FIG. 4.

Inhibition of protein synthesis in eIF6-depleted cells. Exponentially growing cultures of W303α or KSY603 growing in galactose medium lacking methionine (SGal-Met medium) were harvested, and approximately 10 A₂₆₀ units of cells was suspended in 150 ml of either SD-Met (glucose) or SGal-Met medium and grown at 30°C. At the indicated times, 1 A₂₆₀ unit of cells from each culture was harvested and suspended in 300 μl of either SD-Met or SGal-Met medium containing 50 μCi of [³⁵S]methionine (1175 Ci/mmol). (A) Protein synthesis rates were determined as described in Materials and Methods. The rate of protein synthesis at each time point was calculated as counts of ³⁵S radioactivity incorporated per microgram of protein per minute. (B) Each yeast strain, as indicated, were pulse-labeled for 5 min with [³⁵S]methionine in SD-Met medium, chased for 3 min with 1.5 mM nonradioactive methionine, and lysed. Similar amounts of total protein were separated by SDS-PAGE and autoradiographed.