Regulated expression of an osteonectin variant in bovine aortic endothelial cells

Using a mouse SPARC (Secreted Protein, Acidic and Rich in Cysteine) cDNA clone as the probe, three clones were isolated from a cDNA library of bovine aortic endothelial cells (BAEC). Inserted sequences in them were identical with that of bovine bone osteonectin except for the deletion of the TGC codon encoding Cys-193. Northern blot analysis and metabolic radio-labeling of BAEC showed that gene expression and synthesis of the osteonectin variant is stimulated by transforming growth factor (TGF) beta, a basic fibroblast growth factor (FGF), or a naturally occurring splicing variant of hepatocyte growth factor (varHGF).