Properties of a cell growth inhibitor produced by mouse embryo fibroblasts

✍ Scribed by Valerie Wells; Livio Mallucci

• Publisher: John Wiley and Sons
• Year: 1983
• Tongue: English
• Weight: 863 KB
• Volume: 117
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1041170203

✦ Synopsis

Secondary mouse embryo fibroblasts produce a growth inhibitor with the character of a thermolabile, nondialysable protein. The inhibitor was harvested from conditioned medium, and following G-75 Sephadex fractionation it was isolated in one peak which consisted of two fractions eluting at approximately two thirds of the bed volume of the column where approximately 80 percent of the original activitywas recovered with an increase in specific activity of about tenfold. Polyacrylamide gradient gel electrophoresis of fractions from LPSI methionine-labelled conditioned medium showed that the two fractions with growth inhibitoryactivitycontained some 4-5 bands and shared the two major components. Cell cycle studies showed that the growth inhibitory effect was exerted after addition during early and late GI and during S phase, and morphological studies showed that where growth was inhibited the morphological expression of the cells was altered.

l o p Ci ml-l of L-[35S] methionine (specific activity > 600