Abstract
In cyanobacteria, several genes that encode phytochrome-like protein have been identified. However their physiological functions are largely unknown. We investigated global changes in mRNA abundance in phytochrome mutants by DNA microarray analysis, which provides cue to identify physiological role of cyanobacterial phytochromes.
The following phytochrome-like genes of Synechocystis sp. PCC6803 were disrupted by insertional inactivation: sll0821, sll1124, sll1473, slr0473, slr1212, slr1393, slr1805 and slr1969. Labeled cDNA probes were synthesized from total RNA of mutant cells grown under continuous light. Transcript of cpcG gene, which encodes phycobilisome rod-core linker polypeptide, was reduced by less than 5% of the wild-type strain in sll1473 mutant. Furthermore distinct patterns of gene expression were observed in other phytochrome mutants to a lesser extent.
