Figure 7.

Two-day-old seedlings of peanuts were grown in the dark at 25°C, and were transferred to 4°C and harvested after the indicated time. A, Total RNAs were isolated from the peanut seedlings and subjected to northern analysis using STY kinase full-length cDNA as a probe. For the rRNA panel, size-separated total RNA (20 μg) was stained with ethidium bromide to show that similar amounts of RNA were loaded per lane. The prominent bands are rRNAs. B, Relative mRNA levels were densitometrically estimated, and histograms were constructed with the data from Figure 7A. Error bars represent the sd of three independent experiments. C, Protein extracts (25 μg) from untreated control (0 min) or seedlings treated with cold (4°C) were subjected to immunoblot analysis with STY kinase antibodies at the indicated time periods. D, Protein extracts (250 μg) from untreated control (0 min) or seedlings treated with cold (4°C) were immunoprecipitated with 1:100 (v/v) dilution of anti-STY kinase antibodies. Kinase activity of the immune complex was subsequently determined using histone III-S as an exogenous substrate.