Changing levels of uv light and carcinogen-induced unscheduled DNA synthesis in mouse oocytes during meiotic maturation.

The effects of cytochalasin B (CB) and colchicine on the lectin-mediated agglutination of dissociated cells from chick embryos at the early primitive streak stage were studied. Cells incubated in the absence of the above-mentioned drugs were agglutinable with concanavalin A (ConA), wheat germ agglutinin (WGA), and Ricinus communis agglutinin (RCA). A pre-incubation with neuraminidase was required to render the cells agglutinable with soybean agglutinin (SBA). This treatment had no appreciable effect on the agglutinability of the cells with the other three lectins. Treatment with the drug colchicine had no appreciable effect on the extent of agglutination with any of the above-mentioned lectins. Cells treated with CB dissolved in dimethylsulfoxide (DMSO) in saline, exhibited a reduced lectin-mediated agglutinability. However, a similar decline in agglutinability was observed in controls incubated in saline containing DMSO alone. It is suggested that structures sensitive to colchicine and CB do not play a major role in the control of surface lectin receptors in early embryonic cells.