ADHESION-INDUCIBLE DNA-SYNTHESIS REGULATED BY TYROSINE PHOSPHORYLATION DEPHOSPHORYLATION

Non-malignant rat liver epithelial cell line BRL was reported to adher e to a substrate by fibronectin. DNA synthesis of these cells was indu ced by adhesion to a substrate by fibronectin, while DNA synthesis in non-adhered cells was not observed. These results indicated that DNA s ynthesis in BRL cells is inducible by the cell adhesion signaling. Adh esion-inducible DNA synthesis was strongly inhibited by Herbimycin A. In contrast, vanadate showed the tendency to promote adhesion-inducibl e DNA synthesis. These results suggest that DNA synthesis caused by th e cell adhesion in these cells was regulated by both phosphorylation a nd dephosphorylation at tyrosine residue. (C) 1995 Academic Press, Inc .