Factors Controlling Protein Synthesis

摘要

The purpose of the investigation is to understand the mechanism by which enzyme synthesis is controlled in developing systems. Efforts were made to confirm the RNA induction of enzymes in Ehrlich ascites cells. Attempts to develop a system of measuring the biological activity of RNA in this respect were unsuccessful. Studies were conducted on xanthine dehydrogenase in developing chick-embryo liver. It was concluded that the appearance of this enzyme is under hormonal control. Injections of prolactin, growth hormone, luteinizing hormone, folliclestimulating hormone and thyroid-stimulating hormone, individually, or as a mixture, did not give stimulation of activity. It is further concluded that either there is a new factor in the crude extract, or that a proper balance of 2 or more hormones is required. Similar studies were also conducted on mouse Ehrlich ascites cancer cells. First, crude anterior pituitary extract produced an increase in specific activity from 2- to 5-fold. Injections of the same hormones, either individually or in a mixture approximating pituitary tissue, caused a 2- to 7-fold increase in xanthine oxidase activity with only one injection 24 hrs before harvest of ascites cells, and a 9-fold increase after a series of three injections. (Author)