Figure 8.

12°C treatment of rice seedlings activates an approximately 43-kD protein kinase that preferentially uses MBP as a substrate. Seven-day-old rice seedlings were treated at 12°C or 4°C for the indicated times (hours). Untreated (25°C) seedlings were used as a control. Proteins extracted from treated or untreated shoots were separated by SDS-PAGE embedded with MBP (A) or casein (B) as a substrate. The protein kinase that is activated by 12°C treatment is indicated by an arrow in A. The size of molecular markers are shown in kilodaltons.