Investigations for the regulation of photosystem IID1:1-DNA-Interactions

In the cyanobacterium Synechococcus PCC 7942, the PSII reaction center protein D1 is encodedby a psbA gene family. Transcription of the three psbA genes is differentially regulated by light. Under highlight conditions, the transcription of psbAI is repressed and that of psbAII and psbAIII is induced. The D1:1degradation products, mediated by the protease FtsH, may be involved in transcriptionregulation of psbAI by binding in the promotor region. Additionally, C-terminal breakdown products bind to asequence with high similarity to isiB, a gene which encodes flavodoxin, a substituent for ferredoxin underiron depleted conditions in cyanobacteria