cell surface to generate a soluble collagen. Here we investigated the release of the ectodomain and identi®ed the enzymes involved. After surface biotinylation of keratinocytes, the ectodomain was detectable in the medium within minutes and remained stable for >48 h. Shedding was enhanced by phorbol esters and inhibited by metalloprotease inhibitors, including hydroxamates and TIMP-3, but not by inhibitors of other protease classes or by TIMP-2. This pro®le implicated MMPs or ADAMs as candidate sheddases. MMP-2, MMP-9 and MT1-MMP were excluded, but TACE, ADAM-10 and ADAM-9 were shown to be expressed in keratinocytes and to be actively involved. Transfection with cDNAs for the three ADAMs resulted in increased shedding and, vice versa, in TACE-de®cient cells shedding was signi®cantly reduced, indicating that transmembrane collagen XVII represents a novel class of substrates for ADAMs. Functionally, release of the ectodomain of collagen XVII from the cell surface was associated with altered keratinocyte motility in vitro.

Gelatinase-mediated migration and invasion of cancer cells

“…The CTT peptide has also been used to modify the natural tropism of adenovirus for a therapeutic gene delivery in a rabbit restenosis model (Turunen et al, 2002). In addition, CTT peptide has been used to localize gelatinase activity in tissue samples using in situ zymography (Pirilä et al, 2001), and to evaluate the contribution of gelatinases in various biological processes including vasoconstriction, epithelial-mesenchymal transition and hepatitis (Cheng and Lovett, 2003;Fernandez-Patron et al, 2000;Franzke et al, 2002).…”

Collagenous Transmembrane Proteins: Recent Insights into Biology and Pathology*

“…pig, dog, mouse, rat, or chicken, do not have a furin consensus sequence in the NC16A domain, and at least murine collagen XVII and a human deletion mutant lacking the furin site are efficiently processed nonetheless. Collagen XVII is not directly cleaved by furin convertases but rather by proteinases of the ADAM family (26,27), which, in turn, are activated by furin. It remains to be seen whether furin also can activate sheddases other than ADAMs.…”

“…This is supported by the finding that inhibition of collagen XVII processing preserved hemidesmosomal attachment in cultured keratinocytes (32). In the meantime it has become obvious that cell adhesion and motility involve a number of receptors and ligands depending on the spatial and temporal biological context (4) and that these processes are quite complex (24,27,33,34).…”

Autocrine Extracellular Signal-regulated Kinase (ERK) Activation in Normal Human Keratinocytes: Metalloproteinase-mediated Release of Amphiregulin Triggers Signaling from ErbB1 to ERK

“…The MPs can be subdivided into the matrix metalloproteinases (MMPs) and the ADAMs. Although many MMPs are released into the extracellular space, they are still candidates for AR cleavage because certain MMPs (including tolloid, tolloid-like-1, MMP-2, and MMP-9) are known to bind to the surface of keratinocytes (Sternlicht and Werb, 2001;Franzke et al, 2002;Rattenholl et al, 2002;Veitch et al, 2003), and MT1-MMP (MMP-14) is membrane anchored. In resting adult skin, most MMPs are not constitutively expressed in keratinocytes, with the exception of MMP-7 (matrilysin) in eccrine sweat gland epithelium, MMP-2 (gelatinase A) in occasional basal keratinocytes, MMP-19, tolloid, and tolloid-like 1.…”