PP242 inhibits the increase in protein synthesis triggered by fertilization.

<p><b>(A)</b> The rate of <i>in vivo</i> protein synthesis was monitored by the kinetics of [³⁵S]methionine incorporation into proteins. <i>S</i>. <i>granularis</i> eggs (5% cells/vol solution in FSW) were metabolically labelled in the presence of [³⁵S]methionine. After fertilization in the absence (circles) or presence (triangles) of 10 μM PP242, cytosoluble fractions were prepared from 20 μl pelleted embryos and radioactivity incorporation into TCA-precipitated proteins was determined at indicated times. Vertical bars represent Standard Error of the Mean values (SEM) obtained in 3 independent experiments <b>(B)</b> Pattern of proteins translated following fertilization of control (left panel) or PP242-treated (right) embryos. Proteins (30 μg) of the cytosoluble fractions were separated by SDS-PAGE (12%). Radioactive neo-synthetized proteins were visualized by autoradiography. Arrow shows subtle differences in the pattern of neo-synthetized proteins (see text).