Fibronectin, the major cell surface glycoprotein of fibroblasts, is absent from differentiated cartilage matrix and chondrocytes in situ. However, dissociation of embryonic chick sternal cartilage with collagenase and trypsin, followed by inoculation in vitro reinitiates fibronectin synthesis by chondrocytes. Immunofluorescence microscopy with antibodies prepared against plasma fibronectin (col...

Autophagy is a cellular process that executes the turnover of dysfunctional organelles and misfolded or abnormally aggregated proteins. Microtubule-associated protein MAP1S interacts with autophagy marker LC3 and positively regulates autophagy flux. LC3 binds with fibronectinmRNA and facilitates its translation. The synthesized fibronectin protein is exported to cell surface to initiate the ass...

Studies have established that cryoprecipitates of the plasma of tumor patients contain a biological activity enhancing morphological cell transformation (transformation-enhancing factor; TEF) in cultures of chicken embryo fibroblasts infected with temperature-sensitive mutants of Rous sarcoma virus. We report here that similar TEF activity is effected by defined fragments of human plasma fibron...

Fibronectin, a fibroblast surface protein, was purified from human and chicken plasma and extracts of cultured chicken fibroblasts with affinity chromatography on gelatin coupled to Sepharose particles. A fibronectin-like protein was also isolated from the plasma of Torpedo fish. The collagen binding properties of fibronectin were studied with several genetically distinct collagens. Heat denatu...

The ability of Streptococcus pyogenes lipoteichoic acid and palmitic acid to bind to purified human plasma fibronectin was investigated. Initial studies indicated that intact fibronectin formed soluble complexes with lipoteichoic acid, resulting in a change in the mobility of fibronectin in an electrical field. Fibronectin covalently linked to agarose beads bound radiolabeled lipoteichoic acid ...

Plasma fibronectin is a component of the fibrin clot, a provisional matrix that arrests bleeding but that can also obstruct flow in blood vessels. The goal of this study was to examine the influence of fibronectin on the formation, structural characteristics and composition of reconstituted fibrin clots. Fibrin clots were formed by adding thrombin to 1 mg/ml, 2 mg/ml or 4 mg/ml fibrinogen suppl...

IgA deposition in the glomerular mesangial matrix is a prerequisite for the diagnosis of IgA nephropathy, and circulating IgA-containing complex has been implicated in this process. Since fibronectin is known to be involved in the assembly of extracellular matrix, this study was conducted to investigate whether fibronectin and its fragments are present in sera of patients and are capable of bin...

The cellular source of fibronectin in the dental epitheliomesenchymal interface was studied in interspecies combinations of mouse and quail tissue. Species-specific fibronectin antibodies were produced by immunizing rabbits with purified mouse or chicken fibronectin and by absorbing both antisera with purified heterologous fibronectin and insoluble tissue extract. The absorbed antisera to mouse...

We have shown previously that the expression of collagenase is upregulated in rabbit synovial fibroblasts cultured on a substrate of antibody to the alpha 5 chain of the alpha 5 beta 1 integrin fibronectin receptor or on the 120-kD cell-binding chymotryptic fragment of plasma fibronectin, but remains at basal levels in cells plated on intact plasma fibronectin. We now have identified some of th...

In an initial report (Carbonetto, S. T., M. M. Gruver, and D. C. Turner (1982) Science 216: 897-899) we described the use of 2-hydroxyethylmethacrylate (HEMA) in preparing defined culture substrates for studying nerve fiber growth. In those studies fibronectin and collagen were conspicuous, among a variety of HEMA-embedded proteins, in supporting fiber growth of embryonic neurons from chick dor...