FRAGMENTATION OF FIBRONECTIN PRODUCED THE ACTIVITY STIMULATING DNA AND RNA-SYNTHESIS IN THE CELLS OF GRANULATION-TISSUE CULTURE

Human blood plasma fibronectin decreased slightly the incorporation of precursors into nucleic acids of granulation tissue culture cells. A slight fragmentation of fibronectin, where the fragments with 180-200 kD molecular mass were developed, led to occurrence of the activity 2-fold stimulating the DNA synthesis. After more effective proteolysis using plasmin and trypsin the stimulating effect of fibronectin fragments on synthesis of nucleic acids maintained and constituted 165 .+-. 12% and 127 .+-. .+-. 7% for DNA and RNA, respectively.