Cell surface annexin II is a high affinity receptor for the alternatively spliced segment of tenascin-C.

Abstract

Abstract. We have investigated the binding of soluble tenascin-C (TN-C) to several cell lines using a radioligand binding assay. Specific binding was demonstrated to U-251MG human glioma cells and to a line of bovine aortic endothelial cells, but hamster fibroblasts showed no specific binding. Recombinant proteins corresponding to specific domains of TN-C were used to map the binding site(s) in TN-C. The alternatively spliced segment (TNfnA-D) inhibited the binding of native TN-C most strongly, and itself bound to glioma and endothelial cells. Scatchard analysis of TNfnA-D binding indicated 2-5 x 105 binding sites per cell, with an apparent 2 nM dissociation constant. The cell surface receptor for TNfnA-D was identified as a 35-kD protein on the basis of blot binding assays and affinity chromatography of membrane extracts on native TN-C and TNfnA-D columns. Protein sequencing indicated that this 35-kD receptor was annexin lI. Annexin 11 is well characterized as a cytoplasmic prorein, so it was surprising to find it as a presumably extraceLlular receptor for TN-C. To confirm that it was the 35-kD receptor, we obtained purified annexin lI and demonstrated its binding to TNfnA-D and TN-C at nM concentrations. Antibodies to annexin II prominently stained the external surface of live endothelial ceils and blocked the binding of TNfnA-D to the cells. Thus annexin II appears to be a receptor for the alternatively spliced segment of TN-C, and may mediate cellular responses to soluble TN-C in the extraceLlular matrix.

Expression and degeneration of tenascin-C in human lung cancers

“…With regard to the activity of the alternatively spliced domain of TN-C, two papers have appeared in the literature reporting an association with down-regulation of focal adhesion of cells (Murphy-Ullrich et al, 1991) and stimulation of corneal cell migration (Kaplony et al, 1991). Other studies using recombinant fragment of human TN-C have revealed that the alternatively Tenascin-C in lung cancer 101 spliced domain can bind to annexin II on human endothelial cells and promote cell migration (Chung and Erickson, 1994;Chung et al, 1996). These findings suggest that the larger TN-C molecules may be involved in detachment of cells from the stroma and in cell movement, thus affecting the malignant behaviour of tumour cells.…”

Annexin II binds progastrin and gastrin-like peptides, and mediates growth factor effects of autocrine and exogenous gastrins on colon cancer and intestinal epithelial cells

“…RBA of Tenascin-C for binding PG binding sites ANX II was identified as a receptor protein for tenascin-C (TN-C) (Chung and Erickson, 1994). A splice variant fragment of TN-C, TNfnA-D, had the highest binding affinity for ANX II (Chung and Erickson, 1994).…”

“…A splice variant fragment of TN-C, TNfnA-D, had the highest binding affinity for ANX II (Chung and Erickson, 1994). Annexin II binds progastrin P Singh et al Table 1.…”

“…ANX II has previously been described as a high-affinity receptor for the extracellular matrix protein TN-C (Chung and Erickson, 1994), and as a co-receptor on endothelial cells for tissue plasminogen activator, plasminogen and plasmin (Hajjar and Acharya, 2000). AIIt was identified as a receptor for plasmin-induced signaling in human peripheral monocytes, which involved the activation of nuclear factor (NF)-kB, JAK/ signal transducers and activators of transcription (STAT) and p38 mitogen-activated protein kinase (MAPK) signaling cascades, leading to a full-scale proinflammatory response (Laumonnier et al, 2006).…”

“…This may explain our findings of a significant increase in the crosslinking of gastrins to ANX II (B32-36 kDa) at slightly acidic pH (Figure 3b). The 36 kDa ANX II protein, bound to radio-labeled TNfnA-D, was generally seen as a doublet band in SDS-PAGE (Chung and Erickson, 1994). In freshly prepared membrane extracts, the authors frequently saw a single band of 36 kDa; two lower molecular weight bands appeared at later times (Chung and Erickson, 1994).…”