Protein synthesis in homologous and heterologous cell-free systems from chick embryo connective tissues

Two homologous systems for cell-free protein synthesis from chick embryo connective tissues are described. Both the skin polysomes and the wing-leg polysomes are active in collagen synthesis, but they have different requirements for optimum protein synthesis. Protein synthesis was not dependent on tissue-specific factors, since heterologous preparations of supernatant enzymes or initiation factors were able to stimulate maximum protein synthesis with each fraction of polysomes.