Light‐regulated expression of the <i>psbA</i> transcript in the cyanobacterium <i>Anacystis nidulans</i>

Abstract

The level of photoinhibition as well as the rate of recovery of photosynthesis increases with increasing light intensities in Anacystis nidulans . In addition, the recovery from photoinhibition is insensitive to rifampicin. We found that the amount of psbA ‐specific mRNAs, coding for the D1 protein, was higher in cells grown in high rather than in low photon flux densities of white light. The results support the hypothesis that the rate of synthesis of the D1 protein plays a role both in the susceptibility of photosynthesis to photoinhibition and during recovery from photoinhibition. In addition, we found that a majority of the mRNAs specific for the psbA gene could be detected intact 90 min after the addition of rifampicin.