BETA-MOMORCHARIN, A PLANT GLYCOPROTEIN, INHIBITS SYNTHESIS OF MACROMOLECULES IN EMBRYOS, SPLENOCYTES AND TUMOR-CELLS

1. Beta-Momorcharin, a glycoprotein isolated from seeds of the bitter gourd, inhibited incorporation of [H-3]leucine, [H-3]uridine and [H-3]thymidine into trichloroacetic acid-precipitable radioactivity in peri-implantation mouse embryos, mouse splenocytes with or without activation by concanavalin A, and human squamous carcinoma of the tongue and larynx, but did not affect incorporation of the aforementioned radioisotopes into mouse liver cells. 2. The results suggest that inhibition of protein, RNA and DNA biosynthesis in embryos, splenocytes and tumor cells may represent the mechanism of embryotoxic, immunosuppressive and antitumor actions of beta-momorcharin. 3. The results also suggest that in mouse liver cells biosynthesis of protein, RNA and DNA was not affected by beta-momorcharin.