Influence of light on accumulation of photosynthesis-specific transcripts in the cyanobacterium Synechocystis 6803.

Transcript accumulation for the psbA, psbD, psbD-C, rbcL-S and rrn genes in Synechocystis 6803 was followed under different light conditions. psbA, psbD, psbD-C and rbcL-S transcripts required light to accumulate and the relative abundance of these transcripts differed between high and low light conditions. Under high light conditions, steady-state levels of psbA, psbD and psbD-C transcripts were higher while levels of rbcL-S transcripts were lower than under low light conditions. rrn transcripts accumulated in the dark and the transcript levels were the same under illuminated conditions. Analyses of constructed Synechocystis 6803 mutants showed that both psbA-2 and psbA-3 could produce high levels of transcripts under illuminated conditions. No psbA-1 transcripts were detected.