Components of the nuclear signaling cascade that regulate collagenase gene expression in response to integrin-derived signals.

Abstract

Abstract. We have shown previously that the expression of collagenase is upregulated in rabbit synovial fibroblasts cultured on a substrate of antibody to the o~5 chain of the et5131 integrin fibronectin receptor or on the 120-kD cellbinding chymotryptic fragment of plasma fibronectin, but remains at basal levels in cells plated on intact plasma fibronectin. We now have identified some of the components of a signaling pathway that couples the fibronectin receptor to the induction of collagenase transcription. We studied the control of collagenase gene expression in cells adhering to the 120-kD fragment of fibronectin, to antifibronectin receptor antibody, or to plasma fibronectin by transiently introducing promoter-reporter constructs into rabbit synovial fibroblasts before plating cells on these matrices. The constructs contained segments of the human collagenase promoter regulating transcription of chloramphenicol acyl transferase. Expression of constructs containing the -1200/-42-bp segment or the -139/-42-bp segment of the collagenase promoter inserted upstream from the reporter gene was induced to similar extents in cells plated on the 120-kD fragment of fibronectin or on anti-fibronectin receptor antibody, relative to that in fibroblasts plated on fibronectin. The expression of the construct containing the -66/-42-bp segment of the promoter was not regulated and was similar to that of the parent pBLCAT2 plasmid, suggesting that the -139/-67 region of the collagenase promoter, which contains PEA3-and APl-binding sites, regulates the transcription of collagenase caused by integrin-derived signals. Expression of a reporter construct containing only the PEA3 and AP1 sites in the collagenase promoter (-90/ -67) also increased in cells plated on the 120-kD fragment of fibronectin or on anti-fibronectin receptor antibody, relative to that in cells plated on fibronectin. Mutations in either the AP1 or PEA3 site of this minimal promoter abrogated its activity in cells plated on these inductive ligands. Expression of c-fos mRNA increased within 1 h of plating cells on the 120-kD fibronectin fragment or on anti-fibronectin receptor antibody, relative to that in cells plated on fibronectin, c-Fos protein accumulated in the nuclei of fibroblasts within 10 min of plating on the 120-kD fibronectin fragment. The increase in c-Fos was required for the increase in collagenase in cells plated on the 120-kD fibronectin fragment: incubation of cells with antisense, but not sense, c-los oligonucleotides diminished both basal and induced expression of the -139/ -42 collagenase promoter-reporter construct and decreased expression of the endogenous collagenase gene. Therefore, one of the pathways that transduce signals activated by the a5131 integrin fibronectin receptor propagates its response through promoters that contain AP1-and PEA3-responsive DNA sequences.

Integrin-mediated Adhesion of Endothelial Cells Induces JAK2 and STAT5A Activation: Role in the Control of c-fos Gene Expression

“…When G0-syncronized cells are plated on FN-coated dishes, early growth response genes, such as c-fos, c-myc, and c-jun, are rapidly induced (Dike and Farmer, 1988;Eierman et al, 1989;Tremble et al, 1995;Varner et al, 1995;Dike and Ingber, 1996). We show that STAT5A activated by integrinmediated adhesion binds to the SIE oligonucleotide sequence, a known STAT target region in the c-fos promoter (Zhong et al, 1994).…”

“…Integrin-induced signaling has been reported to affect gene expression (Dike and Farmer, 1988;Haskill et al, 1991;Chen et al, 1992;Rana et al, 1994;Schmidhauser et al, 1994;Fan et al, 1995;Tremble et al, 1995;Dike and Ingber, 1996). Among the early growth response genes encoding for transcriptional activators, adhesion-dependent induction of cfos gene transcription has been described in monocytes (Haskill et al, 1991), in endothelial cells (Dike and Ingber, 1996;Wary et al, 1996), and in fibroblasts (Tremble et al, 1995;Wary et al, 1996) and proposed as a mediator of cell cycle progression controlled by cell adhesion.The signaling pathways leading to integrin-dependent early growth response gene transcription are not completely defined. A role of activated Erk1/Erk2 MAP kinases in coupling integrins to gene expression has been recently proposed (Chen et al, 1992;Morino et al, 1995;Zhu and Assoian, 1995;Wary et al, 1996).…”

Regulation of a multigenic invasion programme by the transcription factor, AP-1: re-expression of a down-regulated gene, TSC-36, inhibits invasion

“…AP-1 activity and target gene expression are a ected by interaction of the cell with extracellular matrix proteins and alterations of the actin cytoskeleton, which can activate other transcription factors (Chang et al, 1998;Clarke et al, 1998;Lorenzi et al, 1999;Treisman et al, 1998;Tremble et al, 1995;Troussard et al, 1999;Westermarck and Kahari, 1999;Wisdom, 1999).…”

Disruption of Fibronectin Binding to the α5β1 Integrin Stimulates the Expression of Cyclin-dependent Kinases and DNA Synthesis through Activation of Extracellular Signal-regulated Kinase

“…Recent studies showed that integrins may also play an important role in the control of gene expression. Exposure of rabbit synovial fibroblasts to fibronectin fragments or anti-FN receptor antibody induces the expression of metalloproteinase, stromelysin, and a 92-kDa gelatinase (15)(16)(17)(18). Overexpression of ␣ 5 ␣ 1 in human colon carcinoma HT29 cells induces the transcription of growth arrest-specific gene 1 (GAS-1) and blocks the transcription of immediate early genes c-FOS, c-JUN, and JUN-B (19).…”