FIG. 3.

Analysis of SIT protein levels during synchronized cell growth. Time (h) during synchronized cell growth is shown. The top panel is a representative example of immunoblots of whole-cell protein lysates probed with anti-TpEL4. The middle panel shows net silicic acid uptake during synchronized growth based on results for triplicate samples, with errors bars for standard deviations. The bottom panel shows the mean induction (fold) based on relative densitometric units for three immunoblot analyses performed on two independent replicate cultures (see Materials and Methods). Error bars represent standard errors. Approximate timing of cellular events during synchronized growth is denoted at the bottom.