Figure 5.

Northern-blot analyses of mtCA mRNA levels in synchronously grown cells. After three light/dark cycles, the culture was transferred to low CO₂ at the beginning of the fourth dark period. A, Cells left under a light/dark regime. B, Cells transferred to continuous darkness. Samples for mRNA analyses were withdrawn 1, 6, and 11 h into the light period and 1, 6, and 11.5 h into the dark period. All lanes on the northern blot contained 5 μg of total RNA.