Abstract
We are studying the effect of salt stress on gene expression in the filamentous cyanobacterium Anabaena sp. PCC 7120.
It was reported that an open reading flame (ORF) alr3768, named orrA, is required for the up-regulation of several genes when cells were exposed to salt stress. The OrrA contains response regulator domain of the two component regulatory system and helix-turn-helix DNA binding domain. It was speculated that OrrA functions as a transcriptional regulator for the genes responding the salt stress.
We determined the ORFs that were controlled by OrrA using Anabaena oligo nucleotide microarray. The direct binding of His-tagged OrrA to DNA was also determinded.
